diff options
| -rw-r--r-- | MAINTAINERS | 5 | ||||
| -rw-r--r-- | tools/Makefile | 14 | ||||
| -rw-r--r-- | tools/objtool/.gitignore | 2 | ||||
| -rw-r--r-- | tools/objtool/Build | 13 | ||||
| -rw-r--r-- | tools/objtool/Documentation/stack-validation.txt | 342 | ||||
| -rw-r--r-- | tools/objtool/Makefile | 60 | ||||
| -rw-r--r-- | tools/objtool/arch.h | 44 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/Build | 12 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/decode.c | 172 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk | 387 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/insn/inat.c | 97 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/insn/inat.h | 221 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/insn/inat_types.h | 29 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/insn/insn.c | 594 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/insn/insn.h | 201 | ||||
| -rw-r--r-- | tools/objtool/arch/x86/insn/x86-opcode-map.txt | 984 | ||||
| -rw-r--r-- | tools/objtool/builtin-check.c | 1072 | ||||
| -rw-r--r-- | tools/objtool/builtin.h | 22 | ||||
| -rw-r--r-- | tools/objtool/elf.c | 403 | ||||
| -rw-r--r-- | tools/objtool/elf.h | 79 | ||||
| -rw-r--r-- | tools/objtool/objtool.c | 136 | ||||
| -rw-r--r-- | tools/objtool/special.c | 193 | ||||
| -rw-r--r-- | tools/objtool/special.h | 42 | ||||
| -rw-r--r-- | tools/objtool/warn.h | 60 |
24 files changed, 5178 insertions, 6 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 2fa3303..545daaf 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7778,6 +7778,11 @@ L: alsa-devel@alsa-project.org (moderated for non-subscribers) S: Maintained F: sound/soc/codecs/tfa9879* +OBJTOOL +M: Josh Poimboeuf <jpoimboe@redhat.com> +S: Supported +F: tools/objtool/ + OMAP SUPPORT M: Tony Lindgren <tony@atomide.com> L: linux-omap@vger.kernel.org diff --git a/tools/Makefile b/tools/Makefile index 6339f6a..cc2a37d 100644 --- a/tools/Makefile +++ b/tools/Makefile @@ -20,6 +20,7 @@ help: @echo ' perf - Linux performance measurement and analysis tool' @echo ' selftests - various kernel selftests' @echo ' spi - spi tools' + @echo ' objtool - an ELF object analysis tool' @echo ' tmon - thermal monitoring and tuning tool' @echo ' turbostat - Intel CPU idle stats and freq reporting tool' @echo ' usb - USB testing tools' @@ -53,7 +54,7 @@ acpi: FORCE cpupower: FORCE $(call descend,power/$@) -cgroup firewire hv guest spi usb virtio vm net iio: FORCE +cgroup firewire hv guest spi usb virtio vm net iio objtool: FORCE $(call descend,$@) liblockdep: FORCE @@ -85,7 +86,7 @@ freefall: FORCE all: acpi cgroup cpupower hv firewire lguest \ perf selftests turbostat usb \ virtio vm net x86_energy_perf_policy \ - tmon freefall + tmon freefall objtool acpi_install: $(call descend,power/$(@:_install=),install) @@ -93,7 +94,7 @@ acpi_install: cpupower_install: $(call descend,power/$(@:_install=),install) -cgroup_install firewire_install hv_install lguest_install perf_install usb_install virtio_install vm_install net_install: +cgroup_install firewire_install hv_install lguest_install perf_install usb_install virtio_install vm_install net_install objtool_install: $(call descend,$(@:_install=),install) selftests_install: @@ -111,7 +112,7 @@ freefall_install: install: acpi_install cgroup_install cpupower_install hv_install firewire_install lguest_install \ perf_install selftests_install turbostat_install usb_install \ virtio_install vm_install net_install x86_energy_perf_policy_install \ - tmon_install freefall_install + tmon_install freefall_install objtool_install acpi_clean: $(call descend,power/acpi,clean) @@ -119,7 +120,7 @@ acpi_clean: cpupower_clean: $(call descend,power/cpupower,clean) -cgroup_clean hv_clean firewire_clean lguest_clean spi_clean usb_clean virtio_clean vm_clean net_clean iio_clean: +cgroup_clean hv_clean firewire_clean lguest_clean spi_clean usb_clean virtio_clean vm_clean net_clean iio_clean objtool_clean: $(call descend,$(@:_clean=),clean) liblockdep_clean: @@ -155,6 +156,7 @@ build_clean: clean: acpi_clean cgroup_clean cpupower_clean hv_clean firewire_clean lguest_clean \ perf_clean selftests_clean turbostat_clean spi_clean usb_clean virtio_clean \ vm_clean net_clean iio_clean x86_energy_perf_policy_clean tmon_clean \ - freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean + freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean \ + objtool_clean .PHONY: FORCE diff --git a/tools/objtool/.gitignore b/tools/objtool/.gitignore new file mode 100644 index 0000000..a0b3128 --- /dev/null +++ b/tools/objtool/.gitignore @@ -0,0 +1,2 @@ +arch/x86/insn/inat-tables.c +objtool diff --git a/tools/objtool/Build b/tools/objtool/Build new file mode 100644 index 0000000..0e89258 --- /dev/null +++ b/tools/objtool/Build @@ -0,0 +1,13 @@ +objtool-y += arch/$(ARCH)/ +objtool-y += builtin-check.o +objtool-y += elf.o +objtool-y += special.o +objtool-y += objtool.o + +objtool-y += libstring.o + +CFLAGS += -I$(srctree)/tools/lib + +$(OUTPUT)libstring.o: ../lib/string.c FORCE + $(call rule_mkdir) + $(call if_changed_dep,cc_o_c) diff --git a/tools/objtool/Documentation/stack-validation.txt b/tools/objtool/Documentation/stack-validation.txt new file mode 100644 index 0000000..5a95896 --- /dev/null +++ b/tools/objtool/Documentation/stack-validation.txt @@ -0,0 +1,342 @@ +Compile-time stack metadata validation +====================================== + + +Overview +-------- + +The kernel CONFIG_STACK_VALIDATION option enables a host tool named +objtool which runs at compile time. It has a "check" subcommand which +analyzes every .o file and ensures the validity of its stack metadata. +It enforces a set of rules on asm code and C inline assembly code so +that stack traces can be reliable. + +Currently it only checks frame pointer usage, but there are plans to add +CFI validation for C files and CFI generation for asm files. + +For each function, it recursively follows all possible code paths and +validates the correct frame pointer state at each instruction. + +It also follows code paths involving special sections, like +.altinstructions, __jump_table, and __ex_table, which can add +alternative execution paths to a given instruction (or set of +instructions). Similarly, it knows how to follow switch statements, for +which gcc sometimes uses jump tables. + + +Why do we need stack metadata validation? +----------------------------------------- + +Here are some of the benefits of validating stack metadata: + +a) More reliable stack traces for frame pointer enabled kernels + + Frame pointers are used for debugging purposes. They allow runtime + code and debug tools to be able to walk the stack to determine the + chain of function call sites that led to the currently executing + code. + + For some architectures, frame pointers are enabled by + CONFIG_FRAME_POINTER. For some other architectures they may be + required by the ABI (sometimes referred to as "backchain pointers"). + + For C code, gcc automatically generates instructions for setting up + frame pointers when the -fno-omit-frame-pointer option is used. + + But for asm code, the frame setup instructions have to be written by + hand, which most people don't do. So the end result is that + CONFIG_FRAME_POINTER is honored for C code but not for most asm code. + + For stack traces based on frame pointers to be reliable, all + functions which call other functions must first create a stack frame + and update the frame pointer. If a first function doesn't properly + create a stack frame before calling a second function, the *caller* + of the first function will be skipped on the stack trace. + + For example, consider the following example backtrace with frame + pointers enabled: + + [<ffffffff81812584>] dump_stack+0x4b/0x63 + [<ffffffff812d6dc2>] cmdline_proc_show+0x12/0x30 + [<ffffffff8127f568>] seq_read+0x108/0x3e0 + [<ffffffff812cce62>] proc_reg_read+0x42/0x70 + [<ffffffff81256197>] __vfs_read+0x37/0x100 + [<ffffffff81256b16>] vfs_read+0x86/0x130 + [<ffffffff81257898>] SyS_read+0x58/0xd0 + [<ffffffff8181c1f2>] entry_SYSCALL_64_fastpath+0x12/0x76 + + It correctly shows that the caller of cmdline_proc_show() is + seq_read(). + + If we remove the frame pointer logic from cmdline_proc_show() by + replacing the frame pointer related instructions with nops, here's + what it looks like instead: + + [<ffffffff81812584>] dump_stack+0x4b/0x63 + [<ffffffff812d6dc2>] cmdline_proc_show+0x12/0x30 + [<ffffffff812cce62>] proc_reg_read+0x42/0x70 + [<ffffffff81256197>] __vfs_read+0x37/0x100 + [<ffffffff81256b16>] vfs_read+0x86/0x130 + [<ffffffff81257898>] SyS_read+0x58/0xd0 + [<ffffffff8181c1f2>] entry_SYSCALL_64_fastpath+0x12/0x76 + + Notice that cmdline_proc_show()'s caller, seq_read(), has been + skipped. Instead the stack trace seems to show that + cmdline_proc_show() was called by proc_reg_read(). + + The benefit of objtool here is that because it ensures that *all* + functions honor CONFIG_FRAME_POINTER, no functions will ever[*] be + skipped on a stack trace. + + [*] unless an interrupt or exception has occurred at the very + beginning of a function before the stack frame has been created, + or at the very end of the function after the stack frame has been + destroyed. This is an inherent limitation of frame pointers. + +b) 100% reliable stack traces for DWARF enabled kernels + + (NOTE: This is not yet implemented) + + As an alternative to frame pointers, DWARF Call Frame Information + (CFI) metadata can be used to walk the stack. Unlike frame pointers, + CFI metadata is out of band. So it doesn't affect runtime + performance and it can be reliable even when interrupts or exceptions + are involved. + + For C code, gcc automatically generates DWARF CFI metadata. But for + asm code, generating CFI is a tedious manual approach which requires + manually placed .cfi assembler macros to be scattered throughout the + code. It's clumsy and very easy to get wrong, and it makes the real + code harder to read. + + Stacktool will improve this situation in several ways. For code + which already has CFI annotations, it will validate them. For code + which doesn't have CFI annotations, it will generate them. So an + architecture can opt to strip out all the manual .cfi annotations + from their asm code and have objtool generate them instead. + + We might also add a runtime stack validation debug option where we + periodically walk the stack from schedule() and/or an NMI to ensure + that the stack metadata is sane and that we reach the bottom of the + stack. + + So the benefit of objtool here will be that external tooling should + always show perfect stack traces. And the same will be true for + kernel warning/oops traces if the architecture has a runtime DWARF + unwinder. + +c) Higher live patching compatibility rate + + (NOTE: This is not yet implemented) + + Currently with CONFIG_LIVEPATCH there's a basic live patching + framework which is safe for roughly 85-90% of "security" fixes. But + patches can't have complex features like function dependency or + prototype changes, or data structure changes. + + There's a strong need to support patches which have the more complex + features so that the patch compatibility rate for security fixes can + eventually approach something resembling 100%. To achieve that, a + "consistency model" is needed, which allows tasks to be safely + transitioned from an unpatched state to a patched state. + + One of the key requirements of the currently proposed livepatch + consistency model [*] is that it needs to walk the stack of each + sleeping task to determine if it can be transitioned to the patched + state. If objtool can ensure that stack traces are reliable, this + consistency model can be used and the live patching compatibility + rate can be improved significantly. + + [*] https://lkml.kernel.org/r/cover.1423499826.git.jpoimboe@redhat.com + + +Rules +----- + +To achieve the validation, objtool enforces the following rules: + +1. Each callable function must be annotated as such with the ELF + function type. In asm code, this is typically done using the + ENTRY/ENDPROC macros. If objtool finds a return instruction + outside of a function, it flags an error since that usually indicates + callable code which should be annotated accordingly. + + This rule is needed so that objtool can properly identify each + callable function in order to analyze its stack metadata. + +2. Conversely, each section of code which is *not* callable should *not* + be annotated as an ELF function. The ENDPROC macro shouldn't be used + in this case. + + This rule is needed so that objtool can ignore non-callable code. + Such code doesn't have to follow any of the other rules. + +3. Each callable function which calls another function must have the + correct frame pointer logic, if required by CONFIG_FRAME_POINTER or + the architecture's back chain rules. This can by done in asm code + with the FRAME_BEGIN/FRAME_END macros. + + This rule ensures that frame pointer based stack traces will work as + designed. If function A doesn't create a stack frame before calling + function B, the _caller_ of function A will be skipped on the stack + trace. + +4. Dynamic jumps and jumps to undefined symbols are only allowed if: + + a) the jump is part of a switch statement; or + + b) the jump matches sibling call semantics and the frame pointer has + the same value it had on function entry. + + This rule is needed so that objtool can reliably analyze all of a + function's code paths. If a function jumps to code in another file, + and it's not a sibling call, objtool has no way to follow the jump + because it only analyzes a single file at a time. + +5. A callable function may not execute kernel entry/exit instructions. + The only code which needs such instructions is kernel entry code, + which shouldn't be be in callable functions anyway. + + This rule is just a sanity check to ensure that callable functions + return normally. + + +Errors in .S files +------------------ + +If you're getting an error in a compiled .S file which you don't +understand, first make sure that the affected code follows the above +rules. + +Here are some examples of common warnings reported by objtool, what +they mean, and suggestions for how to fix them. + + +1. asm_file.o: warning: objtool: func()+0x128: call without frame pointer save/setup + + The func() function made a function call without first saving and/or + updating the frame pointer. + + If func() is indeed a callable function, add proper frame pointer + logic using the FRAME_BEGIN and FRAME_END macros. Otherwise, remove + its ELF function annotation by changing ENDPROC to END. + + If you're getting this error in a .c file, see the "Errors in .c + files" section. + + +2. asm_file.o: warning: objtool: .text+0x53: return instruction outside of a callable function + + A return instruction was detected, but objtool couldn't find a way + for a callable function to reach the instruction. + + If the return instruction is inside (or reachable from) a callable + function, the function needs to be annotated with the ENTRY/ENDPROC + macros. + + If you _really_ need a return instruction outside of a function, and + are 100% sure that it won't affect stack traces, you can tell + objtool to ignore it. See the "Adding exceptions" section below. + + +3. asm_file.o: warning: objtool: func()+0x9: function has unreachable instruction + + The instruction lives inside of a callable function, but there's no + possible control flow path from the beginning of the function to the + instruction. + + If the instruction is actually needed, and it's actually in a + callable function, ensure that its function is properly annotated + with ENTRY/ENDPROC. + + If it's not actually in a callable function (e.g. kernel entry code), + change ENDPROC to END. + + +4. asm_file.o: warning: objtool: func(): can't find starting instruction + or + asm_file.o: warning: objtool: func()+0x11dd: can't decode instruction + + Did you put data in a text section? If so, that can confuse + objtool's instruction decoder. Move the data to a more appropriate + section like .data or .rodata. + + +5. asm_file.o: warning: objtool: func()+0x6: kernel entry/exit from callable instruction + + This is a kernel entry/exit instruction like sysenter or sysret. + Such instructions aren't allowed in a callable function, and are most + likely part of the kernel entry code. + + If the instruction isn't actually in a callable function, change + ENDPROC to END. + + +6. asm_file.o: warning: objtool: func()+0x26: sibling call from callable instruction with changed frame pointer + + This is a dynamic jump or a jump to an undefined symbol. Stacktool + assumed it's a sibling call and detected that the frame pointer + wasn't first restored to its original state. + + If it's not really a sibling call, you may need to move the + destination code to the local file. + + If the instruction is not actually in a callable function (e.g. + kernel entry code), change ENDPROC to END. + + +7. asm_file: warning: objtool: func()+0x5c: frame pointer state mismatch + + The instruction's frame pointer state is inconsistent, depending on + which execution path was taken to reach the instruction. + + Make sure the function pushes and sets up the frame pointer (for + x86_64, this means rbp) at the beginning of the function and pops it + at the end of the function. Also make sure that no other code in the + function touches the frame pointer. + + +Errors in .c files +------------------ + +If you're getting an objtool error in a compiled .c file, chances are +the file uses an asm() statement which has a "call" instruction. An +asm() statement with a call instruction must declare the use of the +stack pointer in its output operand. For example, on x86_64: + + register void *__sp asm("rsp"); + asm volatile("call func" : "+r" (__sp)); + +Otherwise the stack frame may not get created before the call. + +Another possible cause for errors in C code is if the Makefile removes +-fno-omit-frame-pointer or adds -fomit-frame-pointer to the gcc options. + +Also see the above section for .S file errors for more information what +the individual error messages mean. + +If the error doesn't seem to make sense, it could be a bug in objtool. +Feel free to ask the objtool maintainer for help. + + +Adding exceptions +----------------- + +If you _really_ need objtool to ignore something, and are 100% sure +that it won't affect kernel stack traces, you can tell objtool to +ignore it: + +- To skip validation of a function, use the STACK_FRAME_NON_STANDARD + macro. + +- To skip validation of a file, add + + OBJECT_FILES_NON_STANDARD_filename.o := n + + to the Makefile. + +- To skip validation of a directory, add + + OBJECT_FILES_NON_STANDARD := y + + to the Makefile. diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile new file mode 100644 index 0000000..c4f0713 --- /dev/null +++ b/tools/objtool/Makefile @@ -0,0 +1,60 @@ +include ../scripts/Makefile.include + +ifndef ($(ARCH)) +ARCH ?= $(shell uname -m) +ifeq ($(ARCH),x86_64) +ARCH := x86 +endif +endif + +ifeq ($(srctree),) +srctree := $(patsubst %/,%,$(dir $(shell pwd))) +srctree := $(patsubst %/,%,$(dir $(srctree))) +endif + +SUBCMD_SRCDIR = $(srctree)/tools/lib/subcmd/ +LIBSUBCMD = $(if $(OUTPUT),$(OUTPUT),$(SUBCMD_SRCDIR))libsubcmd.a + +OBJTOOL := $(OUTPUT)objtool +OBJTOOL_IN := $(OBJTOOL)-in.o + +all: $(OBJTOOL) + +INCLUDES := -I$(srctree)/tools/include +CFLAGS += -Wall -Werror $(EXTRA_WARNINGS) -fomit-frame-pointer -O2 $(INCLUDES) +LDFLAGS += -lelf $(LIBSUBCMD) + +AWK = awk +export srctree OUTPUT CFLAGS ARCH AWK +include $(srctree)/tools/build/Makefile.include + +$(OBJTOOL_IN): fixdep FORCE + @$(MAKE) $(build)=objtool + +$(OBJTOOL): $(LIBSUBCMD) $(OBJTOOL_IN) + @(test -d ../../kernel -a -d ../../tools -a -d ../objtool && (( \ + diff -I'^#include' arch/x86/insn/insn.c ../../arch/x86/lib/insn.c >/dev/null && \ + diff -I'^#include' arch/x86/insn/inat.c ../../arch/x86/lib/inat.c >/dev/null && \ + diff arch/x86/insn/x86-opcode-map.txt ../../arch/x86/lib/x86-opcode-map.txt >/dev/null && \ + diff arch/x86/insn/gen-insn-attr-x86.awk ../../arch/x86/tools/gen-insn-attr-x86.awk >/dev/null && \ + diff -I'^#include' arch/x86/insn/insn.h ../../arch/x86/include/asm/insn.h >/dev/null && \ + diff -I'^#include' arch/x86/insn/inat.h ../../arch/x86/include/asm/inat.h >/dev/null && \ + diff -I'^#include' arch/x86/insn/inat_types.h ../../arch/x86/include/asm/inat_types.h >/dev/null) \ + || echo "Warning: objtool: x86 instruction decoder differs from kernel" >&2 )) || true + $(QUIET_LINK)$(CC) $(OBJTOOL_IN) $(LDFLAGS) -o $@ + + +$(LIBSUBCMD): fixdep FORCE + $(Q)$(MAKE) -C $(SUBCMD_SRCDIR) + +$(LIBSUBCMD)-clean: + $(Q)$(MAKE) -C $(SUBCMD_SRCDIR) clean > /dev/null + +clean: $(LIBSUBCMD)-clean + $(call QUIET_CLEAN, objtool) $(RM) $(OBJTOOL) + $(Q)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete + $(Q)$(RM) $(OUTPUT)arch/x86/insn/inat-tables.c $(OUTPUT)fixdep + +FORCE: + +.PHONY: clean FORCE diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h new file mode 100644 index 0000000..f7350fc --- /dev/null +++ b/tools/objtool/arch.h @@ -0,0 +1,44 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef _ARCH_H +#define _ARCH_H + +#include <stdbool.h> +#include "elf.h" + +#define INSN_FP_SAVE 1 +#define INSN_FP_SETUP 2 +#define INSN_FP_RESTORE 3 +#define INSN_JUMP_CONDITIONAL 4 +#define INSN_JUMP_UNCONDITIONAL 5 +#define INSN_JUMP_DYNAMIC 6 +#define INSN_CALL 7 +#define INSN_CALL_DYNAMIC 8 +#define INSN_RETURN 9 +#define INSN_CONTEXT_SWITCH 10 +#define INSN_BUG 11 +#define INSN_NOP 12 +#define INSN_OTHER 13 +#define INSN_LAST INSN_OTHER + +int arch_decode_instruction(struct elf *elf, struct section *sec, + unsigned long offset, unsigned int maxlen, + unsigned int *len, unsigned char *type, + unsigned long *displacement); + +#endif /* _ARCH_H */ diff --git a/tools/objtool/arch/x86/Build b/tools/objtool/arch/x86/Build new file mode 100644 index 0000000..debbdb0 --- /dev/null +++ b/tools/objtool/arch/x86/Build @@ -0,0 +1,12 @@ +objtool-y += decode.o + +inat_tables_script = arch/x86/insn/gen-insn-attr-x86.awk +inat_tables_maps = arch/x86/insn/x86-opcode-map.txt + +$(OUTPUT)arch/x86/insn/inat-tables.c: $(inat_tables_script) $(inat_tables_maps) + $(call rule_mkdir) + $(Q)$(call echo-cmd,gen)$(AWK) -f $(inat_tables_script) $(inat_tables_maps) > $@ + +$(OUTPUT)arch/x86/decode.o: $(OUTPUT)arch/x86/insn/inat-tables.c + +CFLAGS_decode.o += -I$(OUTPUT)arch/x86/insn diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c new file mode 100644 index 0000000..c0c0b26 --- /dev/null +++ b/tools/objtool/arch/x86/decode.c @@ -0,0 +1,172 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include <stdio.h> +#include <stdlib.h> + +#define unlikely(cond) (cond) +#include "insn/insn.h" +#include "insn/inat.c" +#include "insn/insn.c" + +#include "../../elf.h" +#include "../../arch.h" +#include "../../warn.h" + +static int is_x86_64(struct elf *elf) +{ + switch (elf->ehdr.e_machine) { + case EM_X86_64: + return 1; + case EM_386: + return 0; + default: + WARN("unexpected ELF machine type %d", elf->ehdr.e_machine); + return -1; + } +} + +int arch_decode_instruction(struct elf *elf, struct section *sec, + unsigned long offset, unsigned int maxlen, + unsigned int *len, unsigned char *type, + unsigned long *immediate) +{ + struct insn insn; + int x86_64; + unsigned char op1, op2, ext; + + x86_64 = is_x86_64(elf); + if (x86_64 == -1) + return -1; + + insn_init(&insn, (void *)(sec->data + offset), maxlen, x86_64); + insn_get_length(&insn); + insn_get_opcode(&insn); + insn_get_modrm(&insn); + insn_get_immediate(&insn); + + if (!insn_complete(&insn)) { + WARN_FUNC("can't decode instruction", sec, offset); + return -1; + } + + *len = insn.length; + *type = INSN_OTHER; + + if (insn.vex_prefix.nbytes) + return 0; + + op1 = insn.opcode.bytes[0]; + op2 = insn.opcode.bytes[1]; + + switch (op1) { + case 0x55: + if (!insn.rex_prefix.nbytes) + /* push rbp */ + *type = INSN_FP_SAVE; + break; + + case 0x5d: + if (!insn.rex_prefix.nbytes) + /* pop rbp */ + *type = INSN_FP_RESTORE; + break; + + case 0x70 ... 0x7f: + *type = INSN_JUMP_CONDITIONAL; + break; + + case 0x89: + if (insn.rex_prefix.nbytes == 1 && + insn.rex_prefix.bytes[0] == 0x48 && + insn.modrm.nbytes && insn.modrm.bytes[0] == 0xe5) + /* mov rsp, rbp */ + *type = INSN_FP_SETUP; + break; + + case 0x90: + *type = INSN_NOP; + break; + + case 0x0f: + if (op2 >= 0x80 && op2 <= 0x8f) + *type = INSN_JUMP_CONDITIONAL; + else if (op2 == 0x05 || op2 == 0x07 || op2 == 0x34 || + op2 == 0x35) + /* sysenter, sysret */ + *type = INSN_CONTEXT_SWITCH; + else if (op2 == 0x0b || op2 == 0xb9) + /* ud2 */ + *type = INSN_BUG; + else if (op2 == 0x0d || op2 == 0x1f) + /* nopl/nopw */ + *type = INSN_NOP; + else if (op2 == 0x01 && insn.modrm.nbytes && + (insn.modrm.bytes[0] == 0xc2 || + insn.modrm.bytes[0] == 0xd8)) + /* vmlaunch, vmrun */ + *type = INSN_CONTEXT_SWITCH; + + break; + + case 0xc9: /* leave */ + *type = INSN_FP_RESTORE; + break; + + case 0xe3: /* jecxz/jrcxz */ + *type = INSN_JUMP_CONDITIONAL; + break; + + case 0xe9: + case 0xeb: + *type = INSN_JUMP_UNCONDITIONAL; + break; + + case 0xc2: + case 0xc3: + *type = INSN_RETURN; + break; + + case 0xc5: /* iret */ + case 0xca: /* retf */ + case 0xcb: /* retf */ + *type = INSN_CONTEXT_SWITCH; + break; + + case 0xe8: + *type = INSN_CALL; + break; + + case 0xff: + ext = X86_MODRM_REG(insn.modrm.bytes[0]); + if (ext == 2 || ext == 3) + *type = INSN_CALL_DYNAMIC; + else if (ext == 4) + *type = INSN_JUMP_DYNAMIC; + else if (ext == 5) /*jmpf */ + *type = INSN_CONTEXT_SWITCH; + + break; + + default: + break; + } + + *immediate = insn.immediate.nbytes ? insn.immediate.value : 0; + + return 0; +} diff --git a/tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk b/tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk new file mode 100644 index 0000000..093a892 --- /dev/null +++ b/tools/objtool/arch/x86/insn/gen-insn-attr-x86.awk @@ -0,0 +1,387 @@ +#!/bin/awk -f +# gen-insn-attr-x86.awk: Instruction attribute table generator +# Written by Masami Hiramatsu <mhiramat@redhat.com> +# +# Usage: awk -f gen-insn-attr-x86.awk x86-opcode-map.txt > inat-tables.c + +# Awk implementation sanity check +function check_awk_implement() { + if (sprintf("%x", 0) != "0") + return "Your awk has a printf-format problem." + return "" +} + +# Clear working vars +function clear_vars() { + delete table + delete lptable2 + delete lptable1 + delete lptable3 + eid = -1 # escape id + gid = -1 # group id + aid = -1 # AVX id + tname = "" +} + +BEGIN { + # Implementation error checking + awkchecked = check_awk_implement() + if (awkchecked != "") { + print "Error: " awkchecked > "/dev/stderr" + print "Please try to use gawk." > "/dev/stderr" + exit 1 + } + + # Setup generating tables + print "/* x86 opcode map generated from x86-opcode-map.txt */" + print "/* Do not change this code. */\n" + ggid = 1 + geid = 1 + gaid = 0 + delete etable + delete gtable + delete atable + + opnd_expr = "^[A-Za-z/]" + ext_expr = "^\\(" + sep_expr = "^\\|$" + group_expr = "^Grp[0-9A-Za-z]+" + + imm_expr = "^[IJAOL][a-z]" + imm_flag["Ib"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)" + imm_flag["Jb"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)" + imm_flag["Iw"] = "INAT_MAKE_IMM(INAT_IMM_WORD)" + imm_flag["Id"] = "INAT_MAKE_IMM(INAT_IMM_DWORD)" + imm_flag["Iq"] = "INAT_MAKE_IMM(INAT_IMM_QWORD)" + imm_flag["Ap"] = "INAT_MAKE_IMM(INAT_IMM_PTR)" + imm_flag["Iz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)" + imm_flag["Jz"] = "INAT_MAKE_IMM(INAT_IMM_VWORD32)" + imm_flag["Iv"] = "INAT_MAKE_IMM(INAT_IMM_VWORD)" + imm_flag["Ob"] = "INAT_MOFFSET" + imm_flag["Ov"] = "INAT_MOFFSET" + imm_flag["Lx"] = "INAT_MAKE_IMM(INAT_IMM_BYTE)" + + modrm_expr = "^([CDEGMNPQRSUVW/][a-z]+|NTA|T[012])" + force64_expr = "\\([df]64\\)" + rex_expr = "^REX(\\.[XRWB]+)*" + fpu_expr = "^ESC" # TODO + + lprefix1_expr = "\\((66|!F3)\\)" + lprefix2_expr = "\\(F3\\)" + lprefix3_expr = "\\((F2|!F3|66\\&F2)\\)" + lprefix_expr = "\\((66|F2|F3)\\)" + max_lprefix = 4 + + # All opcodes starting with lower-case 'v' or with (v1) superscript + # accepts VEX prefix + vexok_opcode_expr = "^v.*" + vexok_expr = "\\(v1\\)" + # All opcodes with (v) superscript supports *only* VEX prefix + vexonly_expr = "\\(v\\)" + + prefix_expr = "\\(Prefix\\)" + prefix_num["Operand-Size"] = "INAT_PFX_OPNDSZ" + prefix_num["REPNE"] = "INAT_PFX_REPNE" + prefix_num["REP/REPE"] = "INAT_PFX_REPE" + prefix_num["XACQUIRE"] = "INAT_PFX_REPNE" + prefix_num["XRELEASE"] = "INAT_PFX_REPE" + prefix_num["LOCK"] = "INAT_PFX_LOCK" + prefix_num["SEG=CS"] = "INAT_PFX_CS" + prefix_num["SEG=DS"] = "INAT_PFX_DS" + prefix_num["SEG=ES"] = "INAT_PFX_ES" + prefix_num["SEG=FS"] = "INAT_PFX_FS" + prefix_num["SEG=GS"] = "INAT_PFX_GS" + prefix_num["SEG=SS"] = "INAT_PFX_SS" + prefix_num["Address-Size"] = "INAT_PFX_ADDRSZ" + prefix_num["VEX+1byte"] = "INAT_PFX_VEX2" + prefix_num["VEX+2byte"] = "INAT_PFX_VEX3" + + clear_vars() +} + +function semantic_error(msg) { + print "Semantic error at " NR ": " msg > "/dev/stderr" + exit 1 +} + +function debug(msg) { + print "DEBUG: " msg +} + +function array_size(arr, i,c) { + c = 0 + for (i in arr) + c++ + return c +} + +/^Table:/ { + print "/* " $0 " */" + if (tname != "") + semantic_error("Hit Table: before EndTable:."); +} + +/^Referrer:/ { + if (NF != 1) { + # escape opcode table + ref = "" + for (i = 2; i <= NF; i++) + ref = ref $i + eid = escape[ref] + tname = sprintf("inat_escape_table_%d", eid) + } +} + +/^AVXcode:/ { + if (NF != 1) { + # AVX/escape opcode table + aid = $2 + if (gaid <= aid) + gaid = aid + 1 + if (tname == "") # AVX only opcode table + tname = sprintf("inat_avx_table_%d", $2) + } + if (aid == -1 && eid == -1) # primary opcode table + tname = "inat_primary_table" +} + +/^GrpTable:/ { + print "/* " $0 " */" + if (!($2 in group)) + semantic_error("No group: " $2 ) + gid = group[$2] + tname = "inat_group_table_" gid +} + +function print_table(tbl,name,fmt,n) +{ + print "const insn_attr_t " name " = {" + for (i = 0; i < n; i++) { + id = sprintf(fmt, i) + if (tbl[id]) + print " [" id "] = " tbl[id] "," + } + print "};" +} + +/^EndTable/ { + if (gid != -1) { + # print group tables + if (array_size(table) != 0) { + print_table(table, tname "[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,0] = tname + } + if (array_size(lptable1) != 0) { + print_table(lptable1, tname "_1[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,1] = tname "_1" + } + if (array_size(lptable2) != 0) { + print_table(lptable2, tname "_2[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,2] = tname "_2" + } + if (array_size(lptable3) != 0) { + print_table(lptable3, tname "_3[INAT_GROUP_TABLE_SIZE]", + "0x%x", 8) + gtable[gid,3] = tname "_3" + } + } else { + # print primary/escaped tables + if (array_size(table) != 0) { + print_table(table, tname "[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,0] = tname + if (aid >= 0) + atable[aid,0] = tname + } + if (array_size(lptable1) != 0) { + print_table(lptable1,tname "_1[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,1] = tname "_1" + if (aid >= 0) + atable[aid,1] = tname "_1" + } + if (array_size(lptable2) != 0) { + print_table(lptable2,tname "_2[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,2] = tname "_2" + if (aid >= 0) + atable[aid,2] = tname "_2" + } + if (array_size(lptable3) != 0) { + print_table(lptable3,tname "_3[INAT_OPCODE_TABLE_SIZE]", + "0x%02x", 256) + etable[eid,3] = tname "_3" + if (aid >= 0) + atable[aid,3] = tname "_3" + } + } + print "" + clear_vars() +} + +function add_flags(old,new) { + if (old && new) + return old " | " new + else if (old) + return old + else + return new +} + +# convert operands to flags. +function convert_operands(count,opnd, i,j,imm,mod) +{ + imm = null + mod = null + for (j = 1; j <= count; j++) { + i = opnd[j] + if (match(i, imm_expr) == 1) { + if (!imm_flag[i]) + semantic_error("Unknown imm opnd: " i) + if (imm) { + if (i != "Ib") + semantic_error("Second IMM error") + imm = add_flags(imm, "INAT_SCNDIMM") + } else + imm = imm_flag[i] + } else if (match(i, modrm_expr)) + mod = "INAT_MODRM" + } + return add_flags(imm, mod) +} + +/^[0-9a-f]+\:/ { + if (NR == 1) + next + # get index + idx = "0x" substr($1, 1, index($1,":") - 1) + if (idx in table) + semantic_error("Redefine " idx " in " tname) + + # check if escaped opcode + if ("escape" == $2) { + if ($3 != "#") + semantic_error("No escaped name") + ref = "" + for (i = 4; i <= NF; i++) + ref = ref $i + if (ref in escape) + semantic_error("Redefine escape (" ref ")") + escape[ref] = geid + geid++ + table[idx] = "INAT_MAKE_ESCAPE(" escape[ref] ")" + next + } + + variant = null + # converts + i = 2 + while (i <= NF) { + opcode = $(i++) + delete opnds + ext = null + flags = null + opnd = null + # parse one opcode + if (match($i, opnd_expr)) { + opnd = $i + count = split($(i++), opnds, ",") + flags = convert_operands(count, opnds) + } + if (match($i, ext_expr)) + ext = $(i++) + if (match($i, sep_expr)) + i++ + else if (i < NF) + semantic_error($i " is not a separator") + + # check if group opcode + if (match(opcode, group_expr)) { + if (!(opcode in group)) { + group[opcode] = ggid + ggid++ + } + flags = add_flags(flags, "INAT_MAKE_GROUP(" group[opcode] ")") + } + # check force(or default) 64bit + if (match(ext, force64_expr)) + flags = add_flags(flags, "INAT_FORCE64") + + # check REX prefix + if (match(opcode, rex_expr)) + flags = add_flags(flags, "INAT_MAKE_PREFIX(INAT_PFX_REX)") + + # check coprocessor escape : TODO + if (match(opcode, fpu_expr)) + flags = add_flags(flags, "INAT_MODRM") + + # check VEX codes + if (match(ext, vexonly_expr)) + flags = add_flags(flags, "INAT_VEXOK | INAT_VEXONLY") + else if (match(ext, vexok_expr) || match(opcode, vexok_opcode_expr)) + flags = add_flags(flags, "INAT_VEXOK") + + # check prefixes + if (match(ext, prefix_expr)) { + if (!prefix_num[opcode]) + semantic_error("Unknown prefix: " opcode) + flags = add_flags(flags, "INAT_MAKE_PREFIX(" prefix_num[opcode] ")") + } + if (length(flags) == 0) + continue + # check if last prefix + if (match(ext, lprefix1_expr)) { + lptable1[idx] = add_flags(lptable1[idx],flags) + variant = "INAT_VARIANT" + } + if (match(ext, lprefix2_expr)) { + lptable2[idx] = add_flags(lptable2[idx],flags) + variant = "INAT_VARIANT" + } + if (match(ext, lprefix3_expr)) { + lptable3[idx] = add_flags(lptable3[idx],flags) + variant = "INAT_VARIANT" + } + if (!match(ext, lprefix_expr)){ + table[idx] = add_flags(table[idx],flags) + } + } + if (variant) + table[idx] = add_flags(table[idx],variant) +} + +END { + if (awkchecked != "") + exit 1 + # print escape opcode map's array + print "/* Escape opcode map array */" + print "const insn_attr_t * const inat_escape_tables[INAT_ESC_MAX + 1]" \ + "[INAT_LSTPFX_MAX + 1] = {" + for (i = 0; i < geid; i++) + for (j = 0; j < max_lprefix; j++) + if (etable[i,j]) + print " ["i"]["j"] = "etable[i,j]"," + print "};\n" + # print group opcode map's array + print "/* Group opcode map array */" + print "const insn_attr_t * const inat_group_tables[INAT_GRP_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1] = {" + for (i = 0; i < ggid; i++) + for (j = 0; j < max_lprefix; j++) + if (gtable[i,j]) + print " ["i"]["j"] = "gtable[i,j]"," + print "};\n" + # print AVX opcode map's array + print "/* AVX opcode map array */" + print "const insn_attr_t * const inat_avx_tables[X86_VEX_M_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1] = {" + for (i = 0; i < gaid; i++) + for (j = 0; j < max_lprefix; j++) + if (atable[i,j]) + print " ["i"]["j"] = "atable[i,j]"," + print "};" +} + diff --git a/tools/objtool/arch/x86/insn/inat.c b/tools/objtool/arch/x86/insn/inat.c new file mode 100644 index 0000000..e4bf28e --- /dev/null +++ b/tools/objtool/arch/x86/insn/inat.c @@ -0,0 +1,97 @@ +/* + * x86 instruction attribute tables + * + * Written by Masami Hiramatsu <mhiramat@redhat.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ +#include "insn.h" + +/* Attribute tables are generated from opcode map */ +#include "inat-tables.c" + +/* Attribute search APIs */ +insn_attr_t inat_get_opcode_attribute(insn_byte_t opcode) +{ + return inat_primary_table[opcode]; +} + +int inat_get_last_prefix_id(insn_byte_t last_pfx) +{ + insn_attr_t lpfx_attr; + + lpfx_attr = inat_get_opcode_attribute(last_pfx); + return inat_last_prefix_id(lpfx_attr); +} + +insn_attr_t inat_get_escape_attribute(insn_byte_t opcode, int lpfx_id, + insn_attr_t esc_attr) +{ + const insn_attr_t *table; + int n; + + n = inat_escape_id(esc_attr); + + table = inat_escape_tables[n][0]; + if (!table) + return 0; + if (inat_has_variant(table[opcode]) && lpfx_id) { + table = inat_escape_tables[n][lpfx_id]; + if (!table) + return 0; + } + return table[opcode]; +} + +insn_attr_t inat_get_group_attribute(insn_byte_t modrm, int lpfx_id, + insn_attr_t grp_attr) +{ + const insn_attr_t *table; + int n; + + n = inat_group_id(grp_attr); + + table = inat_group_tables[n][0]; + if (!table) + return inat_group_common_attribute(grp_attr); + if (inat_has_variant(table[X86_MODRM_REG(modrm)]) && lpfx_id) { + table = inat_group_tables[n][lpfx_id]; + if (!table) + return inat_group_common_attribute(grp_attr); + } + return table[X86_MODRM_REG(modrm)] | + inat_group_common_attribute(grp_attr); +} + +insn_attr_t inat_get_avx_attribute(insn_byte_t opcode, insn_byte_t vex_m, + insn_byte_t vex_p) +{ + const insn_attr_t *table; + if (vex_m > X86_VEX_M_MAX || vex_p > INAT_LSTPFX_MAX) + return 0; + /* At first, this checks the master table */ + table = inat_avx_tables[vex_m][0]; + if (!table) + return 0; + if (!inat_is_group(table[opcode]) && vex_p) { + /* If this is not a group, get attribute directly */ + table = inat_avx_tables[vex_m][vex_p]; + if (!table) + return 0; + } + return table[opcode]; +} + diff --git a/tools/objtool/arch/x86/insn/inat.h b/tools/objtool/arch/x86/insn/inat.h new file mode 100644 index 0000000..611645e --- /dev/null +++ b/tools/objtool/arch/x86/insn/inat.h @@ -0,0 +1,221 @@ +#ifndef _ASM_X86_INAT_H +#define _ASM_X86_INAT_H +/* + * x86 instruction attributes + * + * Written by Masami Hiramatsu <mhiramat@redhat.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ +#include "inat_types.h" + +/* + * Internal bits. Don't use bitmasks directly, because these bits are + * unstable. You should use checking functions. + */ + +#define INAT_OPCODE_TABLE_SIZE 256 +#define INAT_GROUP_TABLE_SIZE 8 + +/* Legacy last prefixes */ +#define INAT_PFX_OPNDSZ 1 /* 0x66 */ /* LPFX1 */ +#define INAT_PFX_REPE 2 /* 0xF3 */ /* LPFX2 */ +#define INAT_PFX_REPNE 3 /* 0xF2 */ /* LPFX3 */ +/* Other Legacy prefixes */ +#define INAT_PFX_LOCK 4 /* 0xF0 */ +#define INAT_PFX_CS 5 /* 0x2E */ +#define INAT_PFX_DS 6 /* 0x3E */ +#define INAT_PFX_ES 7 /* 0x26 */ +#define INAT_PFX_FS 8 /* 0x64 */ +#define INAT_PFX_GS 9 /* 0x65 */ +#define INAT_PFX_SS 10 /* 0x36 */ +#define INAT_PFX_ADDRSZ 11 /* 0x67 */ +/* x86-64 REX prefix */ +#define INAT_PFX_REX 12 /* 0x4X */ +/* AVX VEX prefixes */ +#define INAT_PFX_VEX2 13 /* 2-bytes VEX prefix */ +#define INAT_PFX_VEX3 14 /* 3-bytes VEX prefix */ + +#define INAT_LSTPFX_MAX 3 +#define INAT_LGCPFX_MAX 11 + +/* Immediate size */ +#define INAT_IMM_BYTE 1 +#define INAT_IMM_WORD 2 +#define INAT_IMM_DWORD 3 +#define INAT_IMM_QWORD 4 +#define INAT_IMM_PTR 5 +#define INAT_IMM_VWORD32 6 +#define INAT_IMM_VWORD 7 + +/* Legacy prefix */ +#define INAT_PFX_OFFS 0 +#define INAT_PFX_BITS 4 +#define INAT_PFX_MAX ((1 << INAT_PFX_BITS) - 1) +#define INAT_PFX_MASK (INAT_PFX_MAX << INAT_PFX_OFFS) +/* Escape opcodes */ +#define INAT_ESC_OFFS (INAT_PFX_OFFS + INAT_PFX_BITS) +#define INAT_ESC_BITS 2 +#define INAT_ESC_MAX ((1 << INAT_ESC_BITS) - 1) +#define INAT_ESC_MASK (INAT_ESC_MAX << INAT_ESC_OFFS) +/* Group opcodes (1-16) */ +#define INAT_GRP_OFFS (INAT_ESC_OFFS + INAT_ESC_BITS) +#define INAT_GRP_BITS 5 +#define INAT_GRP_MAX ((1 << INAT_GRP_BITS) - 1) +#define INAT_GRP_MASK (INAT_GRP_MAX << INAT_GRP_OFFS) +/* Immediates */ +#define INAT_IMM_OFFS (INAT_GRP_OFFS + INAT_GRP_BITS) +#define INAT_IMM_BITS 3 +#define INAT_IMM_MASK (((1 << INAT_IMM_BITS) - 1) << INAT_IMM_OFFS) +/* Flags */ +#define INAT_FLAG_OFFS (INAT_IMM_OFFS + INAT_IMM_BITS) +#define INAT_MODRM (1 << (INAT_FLAG_OFFS)) +#define INAT_FORCE64 (1 << (INAT_FLAG_OFFS + 1)) +#define INAT_SCNDIMM (1 << (INAT_FLAG_OFFS + 2)) +#define INAT_MOFFSET (1 << (INAT_FLAG_OFFS + 3)) +#define INAT_VARIANT (1 << (INAT_FLAG_OFFS + 4)) +#define INAT_VEXOK (1 << (INAT_FLAG_OFFS + 5)) +#define INAT_VEXONLY (1 << (INAT_FLAG_OFFS + 6)) +/* Attribute making macros for attribute tables */ +#define INAT_MAKE_PREFIX(pfx) (pfx << INAT_PFX_OFFS) +#define INAT_MAKE_ESCAPE(esc) (esc << INAT_ESC_OFFS) +#define INAT_MAKE_GROUP(grp) ((grp << INAT_GRP_OFFS) | INAT_MODRM) +#define INAT_MAKE_IMM(imm) (imm << INAT_IMM_OFFS) + +/* Attribute search APIs */ +extern insn_attr_t inat_get_opcode_attribute(insn_byte_t opcode); +extern int inat_get_last_prefix_id(insn_byte_t last_pfx); +extern insn_attr_t inat_get_escape_attribute(insn_byte_t opcode, + int lpfx_id, + insn_attr_t esc_attr); +extern insn_attr_t inat_get_group_attribute(insn_byte_t modrm, + int lpfx_id, + insn_attr_t esc_attr); +extern insn_attr_t inat_get_avx_attribute(insn_byte_t opcode, + insn_byte_t vex_m, + insn_byte_t vex_pp); + +/* Attribute checking functions */ +static inline int inat_is_legacy_prefix(insn_attr_t attr) +{ + attr &= INAT_PFX_MASK; + return attr && attr <= INAT_LGCPFX_MAX; +} + +static inline int inat_is_address_size_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_ADDRSZ; +} + +static inline int inat_is_operand_size_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_OPNDSZ; +} + +static inline int inat_is_rex_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_REX; +} + +static inline int inat_last_prefix_id(insn_attr_t attr) +{ + if ((attr & INAT_PFX_MASK) > INAT_LSTPFX_MAX) + return 0; + else + return attr & INAT_PFX_MASK; +} + +static inline int inat_is_vex_prefix(insn_attr_t attr) +{ + attr &= INAT_PFX_MASK; + return attr == INAT_PFX_VEX2 || attr == INAT_PFX_VEX3; +} + +static inline int inat_is_vex3_prefix(insn_attr_t attr) +{ + return (attr & INAT_PFX_MASK) == INAT_PFX_VEX3; +} + +static inline int inat_is_escape(insn_attr_t attr) +{ + return attr & INAT_ESC_MASK; +} + +static inline int inat_escape_id(insn_attr_t attr) +{ + return (attr & INAT_ESC_MASK) >> INAT_ESC_OFFS; +} + +static inline int inat_is_group(insn_attr_t attr) +{ + return attr & INAT_GRP_MASK; +} + +static inline int inat_group_id(insn_attr_t attr) +{ + return (attr & INAT_GRP_MASK) >> INAT_GRP_OFFS; +} + +static inline int inat_group_common_attribute(insn_attr_t attr) +{ + return attr & ~INAT_GRP_MASK; +} + +static inline int inat_has_immediate(insn_attr_t attr) +{ + return attr & INAT_IMM_MASK; +} + +static inline int inat_immediate_size(insn_attr_t attr) +{ + return (attr & INAT_IMM_MASK) >> INAT_IMM_OFFS; +} + +static inline int inat_has_modrm(insn_attr_t attr) +{ + return attr & INAT_MODRM; +} + +static inline int inat_is_force64(insn_attr_t attr) +{ + return attr & INAT_FORCE64; +} + +static inline int inat_has_second_immediate(insn_attr_t attr) +{ + return attr & INAT_SCNDIMM; +} + +static inline int inat_has_moffset(insn_attr_t attr) +{ + return attr & INAT_MOFFSET; +} + +static inline int inat_has_variant(insn_attr_t attr) +{ + return attr & INAT_VARIANT; +} + +static inline int inat_accept_vex(insn_attr_t attr) +{ + return attr & INAT_VEXOK; +} + +static inline int inat_must_vex(insn_attr_t attr) +{ + return attr & INAT_VEXONLY; +} +#endif diff --git a/tools/objtool/arch/x86/insn/inat_types.h b/tools/objtool/arch/x86/insn/inat_types.h new file mode 100644 index 0000000..cb3c20c --- /dev/null +++ b/tools/objtool/arch/x86/insn/inat_types.h @@ -0,0 +1,29 @@ +#ifndef _ASM_X86_INAT_TYPES_H +#define _ASM_X86_INAT_TYPES_H +/* + * x86 instruction attributes + * + * Written by Masami Hiramatsu <mhiramat@redhat.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ + +/* Instruction attributes */ +typedef unsigned int insn_attr_t; +typedef unsigned char insn_byte_t; +typedef signed int insn_value_t; + +#endif diff --git a/tools/objtool/arch/x86/insn/insn.c b/tools/objtool/arch/x86/insn/insn.c new file mode 100644 index 0000000..47314a6 --- /dev/null +++ b/tools/objtool/arch/x86/insn/insn.c @@ -0,0 +1,594 @@ +/* + * x86 instruction analysis + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2002, 2004, 2009 + */ + +#ifdef __KERNEL__ +#include <linux/string.h> +#else +#include <string.h> +#endif +#include "inat.h" +#include "insn.h" + +/* Verify next sizeof(t) bytes can be on the same instruction */ +#define validate_next(t, insn, n) \ + ((insn)->next_byte + sizeof(t) + n <= (insn)->end_kaddr) + +#define __get_next(t, insn) \ + ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; }) + +#define __peek_nbyte_next(t, insn, n) \ + ({ t r = *(t*)((insn)->next_byte + n); r; }) + +#define get_next(t, insn) \ + ({ if (unlikely(!validate_next(t, insn, 0))) goto err_out; __get_next(t, insn); }) + +#define peek_nbyte_next(t, insn, n) \ + ({ if (unlikely(!validate_next(t, insn, n))) goto err_out; __peek_nbyte_next(t, insn, n); }) + +#define peek_next(t, insn) peek_nbyte_next(t, insn, 0) + +/** + * insn_init() - initialize struct insn + * @insn: &struct insn to be initialized + * @kaddr: address (in kernel memory) of instruction (or copy thereof) + * @x86_64: !0 for 64-bit kernel or 64-bit app + */ +void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64) +{ + /* + * Instructions longer than MAX_INSN_SIZE (15 bytes) are invalid + * even if the input buffer is long enough to hold them. + */ + if (buf_len > MAX_INSN_SIZE) + buf_len = MAX_INSN_SIZE; + + memset(insn, 0, sizeof(*insn)); + insn->kaddr = kaddr; + insn->end_kaddr = kaddr + buf_len; + insn->next_byte = kaddr; + insn->x86_64 = x86_64 ? 1 : 0; + insn->opnd_bytes = 4; + if (x86_64) + insn->addr_bytes = 8; + else + insn->addr_bytes = 4; +} + +/** + * insn_get_prefixes - scan x86 instruction prefix bytes + * @insn: &struct insn containing instruction + * + * Populates the @insn->prefixes bitmap, and updates @insn->next_byte + * to point to the (first) opcode. No effect if @insn->prefixes.got + * is already set. + */ +void insn_get_prefixes(struct insn *insn) +{ + struct insn_field *prefixes = &insn->prefixes; + insn_attr_t attr; + insn_byte_t b, lb; + int i, nb; + + if (prefixes->got) + return; + + nb = 0; + lb = 0; + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + while (inat_is_legacy_prefix(attr)) { + /* Skip if same prefix */ + for (i = 0; i < nb; i++) + if (prefixes->bytes[i] == b) + goto found; + if (nb == 4) + /* Invalid instruction */ + break; + prefixes->bytes[nb++] = b; + if (inat_is_address_size_prefix(attr)) { + /* address size switches 2/4 or 4/8 */ + if (insn->x86_64) + insn->addr_bytes ^= 12; + else + insn->addr_bytes ^= 6; + } else if (inat_is_operand_size_prefix(attr)) { + /* oprand size switches 2/4 */ + insn->opnd_bytes ^= 6; + } +found: + prefixes->nbytes++; + insn->next_byte++; + lb = b; + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + } + /* Set the last prefix */ + if (lb && lb != insn->prefixes.bytes[3]) { + if (unlikely(insn->prefixes.bytes[3])) { + /* Swap the last prefix */ + b = insn->prefixes.bytes[3]; + for (i = 0; i < nb; i++) + if (prefixes->bytes[i] == lb) + prefixes->bytes[i] = b; + } + insn->prefixes.bytes[3] = lb; + } + + /* Decode REX prefix */ + if (insn->x86_64) { + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + if (inat_is_rex_prefix(attr)) { + insn->rex_prefix.value = b; + insn->rex_prefix.nbytes = 1; + insn->next_byte++; + if (X86_REX_W(b)) + /* REX.W overrides opnd_size */ + insn->opnd_bytes = 8; + } + } + insn->rex_prefix.got = 1; + + /* Decode VEX prefix */ + b = peek_next(insn_byte_t, insn); + attr = inat_get_opcode_attribute(b); + if (inat_is_vex_prefix(attr)) { + insn_byte_t b2 = peek_nbyte_next(insn_byte_t, insn, 1); + if (!insn->x86_64) { + /* + * In 32-bits mode, if the [7:6] bits (mod bits of + * ModRM) on the second byte are not 11b, it is + * LDS or LES. + */ + if (X86_MODRM_MOD(b2) != 3) + goto vex_end; + } + insn->vex_prefix.bytes[0] = b; + insn->vex_prefix.bytes[1] = b2; + if (inat_is_vex3_prefix(attr)) { + b2 = peek_nbyte_next(insn_byte_t, insn, 2); + insn->vex_prefix.bytes[2] = b2; + insn->vex_prefix.nbytes = 3; + insn->next_byte += 3; + if (insn->x86_64 && X86_VEX_W(b2)) + /* VEX.W overrides opnd_size */ + insn->opnd_bytes = 8; + } else { + /* + * For VEX2, fake VEX3-like byte#2. + * Makes it easier to decode vex.W, vex.vvvv, + * vex.L and vex.pp. Masking with 0x7f sets vex.W == 0. + */ + insn->vex_prefix.bytes[2] = b2 & 0x7f; + insn->vex_prefix.nbytes = 2; + insn->next_byte += 2; + } + } +vex_end: + insn->vex_prefix.got = 1; + + prefixes->got = 1; + +err_out: + return; +} + +/** + * insn_get_opcode - collect opcode(s) + * @insn: &struct insn containing instruction + * + * Populates @insn->opcode, updates @insn->next_byte to point past the + * opcode byte(s), and set @insn->attr (except for groups). + * If necessary, first collects any preceding (prefix) bytes. + * Sets @insn->opcode.value = opcode1. No effect if @insn->opcode.got + * is already 1. + */ +void insn_get_opcode(struct insn *insn) +{ + struct insn_field *opcode = &insn->opcode; + insn_byte_t op; + int pfx_id; + if (opcode->got) + return; + if (!insn->prefixes.got) + insn_get_prefixes(insn); + + /* Get first opcode */ + op = get_next(insn_byte_t, insn); + opcode->bytes[0] = op; + opcode->nbytes = 1; + + /* Check if there is VEX prefix or not */ + if (insn_is_avx(insn)) { + insn_byte_t m, p; + m = insn_vex_m_bits(insn); + p = insn_vex_p_bits(insn); + insn->attr = inat_get_avx_attribute(op, m, p); + if (!inat_accept_vex(insn->attr) && !inat_is_group(insn->attr)) + insn->attr = 0; /* This instruction is bad */ + goto end; /* VEX has only 1 byte for opcode */ + } + + insn->attr = inat_get_opcode_attribute(op); + while (inat_is_escape(insn->attr)) { + /* Get escaped opcode */ + op = get_next(insn_byte_t, insn); + opcode->bytes[opcode->nbytes++] = op; + pfx_id = insn_last_prefix_id(insn); + insn->attr = inat_get_escape_attribute(op, pfx_id, insn->attr); + } + if (inat_must_vex(insn->attr)) + insn->attr = 0; /* This instruction is bad */ +end: + opcode->got = 1; + +err_out: + return; +} + +/** + * insn_get_modrm - collect ModRM byte, if any + * @insn: &struct insn containing instruction + * + * Populates @insn->modrm and updates @insn->next_byte to point past the + * ModRM byte, if any. If necessary, first collects the preceding bytes + * (prefixes and opcode(s)). No effect if @insn->modrm.got is already 1. + */ +void insn_get_modrm(struct insn *insn) +{ + struct insn_field *modrm = &insn->modrm; + insn_byte_t pfx_id, mod; + if (modrm->got) + return; + if (!insn->opcode.got) + insn_get_opcode(insn); + + if (inat_has_modrm(insn->attr)) { + mod = get_next(insn_byte_t, insn); + modrm->value = mod; + modrm->nbytes = 1; + if (inat_is_group(insn->attr)) { + pfx_id = insn_last_prefix_id(insn); + insn->attr = inat_get_group_attribute(mod, pfx_id, + insn->attr); + if (insn_is_avx(insn) && !inat_accept_vex(insn->attr)) + insn->attr = 0; /* This is bad */ + } + } + + if (insn->x86_64 && inat_is_force64(insn->attr)) + insn->opnd_bytes = 8; + modrm->got = 1; + +err_out: + return; +} + + +/** + * insn_rip_relative() - Does instruction use RIP-relative addressing mode? + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * ModRM byte. No effect if @insn->x86_64 is 0. + */ +int insn_rip_relative(struct insn *insn) +{ + struct insn_field *modrm = &insn->modrm; + + if (!insn->x86_64) + return 0; + if (!modrm->got) + insn_get_modrm(insn); + /* + * For rip-relative instructions, the mod field (top 2 bits) + * is zero and the r/m field (bottom 3 bits) is 0x5. + */ + return (modrm->nbytes && (modrm->value & 0xc7) == 0x5); +} + +/** + * insn_get_sib() - Get the SIB byte of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * ModRM byte. + */ +void insn_get_sib(struct insn *insn) +{ + insn_byte_t modrm; + + if (insn->sib.got) + return; + if (!insn->modrm.got) + insn_get_modrm(insn); + if (insn->modrm.nbytes) { + modrm = (insn_byte_t)insn->modrm.value; + if (insn->addr_bytes != 2 && + X86_MODRM_MOD(modrm) != 3 && X86_MODRM_RM(modrm) == 4) { + insn->sib.value = get_next(insn_byte_t, insn); + insn->sib.nbytes = 1; + } + } + insn->sib.got = 1; + +err_out: + return; +} + + +/** + * insn_get_displacement() - Get the displacement of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * SIB byte. + * Displacement value is sign-expanded. + */ +void insn_get_displacement(struct insn *insn) +{ + insn_byte_t mod, rm, base; + + if (insn->displacement.got) + return; + if (!insn->sib.got) + insn_get_sib(insn); + if (insn->modrm.nbytes) { + /* + * Interpreting the modrm byte: + * mod = 00 - no displacement fields (exceptions below) + * mod = 01 - 1-byte displacement field + * mod = 10 - displacement field is 4 bytes, or 2 bytes if + * address size = 2 (0x67 prefix in 32-bit mode) + * mod = 11 - no memory operand + * + * If address size = 2... + * mod = 00, r/m = 110 - displacement field is 2 bytes + * + * If address size != 2... + * mod != 11, r/m = 100 - SIB byte exists + * mod = 00, SIB base = 101 - displacement field is 4 bytes + * mod = 00, r/m = 101 - rip-relative addressing, displacement + * field is 4 bytes + */ + mod = X86_MODRM_MOD(insn->modrm.value); + rm = X86_MODRM_RM(insn->modrm.value); + base = X86_SIB_BASE(insn->sib.value); + if (mod == 3) + goto out; + if (mod == 1) { + insn->displacement.value = get_next(char, insn); + insn->displacement.nbytes = 1; + } else if (insn->addr_bytes == 2) { + if ((mod == 0 && rm == 6) || mod == 2) { + insn->displacement.value = + get_next(short, insn); + insn->displacement.nbytes = 2; + } + } else { + if ((mod == 0 && rm == 5) || mod == 2 || + (mod == 0 && base == 5)) { + insn->displacement.value = get_next(int, insn); + insn->displacement.nbytes = 4; + } + } + } +out: + insn->displacement.got = 1; + +err_out: + return; +} + +/* Decode moffset16/32/64. Return 0 if failed */ +static int __get_moffset(struct insn *insn) +{ + switch (insn->addr_bytes) { + case 2: + insn->moffset1.value = get_next(short, insn); + insn->moffset1.nbytes = 2; + break; + case 4: + insn->moffset1.value = get_next(int, insn); + insn->moffset1.nbytes = 4; + break; + case 8: + insn->moffset1.value = get_next(int, insn); + insn->moffset1.nbytes = 4; + insn->moffset2.value = get_next(int, insn); + insn->moffset2.nbytes = 4; + break; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + insn->moffset1.got = insn->moffset2.got = 1; + + return 1; + +err_out: + return 0; +} + +/* Decode imm v32(Iz). Return 0 if failed */ +static int __get_immv32(struct insn *insn) +{ + switch (insn->opnd_bytes) { + case 2: + insn->immediate.value = get_next(short, insn); + insn->immediate.nbytes = 2; + break; + case 4: + case 8: + insn->immediate.value = get_next(int, insn); + insn->immediate.nbytes = 4; + break; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + + return 1; + +err_out: + return 0; +} + +/* Decode imm v64(Iv/Ov), Return 0 if failed */ +static int __get_immv(struct insn *insn) +{ + switch (insn->opnd_bytes) { + case 2: + insn->immediate1.value = get_next(short, insn); + insn->immediate1.nbytes = 2; + break; + case 4: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + break; + case 8: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + insn->immediate2.value = get_next(int, insn); + insn->immediate2.nbytes = 4; + break; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + insn->immediate1.got = insn->immediate2.got = 1; + + return 1; +err_out: + return 0; +} + +/* Decode ptr16:16/32(Ap) */ +static int __get_immptr(struct insn *insn) +{ + switch (insn->opnd_bytes) { + case 2: + insn->immediate1.value = get_next(short, insn); + insn->immediate1.nbytes = 2; + break; + case 4: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + break; + case 8: + /* ptr16:64 is not exist (no segment) */ + return 0; + default: /* opnd_bytes must be modified manually */ + goto err_out; + } + insn->immediate2.value = get_next(unsigned short, insn); + insn->immediate2.nbytes = 2; + insn->immediate1.got = insn->immediate2.got = 1; + + return 1; +err_out: + return 0; +} + +/** + * insn_get_immediate() - Get the immediates of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * displacement bytes. + * Basically, most of immediates are sign-expanded. Unsigned-value can be + * get by bit masking with ((1 << (nbytes * 8)) - 1) + */ +void insn_get_immediate(struct insn *insn) +{ + if (insn->immediate.got) + return; + if (!insn->displacement.got) + insn_get_displacement(insn); + + if (inat_has_moffset(insn->attr)) { + if (!__get_moffset(insn)) + goto err_out; + goto done; + } + + if (!inat_has_immediate(insn->attr)) + /* no immediates */ + goto done; + + switch (inat_immediate_size(insn->attr)) { + case INAT_IMM_BYTE: + insn->immediate.value = get_next(char, insn); + insn->immediate.nbytes = 1; + break; + case INAT_IMM_WORD: + insn->immediate.value = get_next(short, insn); + insn->immediate.nbytes = 2; + break; + case INAT_IMM_DWORD: + insn->immediate.value = get_next(int, insn); + insn->immediate.nbytes = 4; + break; + case INAT_IMM_QWORD: + insn->immediate1.value = get_next(int, insn); + insn->immediate1.nbytes = 4; + insn->immediate2.value = get_next(int, insn); + insn->immediate2.nbytes = 4; + break; + case INAT_IMM_PTR: + if (!__get_immptr(insn)) + goto err_out; + break; + case INAT_IMM_VWORD32: + if (!__get_immv32(insn)) + goto err_out; + break; + case INAT_IMM_VWORD: + if (!__get_immv(insn)) + goto err_out; + break; + default: + /* Here, insn must have an immediate, but failed */ + goto err_out; + } + if (inat_has_second_immediate(insn->attr)) { + insn->immediate2.value = get_next(char, insn); + insn->immediate2.nbytes = 1; + } +done: + insn->immediate.got = 1; + +err_out: + return; +} + +/** + * insn_get_length() - Get the length of instruction + * @insn: &struct insn containing instruction + * + * If necessary, first collects the instruction up to and including the + * immediates bytes. + */ +void insn_get_length(struct insn *insn) +{ + if (insn->length) + return; + if (!insn->immediate.got) + insn_get_immediate(insn); + insn->length = (unsigned char)((unsigned long)insn->next_byte + - (unsigned long)insn->kaddr); +} diff --git a/tools/objtool/arch/x86/insn/insn.h b/tools/objtool/arch/x86/insn/insn.h new file mode 100644 index 0000000..dd12da0 --- /dev/null +++ b/tools/objtool/arch/x86/insn/insn.h @@ -0,0 +1,201 @@ +#ifndef _ASM_X86_INSN_H +#define _ASM_X86_INSN_H +/* + * x86 instruction analysis + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2009 + */ + +/* insn_attr_t is defined in inat.h */ +#include "inat.h" + +struct insn_field { + union { + insn_value_t value; + insn_byte_t bytes[4]; + }; + /* !0 if we've run insn_get_xxx() for this field */ + unsigned char got; + unsigned char nbytes; +}; + +struct insn { + struct insn_field prefixes; /* + * Prefixes + * prefixes.bytes[3]: last prefix + */ + struct insn_field rex_prefix; /* REX prefix */ + struct insn_field vex_prefix; /* VEX prefix */ + struct insn_field opcode; /* + * opcode.bytes[0]: opcode1 + * opcode.bytes[1]: opcode2 + * opcode.bytes[2]: opcode3 + */ + struct insn_field modrm; + struct insn_field sib; + struct insn_field displacement; + union { + struct insn_field immediate; + struct insn_field moffset1; /* for 64bit MOV */ + struct insn_field immediate1; /* for 64bit imm or off16/32 */ + }; + union { + struct insn_field moffset2; /* for 64bit MOV */ + struct insn_field immediate2; /* for 64bit imm or seg16 */ + }; + + insn_attr_t attr; + unsigned char opnd_bytes; + unsigned char addr_bytes; + unsigned char length; + unsigned char x86_64; + + const insn_byte_t *kaddr; /* kernel address of insn to analyze */ + const insn_byte_t *end_kaddr; /* kernel address of last insn in buffer */ + const insn_byte_t *next_byte; +}; + +#define MAX_INSN_SIZE 15 + +#define X86_MODRM_MOD(modrm) (((modrm) & 0xc0) >> 6) +#define X86_MODRM_REG(modrm) (((modrm) & 0x38) >> 3) +#define X86_MODRM_RM(modrm) ((modrm) & 0x07) + +#define X86_SIB_SCALE(sib) (((sib) & 0xc0) >> 6) +#define X86_SIB_INDEX(sib) (((sib) & 0x38) >> 3) +#define X86_SIB_BASE(sib) ((sib) & 0x07) + +#define X86_REX_W(rex) ((rex) & 8) +#define X86_REX_R(rex) ((rex) & 4) +#define X86_REX_X(rex) ((rex) & 2) +#define X86_REX_B(rex) ((rex) & 1) + +/* VEX bit flags */ +#define X86_VEX_W(vex) ((vex) & 0x80) /* VEX3 Byte2 */ +#define X86_VEX_R(vex) ((vex) & 0x80) /* VEX2/3 Byte1 */ +#define X86_VEX_X(vex) ((vex) & 0x40) /* VEX3 Byte1 */ +#define X86_VEX_B(vex) ((vex) & 0x20) /* VEX3 Byte1 */ +#define X86_VEX_L(vex) ((vex) & 0x04) /* VEX3 Byte2, VEX2 Byte1 */ +/* VEX bit fields */ +#define X86_VEX3_M(vex) ((vex) & 0x1f) /* VEX3 Byte1 */ +#define X86_VEX2_M 1 /* VEX2.M always 1 */ +#define X86_VEX_V(vex) (((vex) & 0x78) >> 3) /* VEX3 Byte2, VEX2 Byte1 */ +#define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */ +#define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */ + +extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64); +extern void insn_get_prefixes(struct insn *insn); +extern void insn_get_opcode(struct insn *insn); +extern void insn_get_modrm(struct insn *insn); +extern void insn_get_sib(struct insn *insn); +extern void insn_get_displacement(struct insn *insn); +extern void insn_get_immediate(struct insn *insn); +extern void insn_get_length(struct insn *insn); + +/* Attribute will be determined after getting ModRM (for opcode groups) */ +static inline void insn_get_attribute(struct insn *insn) +{ + insn_get_modrm(insn); +} + +/* Instruction uses RIP-relative addressing */ +extern int insn_rip_relative(struct insn *insn); + +/* Init insn for kernel text */ +static inline void kernel_insn_init(struct insn *insn, + const void *kaddr, int buf_len) +{ +#ifdef CONFIG_X86_64 + insn_init(insn, kaddr, buf_len, 1); +#else /* CONFIG_X86_32 */ + insn_init(insn, kaddr, buf_len, 0); +#endif +} + +static inline int insn_is_avx(struct insn *insn) +{ + if (!insn->prefixes.got) + insn_get_prefixes(insn); + return (insn->vex_prefix.value != 0); +} + +/* Ensure this instruction is decoded completely */ +static inline int insn_complete(struct insn *insn) +{ + return insn->opcode.got && insn->modrm.got && insn->sib.got && + insn->displacement.got && insn->immediate.got; +} + +static inline insn_byte_t insn_vex_m_bits(struct insn *insn) +{ + if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ + return X86_VEX2_M; + else + return X86_VEX3_M(insn->vex_prefix.bytes[1]); +} + +static inline insn_byte_t insn_vex_p_bits(struct insn *insn) +{ + if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */ + return X86_VEX_P(insn->vex_prefix.bytes[1]); + else + return X86_VEX_P(insn->vex_prefix.bytes[2]); +} + +/* Get the last prefix id from last prefix or VEX prefix */ +static inline int insn_last_prefix_id(struct insn *insn) +{ + if (insn_is_avx(insn)) + return insn_vex_p_bits(insn); /* VEX_p is a SIMD prefix id */ + + if (insn->prefixes.bytes[3]) + return inat_get_last_prefix_id(insn->prefixes.bytes[3]); + + return 0; +} + +/* Offset of each field from kaddr */ +static inline int insn_offset_rex_prefix(struct insn *insn) +{ + return insn->prefixes.nbytes; +} +static inline int insn_offset_vex_prefix(struct insn *insn) +{ + return insn_offset_rex_prefix(insn) + insn->rex_prefix.nbytes; +} +static inline int insn_offset_opcode(struct insn *insn) +{ + return insn_offset_vex_prefix(insn) + insn->vex_prefix.nbytes; +} +static inline int insn_offset_modrm(struct insn *insn) +{ + return insn_offset_opcode(insn) + insn->opcode.nbytes; +} +static inline int insn_offset_sib(struct insn *insn) +{ + return insn_offset_modrm(insn) + insn->modrm.nbytes; +} +static inline int insn_offset_displacement(struct insn *insn) +{ + return insn_offset_sib(insn) + insn->sib.nbytes; +} +static inline int insn_offset_immediate(struct insn *insn) +{ + return insn_offset_displacement(insn) + insn->displacement.nbytes; +} + +#endif /* _ASM_X86_INSN_H */ diff --git a/tools/objtool/arch/x86/insn/x86-opcode-map.txt b/tools/objtool/arch/x86/insn/x86-opcode-map.txt new file mode 100644 index 0000000..d388de7 --- /dev/null +++ b/tools/objtool/arch/x86/insn/x86-opcode-map.txt @@ -0,0 +1,984 @@ +# x86 Opcode Maps +# +# This is (mostly) based on following documentations. +# - Intel(R) 64 and IA-32 Architectures Software Developer's Manual Vol.2C +# (#326018-047US, June 2013) +# +#<Opcode maps> +# Table: table-name +# Referrer: escaped-name +# AVXcode: avx-code +# opcode: mnemonic|GrpXXX [operand1[,operand2...]] [(extra1)[,(extra2)...] [| 2nd-mnemonic ...] +# (or) +# opcode: escape # escaped-name +# EndTable +# +#<group maps> +# GrpTable: GrpXXX +# reg: mnemonic [operand1[,operand2...]] [(extra1)[,(extra2)...] [| 2nd-mnemonic ...] +# EndTable +# +# AVX Superscripts +# (v): this opcode requires VEX prefix. +# (v1): this opcode only supports 128bit VEX. +# +# Last Prefix Superscripts +# - (66): the last prefix is 0x66 +# - (F3): the last prefix is 0xF3 +# - (F2): the last prefix is 0xF2 +# - (!F3) : the last prefix is not 0xF3 (including non-last prefix case) +# - (66&F2): Both 0x66 and 0xF2 prefixes are specified. + +Table: one byte opcode +Referrer: +AVXcode: +# 0x00 - 0x0f +00: ADD Eb,Gb +01: ADD Ev,Gv +02: ADD Gb,Eb +03: ADD Gv,Ev +04: ADD AL,Ib +05: ADD rAX,Iz +06: PUSH ES (i64) +07: POP ES (i64) +08: OR Eb,Gb +09: OR Ev,Gv +0a: OR Gb,Eb +0b: OR Gv,Ev +0c: OR AL,Ib +0d: OR rAX,Iz +0e: PUSH CS (i64) +0f: escape # 2-byte escape +# 0x10 - 0x1f +10: ADC Eb,Gb +11: ADC Ev,Gv +12: ADC Gb,Eb +13: ADC Gv,Ev +14: ADC AL,Ib +15: ADC rAX,Iz +16: PUSH SS (i64) +17: POP SS (i64) +18: SBB Eb,Gb +19: SBB Ev,Gv +1a: SBB Gb,Eb +1b: SBB Gv,Ev +1c: SBB AL,Ib +1d: SBB rAX,Iz +1e: PUSH DS (i64) +1f: POP DS (i64) +# 0x20 - 0x2f +20: AND Eb,Gb +21: AND Ev,Gv +22: AND Gb,Eb +23: AND Gv,Ev +24: AND AL,Ib +25: AND rAx,Iz +26: SEG=ES (Prefix) +27: DAA (i64) +28: SUB Eb,Gb +29: SUB Ev,Gv +2a: SUB Gb,Eb +2b: SUB Gv,Ev +2c: SUB AL,Ib +2d: SUB rAX,Iz +2e: SEG=CS (Prefix) +2f: DAS (i64) +# 0x30 - 0x3f +30: XOR Eb,Gb +31: XOR Ev,Gv +32: XOR Gb,Eb +33: XOR Gv,Ev +34: XOR AL,Ib +35: XOR rAX,Iz +36: SEG=SS (Prefix) +37: AAA (i64) +38: CMP Eb,Gb +39: CMP Ev,Gv +3a: CMP Gb,Eb +3b: CMP Gv,Ev +3c: CMP AL,Ib +3d: CMP rAX,Iz +3e: SEG=DS (Prefix) +3f: AAS (i64) +# 0x40 - 0x4f +40: INC eAX (i64) | REX (o64) +41: INC eCX (i64) | REX.B (o64) +42: INC eDX (i64) | REX.X (o64) +43: INC eBX (i64) | REX.XB (o64) +44: INC eSP (i64) | REX.R (o64) +45: INC eBP (i64) | REX.RB (o64) +46: INC eSI (i64) | REX.RX (o64) +47: INC eDI (i64) | REX.RXB (o64) +48: DEC eAX (i64) | REX.W (o64) +49: DEC eCX (i64) | REX.WB (o64) +4a: DEC eDX (i64) | REX.WX (o64) +4b: DEC eBX (i64) | REX.WXB (o64) +4c: DEC eSP (i64) | REX.WR (o64) +4d: DEC eBP (i64) | REX.WRB (o64) +4e: DEC eSI (i64) | REX.WRX (o64) +4f: DEC eDI (i64) | REX.WRXB (o64) +# 0x50 - 0x5f +50: PUSH rAX/r8 (d64) +51: PUSH rCX/r9 (d64) +52: PUSH rDX/r10 (d64) +53: PUSH rBX/r11 (d64) +54: PUSH rSP/r12 (d64) +55: PUSH rBP/r13 (d64) +56: PUSH rSI/r14 (d64) +57: PUSH rDI/r15 (d64) +58: POP rAX/r8 (d64) +59: POP rCX/r9 (d64) +5a: POP rDX/r10 (d64) +5b: POP rBX/r11 (d64) +5c: POP rSP/r12 (d64) +5d: POP rBP/r13 (d64) +5e: POP rSI/r14 (d64) +5f: POP rDI/r15 (d64) +# 0x60 - 0x6f +60: PUSHA/PUSHAD (i64) +61: POPA/POPAD (i64) +62: BOUND Gv,Ma (i64) +63: ARPL Ew,Gw (i64) | MOVSXD Gv,Ev (o64) +64: SEG=FS (Prefix) +65: SEG=GS (Prefix) +66: Operand-Size (Prefix) +67: Address-Size (Prefix) +68: PUSH Iz (d64) +69: IMUL Gv,Ev,Iz +6a: PUSH Ib (d64) +6b: IMUL Gv,Ev,Ib +6c: INS/INSB Yb,DX +6d: INS/INSW/INSD Yz,DX +6e: OUTS/OUTSB DX,Xb +6f: OUTS/OUTSW/OUTSD DX,Xz +# 0x70 - 0x7f +70: JO Jb +71: JNO Jb +72: JB/JNAE/JC Jb +73: JNB/JAE/JNC Jb +74: JZ/JE Jb +75: JNZ/JNE Jb +76: JBE/JNA Jb +77: JNBE/JA Jb +78: JS Jb +79: JNS Jb +7a: JP/JPE Jb +7b: JNP/JPO Jb +7c: JL/JNGE Jb +7d: JNL/JGE Jb +7e: JLE/JNG Jb +7f: JNLE/JG Jb +# 0x80 - 0x8f +80: Grp1 Eb,Ib (1A) +81: Grp1 Ev,Iz (1A) +82: Grp1 Eb,Ib (1A),(i64) +83: Grp1 Ev,Ib (1A) +84: TEST Eb,Gb +85: TEST Ev,Gv +86: XCHG Eb,Gb +87: XCHG Ev,Gv +88: MOV Eb,Gb +89: MOV Ev,Gv +8a: MOV Gb,Eb +8b: MOV Gv,Ev +8c: MOV Ev,Sw +8d: LEA Gv,M +8e: MOV Sw,Ew +8f: Grp1A (1A) | POP Ev (d64) +# 0x90 - 0x9f +90: NOP | PAUSE (F3) | XCHG r8,rAX +91: XCHG rCX/r9,rAX +92: XCHG rDX/r10,rAX +93: XCHG rBX/r11,rAX +94: XCHG rSP/r12,rAX +95: XCHG rBP/r13,rAX +96: XCHG rSI/r14,rAX +97: XCHG rDI/r15,rAX +98: CBW/CWDE/CDQE +99: CWD/CDQ/CQO +9a: CALLF Ap (i64) +9b: FWAIT/WAIT +9c: PUSHF/D/Q Fv (d64) +9d: POPF/D/Q Fv (d64) +9e: SAHF +9f: LAHF +# 0xa0 - 0xaf +a0: MOV AL,Ob +a1: MOV rAX,Ov +a2: MOV Ob,AL +a3: MOV Ov,rAX +a4: MOVS/B Yb,Xb +a5: MOVS/W/D/Q Yv,Xv +a6: CMPS/B Xb,Yb +a7: CMPS/W/D Xv,Yv +a8: TEST AL,Ib +a9: TEST rAX,Iz +aa: STOS/B Yb,AL +ab: STOS/W/D/Q Yv,rAX +ac: LODS/B AL,Xb +ad: LODS/W/D/Q rAX,Xv +ae: SCAS/B AL,Yb +# Note: The May 2011 Intel manual shows Xv for the second parameter of the +# next instruction but Yv is correct +af: SCAS/W/D/Q rAX,Yv +# 0xb0 - 0xbf +b0: MOV AL/R8L,Ib +b1: MOV CL/R9L,Ib +b2: MOV DL/R10L,Ib +b3: MOV BL/R11L,Ib +b4: MOV AH/R12L,Ib +b5: MOV CH/R13L,Ib +b6: MOV DH/R14L,Ib +b7: MOV BH/R15L,Ib +b8: MOV rAX/r8,Iv +b9: MOV rCX/r9,Iv +ba: MOV rDX/r10,Iv +bb: MOV rBX/r11,Iv +bc: MOV rSP/r12,Iv +bd: MOV rBP/r13,Iv +be: MOV rSI/r14,Iv +bf: MOV rDI/r15,Iv +# 0xc0 - 0xcf +c0: Grp2 Eb,Ib (1A) +c1: Grp2 Ev,Ib (1A) +c2: RETN Iw (f64) +c3: RETN +c4: LES Gz,Mp (i64) | VEX+2byte (Prefix) +c5: LDS Gz,Mp (i64) | VEX+1byte (Prefix) +c6: Grp11A Eb,Ib (1A) +c7: Grp11B Ev,Iz (1A) +c8: ENTER Iw,Ib +c9: LEAVE (d64) +ca: RETF Iw +cb: RETF +cc: INT3 +cd: INT Ib +ce: INTO (i64) +cf: IRET/D/Q +# 0xd0 - 0xdf +d0: Grp2 Eb,1 (1A) +d1: Grp2 Ev,1 (1A) +d2: Grp2 Eb,CL (1A) +d3: Grp2 Ev,CL (1A) +d4: AAM Ib (i64) +d5: AAD Ib (i64) +d6: +d7: XLAT/XLATB +d8: ESC +d9: ESC +da: ESC +db: ESC +dc: ESC +dd: ESC +de: ESC +df: ESC +# 0xe0 - 0xef +# Note: "forced64" is Intel CPU behavior: they ignore 0x66 prefix +# in 64-bit mode. AMD CPUs accept 0x66 prefix, it causes RIP truncation +# to 16 bits. In 32-bit mode, 0x66 is accepted by both Intel and AMD. +e0: LOOPNE/LOOPNZ Jb (f64) +e1: LOOPE/LOOPZ Jb (f64) +e2: LOOP Jb (f64) +e3: JrCXZ Jb (f64) +e4: IN AL,Ib +e5: IN eAX,Ib +e6: OUT Ib,AL +e7: OUT Ib,eAX +# With 0x66 prefix in 64-bit mode, for AMD CPUs immediate offset +# in "near" jumps and calls is 16-bit. For CALL, +# push of return address is 16-bit wide, RSP is decremented by 2 +# but is not truncated to 16 bits, unlike RIP. +e8: CALL Jz (f64) +e9: JMP-near Jz (f64) +ea: JMP-far Ap (i64) +eb: JMP-short Jb (f64) +ec: IN AL,DX +ed: IN eAX,DX +ee: OUT DX,AL +ef: OUT DX,eAX +# 0xf0 - 0xff +f0: LOCK (Prefix) +f1: +f2: REPNE (Prefix) | XACQUIRE (Prefix) +f3: REP/REPE (Prefix) | XRELEASE (Prefix) +f4: HLT +f5: CMC +f6: Grp3_1 Eb (1A) +f7: Grp3_2 Ev (1A) +f8: CLC +f9: STC +fa: CLI +fb: STI +fc: CLD +fd: STD +fe: Grp4 (1A) +ff: Grp5 (1A) +EndTable + +Table: 2-byte opcode (0x0f) +Referrer: 2-byte escape +AVXcode: 1 +# 0x0f 0x00-0x0f +00: Grp6 (1A) +01: Grp7 (1A) +02: LAR Gv,Ew +03: LSL Gv,Ew +04: +05: SYSCALL (o64) +06: CLTS +07: SYSRET (o64) +08: INVD +09: WBINVD +0a: +0b: UD2 (1B) +0c: +# AMD's prefetch group. Intel supports prefetchw(/1) only. +0d: GrpP +0e: FEMMS +# 3DNow! uses the last imm byte as opcode extension. +0f: 3DNow! Pq,Qq,Ib +# 0x0f 0x10-0x1f +# NOTE: According to Intel SDM opcode map, vmovups and vmovupd has no operands +# but it actually has operands. And also, vmovss and vmovsd only accept 128bit. +# MOVSS/MOVSD has too many forms(3) on SDM. This map just shows a typical form. +# Many AVX instructions lack v1 superscript, according to Intel AVX-Prgramming +# Reference A.1 +10: vmovups Vps,Wps | vmovupd Vpd,Wpd (66) | vmovss Vx,Hx,Wss (F3),(v1) | vmovsd Vx,Hx,Wsd (F2),(v1) +11: vmovups Wps,Vps | vmovupd Wpd,Vpd (66) | vmovss Wss,Hx,Vss (F3),(v1) | vmovsd Wsd,Hx,Vsd (F2),(v1) +12: vmovlps Vq,Hq,Mq (v1) | vmovhlps Vq,Hq,Uq (v1) | vmovlpd Vq,Hq,Mq (66),(v1) | vmovsldup Vx,Wx (F3) | vmovddup Vx,Wx (F2) +13: vmovlps Mq,Vq (v1) | vmovlpd Mq,Vq (66),(v1) +14: vunpcklps Vx,Hx,Wx | vunpcklpd Vx,Hx,Wx (66) +15: vunpckhps Vx,Hx,Wx | vunpckhpd Vx,Hx,Wx (66) +16: vmovhps Vdq,Hq,Mq (v1) | vmovlhps Vdq,Hq,Uq (v1) | vmovhpd Vdq,Hq,Mq (66),(v1) | vmovshdup Vx,Wx (F3) +17: vmovhps Mq,Vq (v1) | vmovhpd Mq,Vq (66),(v1) +18: Grp16 (1A) +19: +# Intel SDM opcode map does not list MPX instructions. For now using Gv for +# bnd registers and Ev for everything else is OK because the instruction +# decoder does not use the information except as an indication that there is +# a ModR/M byte. +1a: BNDCL Gv,Ev (F3) | BNDCU Gv,Ev (F2) | BNDMOV Gv,Ev (66) | BNDLDX Gv,Ev +1b: BNDCN Gv,Ev (F2) | BNDMOV Ev,Gv (66) | BNDMK Gv,Ev (F3) | BNDSTX Ev,Gv +1c: +1d: +1e: +1f: NOP Ev +# 0x0f 0x20-0x2f +20: MOV Rd,Cd +21: MOV Rd,Dd +22: MOV Cd,Rd +23: MOV Dd,Rd +24: +25: +26: +27: +28: vmovaps Vps,Wps | vmovapd Vpd,Wpd (66) +29: vmovaps Wps,Vps | vmovapd Wpd,Vpd (66) +2a: cvtpi2ps Vps,Qpi | cvtpi2pd Vpd,Qpi (66) | vcvtsi2ss Vss,Hss,Ey (F3),(v1) | vcvtsi2sd Vsd,Hsd,Ey (F2),(v1) +2b: vmovntps Mps,Vps | vmovntpd Mpd,Vpd (66) +2c: cvttps2pi Ppi,Wps | cvttpd2pi Ppi,Wpd (66) | vcvttss2si Gy,Wss (F3),(v1) | vcvttsd2si Gy,Wsd (F2),(v1) +2d: cvtps2pi Ppi,Wps | cvtpd2pi Qpi,Wpd (66) | vcvtss2si Gy,Wss (F3),(v1) | vcvtsd2si Gy,Wsd (F2),(v1) +2e: vucomiss Vss,Wss (v1) | vucomisd Vsd,Wsd (66),(v1) +2f: vcomiss Vss,Wss (v1) | vcomisd Vsd,Wsd (66),(v1) +# 0x0f 0x30-0x3f +30: WRMSR +31: RDTSC +32: RDMSR +33: RDPMC +34: SYSENTER +35: SYSEXIT +36: +37: GETSEC +38: escape # 3-byte escape 1 +39: +3a: escape # 3-byte escape 2 +3b: +3c: +3d: +3e: +3f: +# 0x0f 0x40-0x4f +40: CMOVO Gv,Ev +41: CMOVNO Gv,Ev +42: CMOVB/C/NAE Gv,Ev +43: CMOVAE/NB/NC Gv,Ev +44: CMOVE/Z Gv,Ev +45: CMOVNE/NZ Gv,Ev +46: CMOVBE/NA Gv,Ev +47: CMOVA/NBE Gv,Ev +48: CMOVS Gv,Ev +49: CMOVNS Gv,Ev +4a: CMOVP/PE Gv,Ev +4b: CMOVNP/PO Gv,Ev +4c: CMOVL/NGE Gv,Ev +4d: CMOVNL/GE Gv,Ev +4e: CMOVLE/NG Gv,Ev +4f: CMOVNLE/G Gv,Ev +# 0x0f 0x50-0x5f +50: vmovmskps Gy,Ups | vmovmskpd Gy,Upd (66) +51: vsqrtps Vps,Wps | vsqrtpd Vpd,Wpd (66) | vsqrtss Vss,Hss,Wss (F3),(v1) | vsqrtsd Vsd,Hsd,Wsd (F2),(v1) +52: vrsqrtps Vps,Wps | vrsqrtss Vss,Hss,Wss (F3),(v1) +53: vrcpps Vps,Wps | vrcpss Vss,Hss,Wss (F3),(v1) +54: vandps Vps,Hps,Wps | vandpd Vpd,Hpd,Wpd (66) +55: vandnps Vps,Hps,Wps | vandnpd Vpd,Hpd,Wpd (66) +56: vorps Vps,Hps,Wps | vorpd Vpd,Hpd,Wpd (66) +57: vxorps Vps,Hps,Wps | vxorpd Vpd,Hpd,Wpd (66) +58: vaddps Vps,Hps,Wps | vaddpd Vpd,Hpd,Wpd (66) | vaddss Vss,Hss,Wss (F3),(v1) | vaddsd Vsd,Hsd,Wsd (F2),(v1) +59: vmulps Vps,Hps,Wps | vmulpd Vpd,Hpd,Wpd (66) | vmulss Vss,Hss,Wss (F3),(v1) | vmulsd Vsd,Hsd,Wsd (F2),(v1) +5a: vcvtps2pd Vpd,Wps | vcvtpd2ps Vps,Wpd (66) | vcvtss2sd Vsd,Hx,Wss (F3),(v1) | vcvtsd2ss Vss,Hx,Wsd (F2),(v1) +5b: vcvtdq2ps Vps,Wdq | vcvtps2dq Vdq,Wps (66) | vcvttps2dq Vdq,Wps (F3) +5c: vsubps Vps,Hps,Wps | vsubpd Vpd,Hpd,Wpd (66) | vsubss Vss,Hss,Wss (F3),(v1) | vsubsd Vsd,Hsd,Wsd (F2),(v1) +5d: vminps Vps,Hps,Wps | vminpd Vpd,Hpd,Wpd (66) | vminss Vss,Hss,Wss (F3),(v1) | vminsd Vsd,Hsd,Wsd (F2),(v1) +5e: vdivps Vps,Hps,Wps | vdivpd Vpd,Hpd,Wpd (66) | vdivss Vss,Hss,Wss (F3),(v1) | vdivsd Vsd,Hsd,Wsd (F2),(v1) +5f: vmaxps Vps,Hps,Wps | vmaxpd Vpd,Hpd,Wpd (66) | vmaxss Vss,Hss,Wss (F3),(v1) | vmaxsd Vsd,Hsd,Wsd (F2),(v1) +# 0x0f 0x60-0x6f +60: punpcklbw Pq,Qd | vpunpcklbw Vx,Hx,Wx (66),(v1) +61: punpcklwd Pq,Qd | vpunpcklwd Vx,Hx,Wx (66),(v1) +62: punpckldq Pq,Qd | vpunpckldq Vx,Hx,Wx (66),(v1) +63: packsswb Pq,Qq | vpacksswb Vx,Hx,Wx (66),(v1) +64: pcmpgtb Pq,Qq | vpcmpgtb Vx,Hx,Wx (66),(v1) +65: pcmpgtw Pq,Qq | vpcmpgtw Vx,Hx,Wx (66),(v1) +66: pcmpgtd Pq,Qq | vpcmpgtd Vx,Hx,Wx (66),(v1) +67: packuswb Pq,Qq | vpackuswb Vx,Hx,Wx (66),(v1) +68: punpckhbw Pq,Qd | vpunpckhbw Vx,Hx,Wx (66),(v1) +69: punpckhwd Pq,Qd | vpunpckhwd Vx,Hx,Wx (66),(v1) +6a: punpckhdq Pq,Qd | vpunpckhdq Vx,Hx,Wx (66),(v1) +6b: packssdw Pq,Qd | vpackssdw Vx,Hx,Wx (66),(v1) +6c: vpunpcklqdq Vx,Hx,Wx (66),(v1) +6d: vpunpckhqdq Vx,Hx,Wx (66),(v1) +6e: movd/q Pd,Ey | vmovd/q Vy,Ey (66),(v1) +6f: movq Pq,Qq | vmovdqa Vx,Wx (66) | vmovdqu Vx,Wx (F3) +# 0x0f 0x70-0x7f +70: pshufw Pq,Qq,Ib | vpshufd Vx,Wx,Ib (66),(v1) | vpshufhw Vx,Wx,Ib (F3),(v1) | vpshuflw Vx,Wx,Ib (F2),(v1) +71: Grp12 (1A) +72: Grp13 (1A) +73: Grp14 (1A) +74: pcmpeqb Pq,Qq | vpcmpeqb Vx,Hx,Wx (66),(v1) +75: pcmpeqw Pq,Qq | vpcmpeqw Vx,Hx,Wx (66),(v1) +76: pcmpeqd Pq,Qq | vpcmpeqd Vx,Hx,Wx (66),(v1) +# Note: Remove (v), because vzeroall and vzeroupper becomes emms without VEX. +77: emms | vzeroupper | vzeroall +78: VMREAD Ey,Gy +79: VMWRITE Gy,Ey +7a: +7b: +7c: vhaddpd Vpd,Hpd,Wpd (66) | vhaddps Vps,Hps,Wps (F2) +7d: vhsubpd Vpd,Hpd,Wpd (66) | vhsubps Vps,Hps,Wps (F2) +7e: movd/q Ey,Pd | vmovd/q Ey,Vy (66),(v1) | vmovq Vq,Wq (F3),(v1) +7f: movq Qq,Pq | vmovdqa Wx,Vx (66) | vmovdqu Wx,Vx (F3) +# 0x0f 0x80-0x8f +# Note: "forced64" is Intel CPU behavior (see comment about CALL insn). +80: JO Jz (f64) +81: JNO Jz (f64) +82: JB/JC/JNAE Jz (f64) +83: JAE/JNB/JNC Jz (f64) +84: JE/JZ Jz (f64) +85: JNE/JNZ Jz (f64) +86: JBE/JNA Jz (f64) +87: JA/JNBE Jz (f64) +88: JS Jz (f64) +89: JNS Jz (f64) +8a: JP/JPE Jz (f64) +8b: JNP/JPO Jz (f64) +8c: JL/JNGE Jz (f64) +8d: JNL/JGE Jz (f64) +8e: JLE/JNG Jz (f64) +8f: JNLE/JG Jz (f64) +# 0x0f 0x90-0x9f +90: SETO Eb +91: SETNO Eb +92: SETB/C/NAE Eb +93: SETAE/NB/NC Eb +94: SETE/Z Eb +95: SETNE/NZ Eb +96: SETBE/NA Eb +97: SETA/NBE Eb +98: SETS Eb +99: SETNS Eb +9a: SETP/PE Eb +9b: SETNP/PO Eb +9c: SETL/NGE Eb +9d: SETNL/GE Eb +9e: SETLE/NG Eb +9f: SETNLE/G Eb +# 0x0f 0xa0-0xaf +a0: PUSH FS (d64) +a1: POP FS (d64) +a2: CPUID +a3: BT Ev,Gv +a4: SHLD Ev,Gv,Ib +a5: SHLD Ev,Gv,CL +a6: GrpPDLK +a7: GrpRNG +a8: PUSH GS (d64) +a9: POP GS (d64) +aa: RSM +ab: BTS Ev,Gv +ac: SHRD Ev,Gv,Ib +ad: SHRD Ev,Gv,CL +ae: Grp15 (1A),(1C) +af: IMUL Gv,Ev +# 0x0f 0xb0-0xbf +b0: CMPXCHG Eb,Gb +b1: CMPXCHG Ev,Gv +b2: LSS Gv,Mp +b3: BTR Ev,Gv +b4: LFS Gv,Mp +b5: LGS Gv,Mp +b6: MOVZX Gv,Eb +b7: MOVZX Gv,Ew +b8: JMPE (!F3) | POPCNT Gv,Ev (F3) +b9: Grp10 (1A) +ba: Grp8 Ev,Ib (1A) +bb: BTC Ev,Gv +bc: BSF Gv,Ev (!F3) | TZCNT Gv,Ev (F3) +bd: BSR Gv,Ev (!F3) | LZCNT Gv,Ev (F3) +be: MOVSX Gv,Eb +bf: MOVSX Gv,Ew +# 0x0f 0xc0-0xcf +c0: XADD Eb,Gb +c1: XADD Ev,Gv +c2: vcmpps Vps,Hps,Wps,Ib | vcmppd Vpd,Hpd,Wpd,Ib (66) | vcmpss Vss,Hss,Wss,Ib (F3),(v1) | vcmpsd Vsd,Hsd,Wsd,Ib (F2),(v1) +c3: movnti My,Gy +c4: pinsrw Pq,Ry/Mw,Ib | vpinsrw Vdq,Hdq,Ry/Mw,Ib (66),(v1) +c5: pextrw Gd,Nq,Ib | vpextrw Gd,Udq,Ib (66),(v1) +c6: vshufps Vps,Hps,Wps,Ib | vshufpd Vpd,Hpd,Wpd,Ib (66) +c7: Grp9 (1A) +c8: BSWAP RAX/EAX/R8/R8D +c9: BSWAP RCX/ECX/R9/R9D +ca: BSWAP RDX/EDX/R10/R10D +cb: BSWAP RBX/EBX/R11/R11D +cc: BSWAP RSP/ESP/R12/R12D +cd: BSWAP RBP/EBP/R13/R13D +ce: BSWAP RSI/ESI/R14/R14D +cf: BSWAP RDI/EDI/R15/R15D +# 0x0f 0xd0-0xdf +d0: vaddsubpd Vpd,Hpd,Wpd (66) | vaddsubps Vps,Hps,Wps (F2) +d1: psrlw Pq,Qq | vpsrlw Vx,Hx,Wx (66),(v1) +d2: psrld Pq,Qq | vpsrld Vx,Hx,Wx (66),(v1) +d3: psrlq Pq,Qq | vpsrlq Vx,Hx,Wx (66),(v1) +d4: paddq Pq,Qq | vpaddq Vx,Hx,Wx (66),(v1) +d5: pmullw Pq,Qq | vpmullw Vx,Hx,Wx (66),(v1) +d6: vmovq Wq,Vq (66),(v1) | movq2dq Vdq,Nq (F3) | movdq2q Pq,Uq (F2) +d7: pmovmskb Gd,Nq | vpmovmskb Gd,Ux (66),(v1) +d8: psubusb Pq,Qq | vpsubusb Vx,Hx,Wx (66),(v1) +d9: psubusw Pq,Qq | vpsubusw Vx,Hx,Wx (66),(v1) +da: pminub Pq,Qq | vpminub Vx,Hx,Wx (66),(v1) +db: pand Pq,Qq | vpand Vx,Hx,Wx (66),(v1) +dc: paddusb Pq,Qq | vpaddusb Vx,Hx,Wx (66),(v1) +dd: paddusw Pq,Qq | vpaddusw Vx,Hx,Wx (66),(v1) +de: pmaxub Pq,Qq | vpmaxub Vx,Hx,Wx (66),(v1) +df: pandn Pq,Qq | vpandn Vx,Hx,Wx (66),(v1) +# 0x0f 0xe0-0xef +e0: pavgb Pq,Qq | vpavgb Vx,Hx,Wx (66),(v1) +e1: psraw Pq,Qq | vpsraw Vx,Hx,Wx (66),(v1) +e2: psrad Pq,Qq | vpsrad Vx,Hx,Wx (66),(v1) +e3: pavgw Pq,Qq | vpavgw Vx,Hx,Wx (66),(v1) +e4: pmulhuw Pq,Qq | vpmulhuw Vx,Hx,Wx (66),(v1) +e5: pmulhw Pq,Qq | vpmulhw Vx,Hx,Wx (66),(v1) +e6: vcvttpd2dq Vx,Wpd (66) | vcvtdq2pd Vx,Wdq (F3) | vcvtpd2dq Vx,Wpd (F2) +e7: movntq Mq,Pq | vmovntdq Mx,Vx (66) +e8: psubsb Pq,Qq | vpsubsb Vx,Hx,Wx (66),(v1) +e9: psubsw Pq,Qq | vpsubsw Vx,Hx,Wx (66),(v1) +ea: pminsw Pq,Qq | vpminsw Vx,Hx,Wx (66),(v1) +eb: por Pq,Qq | vpor Vx,Hx,Wx (66),(v1) +ec: paddsb Pq,Qq | vpaddsb Vx,Hx,Wx (66),(v1) +ed: paddsw Pq,Qq | vpaddsw Vx,Hx,Wx (66),(v1) +ee: pmaxsw Pq,Qq | vpmaxsw Vx,Hx,Wx (66),(v1) +ef: pxor Pq,Qq | vpxor Vx,Hx,Wx (66),(v1) +# 0x0f 0xf0-0xff +f0: vlddqu Vx,Mx (F2) +f1: psllw Pq,Qq | vpsllw Vx,Hx,Wx (66),(v1) +f2: pslld Pq,Qq | vpslld Vx,Hx,Wx (66),(v1) +f3: psllq Pq,Qq | vpsllq Vx,Hx,Wx (66),(v1) +f4: pmuludq Pq,Qq | vpmuludq Vx,Hx,Wx (66),(v1) +f5: pmaddwd Pq,Qq | vpmaddwd Vx,Hx,Wx (66),(v1) +f6: psadbw Pq,Qq | vpsadbw Vx,Hx,Wx (66),(v1) +f7: maskmovq Pq,Nq | vmaskmovdqu Vx,Ux (66),(v1) +f8: psubb Pq,Qq | vpsubb Vx,Hx,Wx (66),(v1) +f9: psubw Pq,Qq | vpsubw Vx,Hx,Wx (66),(v1) +fa: psubd Pq,Qq | vpsubd Vx,Hx,Wx (66),(v1) +fb: psubq Pq,Qq | vpsubq Vx,Hx,Wx (66),(v1) +fc: paddb Pq,Qq | vpaddb Vx,Hx,Wx (66),(v1) +fd: paddw Pq,Qq | vpaddw Vx,Hx,Wx (66),(v1) +fe: paddd Pq,Qq | vpaddd Vx,Hx,Wx (66),(v1) +ff: +EndTable + +Table: 3-byte opcode 1 (0x0f 0x38) +Referrer: 3-byte escape 1 +AVXcode: 2 +# 0x0f 0x38 0x00-0x0f +00: pshufb Pq,Qq | vpshufb Vx,Hx,Wx (66),(v1) +01: phaddw Pq,Qq | vphaddw Vx,Hx,Wx (66),(v1) +02: phaddd Pq,Qq | vphaddd Vx,Hx,Wx (66),(v1) +03: phaddsw Pq,Qq | vphaddsw Vx,Hx,Wx (66),(v1) +04: pmaddubsw Pq,Qq | vpmaddubsw Vx,Hx,Wx (66),(v1) +05: phsubw Pq,Qq | vphsubw Vx,Hx,Wx (66),(v1) +06: phsubd Pq,Qq | vphsubd Vx,Hx,Wx (66),(v1) +07: phsubsw Pq,Qq | vphsubsw Vx,Hx,Wx (66),(v1) +08: psignb Pq,Qq | vpsignb Vx,Hx,Wx (66),(v1) +09: psignw Pq,Qq | vpsignw Vx,Hx,Wx (66),(v1) +0a: psignd Pq,Qq | vpsignd Vx,Hx,Wx (66),(v1) +0b: pmulhrsw Pq,Qq | vpmulhrsw Vx,Hx,Wx (66),(v1) +0c: vpermilps Vx,Hx,Wx (66),(v) +0d: vpermilpd Vx,Hx,Wx (66),(v) +0e: vtestps Vx,Wx (66),(v) +0f: vtestpd Vx,Wx (66),(v) +# 0x0f 0x38 0x10-0x1f +10: pblendvb Vdq,Wdq (66) +11: +12: +13: vcvtph2ps Vx,Wx,Ib (66),(v) +14: blendvps Vdq,Wdq (66) +15: blendvpd Vdq,Wdq (66) +16: vpermps Vqq,Hqq,Wqq (66),(v) +17: vptest Vx,Wx (66) +18: vbroadcastss Vx,Wd (66),(v) +19: vbroadcastsd Vqq,Wq (66),(v) +1a: vbroadcastf128 Vqq,Mdq (66),(v) +1b: +1c: pabsb Pq,Qq | vpabsb Vx,Wx (66),(v1) +1d: pabsw Pq,Qq | vpabsw Vx,Wx (66),(v1) +1e: pabsd Pq,Qq | vpabsd Vx,Wx (66),(v1) +1f: +# 0x0f 0x38 0x20-0x2f +20: vpmovsxbw Vx,Ux/Mq (66),(v1) +21: vpmovsxbd Vx,Ux/Md (66),(v1) +22: vpmovsxbq Vx,Ux/Mw (66),(v1) +23: vpmovsxwd Vx,Ux/Mq (66),(v1) +24: vpmovsxwq Vx,Ux/Md (66),(v1) +25: vpmovsxdq Vx,Ux/Mq (66),(v1) +26: +27: +28: vpmuldq Vx,Hx,Wx (66),(v1) +29: vpcmpeqq Vx,Hx,Wx (66),(v1) +2a: vmovntdqa Vx,Mx (66),(v1) +2b: vpackusdw Vx,Hx,Wx (66),(v1) +2c: vmaskmovps Vx,Hx,Mx (66),(v) +2d: vmaskmovpd Vx,Hx,Mx (66),(v) +2e: vmaskmovps Mx,Hx,Vx (66),(v) +2f: vmaskmovpd Mx,Hx,Vx (66),(v) +# 0x0f 0x38 0x30-0x3f +30: vpmovzxbw Vx,Ux/Mq (66),(v1) +31: vpmovzxbd Vx,Ux/Md (66),(v1) +32: vpmovzxbq Vx,Ux/Mw (66),(v1) +33: vpmovzxwd Vx,Ux/Mq (66),(v1) +34: vpmovzxwq Vx,Ux/Md (66),(v1) +35: vpmovzxdq Vx,Ux/Mq (66),(v1) +36: vpermd Vqq,Hqq,Wqq (66),(v) +37: vpcmpgtq Vx,Hx,Wx (66),(v1) +38: vpminsb Vx,Hx,Wx (66),(v1) +39: vpminsd Vx,Hx,Wx (66),(v1) +3a: vpminuw Vx,Hx,Wx (66),(v1) +3b: vpminud Vx,Hx,Wx (66),(v1) +3c: vpmaxsb Vx,Hx,Wx (66),(v1) +3d: vpmaxsd Vx,Hx,Wx (66),(v1) +3e: vpmaxuw Vx,Hx,Wx (66),(v1) +3f: vpmaxud Vx,Hx,Wx (66),(v1) +# 0x0f 0x38 0x40-0x8f +40: vpmulld Vx,Hx,Wx (66),(v1) +41: vphminposuw Vdq,Wdq (66),(v1) +42: +43: +44: +45: vpsrlvd/q Vx,Hx,Wx (66),(v) +46: vpsravd Vx,Hx,Wx (66),(v) +47: vpsllvd/q Vx,Hx,Wx (66),(v) +# Skip 0x48-0x57 +58: vpbroadcastd Vx,Wx (66),(v) +59: vpbroadcastq Vx,Wx (66),(v) +5a: vbroadcasti128 Vqq,Mdq (66),(v) +# Skip 0x5b-0x77 +78: vpbroadcastb Vx,Wx (66),(v) +79: vpbroadcastw Vx,Wx (66),(v) +# Skip 0x7a-0x7f +80: INVEPT Gy,Mdq (66) +81: INVPID Gy,Mdq (66) +82: INVPCID Gy,Mdq (66) +8c: vpmaskmovd/q Vx,Hx,Mx (66),(v) +8e: vpmaskmovd/q Mx,Vx,Hx (66),(v) +# 0x0f 0x38 0x90-0xbf (FMA) +90: vgatherdd/q Vx,Hx,Wx (66),(v) +91: vgatherqd/q Vx,Hx,Wx (66),(v) +92: vgatherdps/d Vx,Hx,Wx (66),(v) +93: vgatherqps/d Vx,Hx,Wx (66),(v) +94: +95: +96: vfmaddsub132ps/d Vx,Hx,Wx (66),(v) +97: vfmsubadd132ps/d Vx,Hx,Wx (66),(v) +98: vfmadd132ps/d Vx,Hx,Wx (66),(v) +99: vfmadd132ss/d Vx,Hx,Wx (66),(v),(v1) +9a: vfmsub132ps/d Vx,Hx,Wx (66),(v) +9b: vfmsub132ss/d Vx,Hx,Wx (66),(v),(v1) +9c: vfnmadd132ps/d Vx,Hx,Wx (66),(v) +9d: vfnmadd132ss/d Vx,Hx,Wx (66),(v),(v1) +9e: vfnmsub132ps/d Vx,Hx,Wx (66),(v) +9f: vfnmsub132ss/d Vx,Hx,Wx (66),(v),(v1) +a6: vfmaddsub213ps/d Vx,Hx,Wx (66),(v) +a7: vfmsubadd213ps/d Vx,Hx,Wx (66),(v) +a8: vfmadd213ps/d Vx,Hx,Wx (66),(v) +a9: vfmadd213ss/d Vx,Hx,Wx (66),(v),(v1) +aa: vfmsub213ps/d Vx,Hx,Wx (66),(v) +ab: vfmsub213ss/d Vx,Hx,Wx (66),(v),(v1) +ac: vfnmadd213ps/d Vx,Hx,Wx (66),(v) +ad: vfnmadd213ss/d Vx,Hx,Wx (66),(v),(v1) +ae: vfnmsub213ps/d Vx,Hx,Wx (66),(v) +af: vfnmsub213ss/d Vx,Hx,Wx (66),(v),(v1) +b6: vfmaddsub231ps/d Vx,Hx,Wx (66),(v) +b7: vfmsubadd231ps/d Vx,Hx,Wx (66),(v) +b8: vfmadd231ps/d Vx,Hx,Wx (66),(v) +b9: vfmadd231ss/d Vx,Hx,Wx (66),(v),(v1) +ba: vfmsub231ps/d Vx,Hx,Wx (66),(v) +bb: vfmsub231ss/d Vx,Hx,Wx (66),(v),(v1) +bc: vfnmadd231ps/d Vx,Hx,Wx (66),(v) +bd: vfnmadd231ss/d Vx,Hx,Wx (66),(v),(v1) +be: vfnmsub231ps/d Vx,Hx,Wx (66),(v) +bf: vfnmsub231ss/d Vx,Hx,Wx (66),(v),(v1) +# 0x0f 0x38 0xc0-0xff +c8: sha1nexte Vdq,Wdq +c9: sha1msg1 Vdq,Wdq +ca: sha1msg2 Vdq,Wdq +cb: sha256rnds2 Vdq,Wdq +cc: sha256msg1 Vdq,Wdq +cd: sha256msg2 Vdq,Wdq +db: VAESIMC Vdq,Wdq (66),(v1) +dc: VAESENC Vdq,Hdq,Wdq (66),(v1) +dd: VAESENCLAST Vdq,Hdq,Wdq (66),(v1) +de: VAESDEC Vdq,Hdq,Wdq (66),(v1) +df: VAESDECLAST Vdq,Hdq,Wdq (66),(v1) +f0: MOVBE Gy,My | MOVBE Gw,Mw (66) | CRC32 Gd,Eb (F2) | CRC32 Gd,Eb (66&F2) +f1: MOVBE My,Gy | MOVBE Mw,Gw (66) | CRC32 Gd,Ey (F2) | CRC32 Gd,Ew (66&F2) +f2: ANDN Gy,By,Ey (v) +f3: Grp17 (1A) +f5: BZHI Gy,Ey,By (v) | PEXT Gy,By,Ey (F3),(v) | PDEP Gy,By,Ey (F2),(v) +f6: ADCX Gy,Ey (66) | ADOX Gy,Ey (F3) | MULX By,Gy,rDX,Ey (F2),(v) +f7: BEXTR Gy,Ey,By (v) | SHLX Gy,Ey,By (66),(v) | SARX Gy,Ey,By (F3),(v) | SHRX Gy,Ey,By (F2),(v) +EndTable + +Table: 3-byte opcode 2 (0x0f 0x3a) +Referrer: 3-byte escape 2 +AVXcode: 3 +# 0x0f 0x3a 0x00-0xff +00: vpermq Vqq,Wqq,Ib (66),(v) +01: vpermpd Vqq,Wqq,Ib (66),(v) +02: vpblendd Vx,Hx,Wx,Ib (66),(v) +03: +04: vpermilps Vx,Wx,Ib (66),(v) +05: vpermilpd Vx,Wx,Ib (66),(v) +06: vperm2f128 Vqq,Hqq,Wqq,Ib (66),(v) +07: +08: vroundps Vx,Wx,Ib (66) +09: vroundpd Vx,Wx,Ib (66) +0a: vroundss Vss,Wss,Ib (66),(v1) +0b: vroundsd Vsd,Wsd,Ib (66),(v1) +0c: vblendps Vx,Hx,Wx,Ib (66) +0d: vblendpd Vx,Hx,Wx,Ib (66) +0e: vpblendw Vx,Hx,Wx,Ib (66),(v1) +0f: palignr Pq,Qq,Ib | vpalignr Vx,Hx,Wx,Ib (66),(v1) +14: vpextrb Rd/Mb,Vdq,Ib (66),(v1) +15: vpextrw Rd/Mw,Vdq,Ib (66),(v1) +16: vpextrd/q Ey,Vdq,Ib (66),(v1) +17: vextractps Ed,Vdq,Ib (66),(v1) +18: vinsertf128 Vqq,Hqq,Wqq,Ib (66),(v) +19: vextractf128 Wdq,Vqq,Ib (66),(v) +1d: vcvtps2ph Wx,Vx,Ib (66),(v) +20: vpinsrb Vdq,Hdq,Ry/Mb,Ib (66),(v1) +21: vinsertps Vdq,Hdq,Udq/Md,Ib (66),(v1) +22: vpinsrd/q Vdq,Hdq,Ey,Ib (66),(v1) +38: vinserti128 Vqq,Hqq,Wqq,Ib (66),(v) +39: vextracti128 Wdq,Vqq,Ib (66),(v) +40: vdpps Vx,Hx,Wx,Ib (66) +41: vdppd Vdq,Hdq,Wdq,Ib (66),(v1) +42: vmpsadbw Vx,Hx,Wx,Ib (66),(v1) +44: vpclmulqdq Vdq,Hdq,Wdq,Ib (66),(v1) +46: vperm2i128 Vqq,Hqq,Wqq,Ib (66),(v) +4a: vblendvps Vx,Hx,Wx,Lx (66),(v) +4b: vblendvpd Vx,Hx,Wx,Lx (66),(v) +4c: vpblendvb Vx,Hx,Wx,Lx (66),(v1) +60: vpcmpestrm Vdq,Wdq,Ib (66),(v1) +61: vpcmpestri Vdq,Wdq,Ib (66),(v1) +62: vpcmpistrm Vdq,Wdq,Ib (66),(v1) +63: vpcmpistri Vdq,Wdq,Ib (66),(v1) +cc: sha1rnds4 Vdq,Wdq,Ib +df: VAESKEYGEN Vdq,Wdq,Ib (66),(v1) +f0: RORX Gy,Ey,Ib (F2),(v) +EndTable + +GrpTable: Grp1 +0: ADD +1: OR +2: ADC +3: SBB +4: AND +5: SUB +6: XOR +7: CMP +EndTable + +GrpTable: Grp1A +0: POP +EndTable + +GrpTable: Grp2 +0: ROL +1: ROR +2: RCL +3: RCR +4: SHL/SAL +5: SHR +6: +7: SAR +EndTable + +GrpTable: Grp3_1 +0: TEST Eb,Ib +1: +2: NOT Eb +3: NEG Eb +4: MUL AL,Eb +5: IMUL AL,Eb +6: DIV AL,Eb +7: IDIV AL,Eb +EndTable + +GrpTable: Grp3_2 +0: TEST Ev,Iz +1: +2: NOT Ev +3: NEG Ev +4: MUL rAX,Ev +5: IMUL rAX,Ev +6: DIV rAX,Ev +7: IDIV rAX,Ev +EndTable + +GrpTable: Grp4 +0: INC Eb +1: DEC Eb +EndTable + +GrpTable: Grp5 +0: INC Ev +1: DEC Ev +# Note: "forced64" is Intel CPU behavior (see comment about CALL insn). +2: CALLN Ev (f64) +3: CALLF Ep +4: JMPN Ev (f64) +5: JMPF Mp +6: PUSH Ev (d64) +7: +EndTable + +GrpTable: Grp6 +0: SLDT Rv/Mw +1: STR Rv/Mw +2: LLDT Ew +3: LTR Ew +4: VERR Ew +5: VERW Ew +EndTable + +GrpTable: Grp7 +0: SGDT Ms | VMCALL (001),(11B) | VMLAUNCH (010),(11B) | VMRESUME (011),(11B) | VMXOFF (100),(11B) +1: SIDT Ms | MONITOR (000),(11B) | MWAIT (001),(11B) | CLAC (010),(11B) | STAC (011),(11B) +2: LGDT Ms | XGETBV (000),(11B) | XSETBV (001),(11B) | VMFUNC (100),(11B) | XEND (101)(11B) | XTEST (110)(11B) +3: LIDT Ms +4: SMSW Mw/Rv +5: rdpkru (110),(11B) | wrpkru (111),(11B) +6: LMSW Ew +7: INVLPG Mb | SWAPGS (o64),(000),(11B) | RDTSCP (001),(11B) +EndTable + +GrpTable: Grp8 +4: BT +5: BTS +6: BTR +7: BTC +EndTable + +GrpTable: Grp9 +1: CMPXCHG8B/16B Mq/Mdq +3: xrstors +4: xsavec +5: xsaves +6: VMPTRLD Mq | VMCLEAR Mq (66) | VMXON Mq (F3) | RDRAND Rv (11B) +7: VMPTRST Mq | VMPTRST Mq (F3) | RDSEED Rv (11B) +EndTable + +GrpTable: Grp10 +EndTable + +# Grp11A and Grp11B are expressed as Grp11 in Intel SDM +GrpTable: Grp11A +0: MOV Eb,Ib +7: XABORT Ib (000),(11B) +EndTable + +GrpTable: Grp11B +0: MOV Eb,Iz +7: XBEGIN Jz (000),(11B) +EndTable + +GrpTable: Grp12 +2: psrlw Nq,Ib (11B) | vpsrlw Hx,Ux,Ib (66),(11B),(v1) +4: psraw Nq,Ib (11B) | vpsraw Hx,Ux,Ib (66),(11B),(v1) +6: psllw Nq,Ib (11B) | vpsllw Hx,Ux,Ib (66),(11B),(v1) +EndTable + +GrpTable: Grp13 +2: psrld Nq,Ib (11B) | vpsrld Hx,Ux,Ib (66),(11B),(v1) +4: psrad Nq,Ib (11B) | vpsrad Hx,Ux,Ib (66),(11B),(v1) +6: pslld Nq,Ib (11B) | vpslld Hx,Ux,Ib (66),(11B),(v1) +EndTable + +GrpTable: Grp14 +2: psrlq Nq,Ib (11B) | vpsrlq Hx,Ux,Ib (66),(11B),(v1) +3: vpsrldq Hx,Ux,Ib (66),(11B),(v1) +6: psllq Nq,Ib (11B) | vpsllq Hx,Ux,Ib (66),(11B),(v1) +7: vpslldq Hx,Ux,Ib (66),(11B),(v1) +EndTable + +GrpTable: Grp15 +0: fxsave | RDFSBASE Ry (F3),(11B) +1: fxstor | RDGSBASE Ry (F3),(11B) +2: vldmxcsr Md (v1) | WRFSBASE Ry (F3),(11B) +3: vstmxcsr Md (v1) | WRGSBASE Ry (F3),(11B) +4: XSAVE +5: XRSTOR | lfence (11B) +6: XSAVEOPT | clwb (66) | mfence (11B) +7: clflush | clflushopt (66) | sfence (11B) | pcommit (66),(11B) +EndTable + +GrpTable: Grp16 +0: prefetch NTA +1: prefetch T0 +2: prefetch T1 +3: prefetch T2 +EndTable + +GrpTable: Grp17 +1: BLSR By,Ey (v) +2: BLSMSK By,Ey (v) +3: BLSI By,Ey (v) +EndTable + +# AMD's Prefetch Group +GrpTable: GrpP +0: PREFETCH +1: PREFETCHW +EndTable + +GrpTable: GrpPDLK +0: MONTMUL +1: XSHA1 +2: XSHA2 +EndTable + +GrpTable: GrpRNG +0: xstore-rng +1: xcrypt-ecb +2: xcrypt-cbc +4: xcrypt-cfb +5: xcrypt-ofb +EndTable diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c new file mode 100644 index 0000000..f7e0eba --- /dev/null +++ b/tools/objtool/builtin-check.c @@ -0,0 +1,1072 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +/* + * objtool check: + * + * This command analyzes every .o file and ensures the validity of its stack + * trace metadata. It enforces a set of rules on asm code and C inline + * assembly code so that stack traces can be reliable. + * + * For more information, see tools/objtool/Documentation/stack-validation.txt. + */ + +#include <string.h> +#include <subcmd/parse-options.h> + +#include "builtin.h" +#include "elf.h" +#include "special.h" +#include "arch.h" +#include "warn.h" + +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) + +#define STATE_FP_SAVED 0x1 +#define STATE_FP_SETUP 0x2 +#define STATE_FENTRY 0x4 + +struct instruction { + struct list_head list; + struct section *sec; + unsigned long offset; + unsigned int len, state; + unsigned char type; + unsigned long immediate; + bool alt_group, visited; + struct symbol *call_dest; + struct instruction *jump_dest; + struct list_head alts; +}; + +struct alternative { + struct list_head list; + struct instruction *insn; +}; + +struct objtool_file { + struct elf *elf; + struct list_head insns; +}; + +const char *objname; +static bool nofp; + +static struct instruction *find_instruction(struct objtool_file *file, + struct section *sec, + unsigned long offset) +{ + struct instruction *insn; + + list_for_each_entry(insn, &file->insns, list) + if (insn->sec == sec && insn->offset == offset) + return insn; + + return NULL; +} + +/* + * Check if the function has been manually whitelisted with the + * STACK_FRAME_NON_STANDARD macro, or if it should be automatically whitelisted + * due to its use of a context switching instruction. + */ +static bool ignore_func(struct objtool_file *file, struct symbol *func) +{ + struct section *macro_sec; + struct rela *rela; + struct instruction *insn; + + /* check for STACK_FRAME_NON_STANDARD */ + macro_sec = find_section_by_name(file->elf, "__func_stack_frame_non_standard"); + if (macro_sec && macro_sec->rela) + list_for_each_entry(rela, ¯o_sec->rela->relas, list) + if (rela->sym->sec == func->sec && + rela->addend == func->offset) + return true; + + /* check if it has a context switching instruction */ + insn = find_instruction(file, func->sec, func->offset); + if (!insn) + return false; + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func->offset + func->len) + break; + if (insn->type == INSN_CONTEXT_SWITCH) + return true; + } + + return false; +} + +/* + * This checks to see if the given function is a "noreturn" function. + * + * For global functions which are outside the scope of this object file, we + * have to keep a manual list of them. + * + * For local functions, we have to detect them manually by simply looking for + * the lack of a return instruction. + */ +static bool dead_end_function(struct objtool_file *file, struct symbol *func) +{ + int i; + struct instruction *insn; + bool empty = true; + + /* + * Unfortunately these have to be hard coded because the noreturn + * attribute isn't provided in ELF data. + */ + static const char * const global_noreturns[] = { + "__stack_chk_fail", + "panic", + "do_exit", + "__module_put_and_exit", + "complete_and_exit", + "kvm_spurious_fault", + "__reiserfs_panic", + "lbug_with_loc" + }; + + if (func->bind == STB_WEAK) + return false; + + if (func->bind == STB_GLOBAL) + for (i = 0; i < ARRAY_SIZE(global_noreturns); i++) + if (!strcmp(func->name, global_noreturns[i])) + return true; + + if (!func->sec) + return false; + + insn = find_instruction(file, func->sec, func->offset); + if (!insn) + return false; + + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func->offset + func->len) + break; + + empty = false; + + if (insn->type == INSN_RETURN) + return false; + + if (insn->type == INSN_JUMP_UNCONDITIONAL) { + struct instruction *dest = insn->jump_dest; + struct symbol *dest_func; + + if (!dest) + /* sibling call to another file */ + return false; + + if (dest->sec != func->sec || + dest->offset < func->offset || + dest->offset >= func->offset + func->len) { + /* local sibling call */ + dest_func = find_symbol_by_offset(dest->sec, + dest->offset); + if (!dest_func) + continue; + + return dead_end_function(file, dest_func); + } + } + + if (insn->type == INSN_JUMP_DYNAMIC) + /* sibling call */ + return false; + } + + return !empty; +} + +/* + * Call the arch-specific instruction decoder for all the instructions and add + * them to the global insns list. + */ +static int decode_instructions(struct objtool_file *file) +{ + struct section *sec; + unsigned long offset; + struct instruction *insn; + int ret; + + INIT_LIST_HEAD(&file->insns); + + list_for_each_entry(sec, &file->elf->sections, list) { + + if (!(sec->sh.sh_flags & SHF_EXECINSTR)) + continue; + + for (offset = 0; offset < sec->len; offset += insn->len) { + insn = malloc(sizeof(*insn)); + memset(insn, 0, sizeof(*insn)); + + INIT_LIST_HEAD(&insn->alts); + insn->sec = sec; + insn->offset = offset; + + ret = arch_decode_instruction(file->elf, sec, offset, + sec->len - offset, + &insn->len, &insn->type, + &insn->immediate); + if (ret) + return ret; + + if (!insn->type || insn->type > INSN_LAST) { + WARN_FUNC("invalid instruction type %d", + insn->sec, insn->offset, insn->type); + return -1; + } + + list_add_tail(&insn->list, &file->insns); + } + } + + return 0; +} + +/* + * Warnings shouldn't be reported for ignored functions. + */ +static void get_ignores(struct objtool_file *file) +{ + struct instruction *insn; + struct section *sec; + struct symbol *func; + + list_for_each_entry(sec, &file->elf->sections, list) { + list_for_each_entry(func, &sec->symbols, list) { + if (func->type != STT_FUNC) + continue; + + if (!ignore_func(file, func)) + continue; + + insn = find_instruction(file, sec, func->offset); + if (!insn) + continue; + + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func->offset + func->len) + break; + + insn->visited = true; + } + } + } +} + +/* + * Find the destination instructions for all jumps. + */ +static int get_jump_destinations(struct objtool_file *file) +{ + struct instruction *insn; + struct rela *rela; + struct section *dest_sec; + unsigned long dest_off; + + list_for_each_entry(insn, &file->insns, list) { + if (insn->type != INSN_JUMP_CONDITIONAL && + insn->type != INSN_JUMP_UNCONDITIONAL) + continue; + + /* skip ignores */ + if (insn->visited) + continue; + + rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!rela) { + dest_sec = insn->sec; + dest_off = insn->offset + insn->len + insn->immediate; + } else if (rela->sym->type == STT_SECTION) { + dest_sec = rela->sym->sec; + dest_off = rela->addend + 4; + } else if (rela->sym->sec->idx) { + dest_sec = rela->sym->sec; + dest_off = rela->sym->sym.st_value + rela->addend + 4; + } else { + /* sibling call */ + insn->jump_dest = 0; + continue; + } + + insn->jump_dest = find_instruction(file, dest_sec, dest_off); + if (!insn->jump_dest) { + + /* + * This is a special case where an alt instruction + * jumps past the end of the section. These are + * handled later in handle_group_alt(). + */ + if (!strcmp(insn->sec->name, ".altinstr_replacement")) + continue; + + WARN_FUNC("can't find jump dest instruction at %s+0x%lx", + insn->sec, insn->offset, dest_sec->name, + dest_off); + return -1; + } + } + + return 0; +} + +/* + * Find the destination instructions for all calls. + */ +static int get_call_destinations(struct objtool_file *file) +{ + struct instruction *insn; + unsigned long dest_off; + struct rela *rela; + + list_for_each_entry(insn, &file->insns, list) { + if (insn->type != INSN_CALL) + continue; + + rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!rela) { + dest_off = insn->offset + insn->len + insn->immediate; + insn->call_dest = find_symbol_by_offset(insn->sec, + dest_off); + if (!insn->call_dest) { + WARN_FUNC("can't find call dest symbol at offset 0x%lx", + insn->sec, insn->offset, dest_off); + return -1; + } + } else if (rela->sym->type == STT_SECTION) { + insn->call_dest = find_symbol_by_offset(rela->sym->sec, + rela->addend+4); + if (!insn->call_dest || + insn->call_dest->type != STT_FUNC) { + WARN_FUNC("can't find call dest symbol at %s+0x%x", + insn->sec, insn->offset, + rela->sym->sec->name, + rela->addend + 4); + return -1; + } + } else + insn->call_dest = rela->sym; + } + + return 0; +} + +/* + * The .alternatives section requires some extra special care, over and above + * what other special sections require: + * + * 1. Because alternatives are patched in-place, we need to insert a fake jump + * instruction at the end so that validate_branch() skips all the original + * replaced instructions when validating the new instruction path. + * + * 2. An added wrinkle is that the new instruction length might be zero. In + * that case the old instructions are replaced with noops. We simulate that + * by creating a fake jump as the only new instruction. + * + * 3. In some cases, the alternative section includes an instruction which + * conditionally jumps to the _end_ of the entry. We have to modify these + * jumps' destinations to point back to .text rather than the end of the + * entry in .altinstr_replacement. + * + * 4. It has been requested that we don't validate the !POPCNT feature path + * which is a "very very small percentage of machines". + */ +static int handle_group_alt(struct objtool_file *file, + struct special_alt *special_alt, + struct instruction *orig_insn, + struct instruction **new_insn) +{ + struct instruction *last_orig_insn, *last_new_insn, *insn, *fake_jump; + unsigned long dest_off; + + last_orig_insn = NULL; + insn = orig_insn; + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != special_alt->orig_sec || + insn->offset >= special_alt->orig_off + special_alt->orig_len) + break; + + if (special_alt->skip_orig) + insn->type = INSN_NOP; + + insn->alt_group = true; + last_orig_insn = insn; + } + + if (list_is_last(&last_orig_insn->list, &file->insns) || + list_next_entry(last_orig_insn, list)->sec != special_alt->orig_sec) { + WARN("%s: don't know how to handle alternatives at end of section", + special_alt->orig_sec->name); + return -1; + } + + fake_jump = malloc(sizeof(*fake_jump)); + if (!fake_jump) { + WARN("malloc failed"); + return -1; + } + memset(fake_jump, 0, sizeof(*fake_jump)); + INIT_LIST_HEAD(&fake_jump->alts); + fake_jump->sec = special_alt->new_sec; + fake_jump->offset = -1; + fake_jump->type = INSN_JUMP_UNCONDITIONAL; + fake_jump->jump_dest = list_next_entry(last_orig_insn, list); + + if (!special_alt->new_len) { + *new_insn = fake_jump; + return 0; + } + + last_new_insn = NULL; + insn = *new_insn; + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != special_alt->new_sec || + insn->offset >= special_alt->new_off + special_alt->new_len) + break; + + last_new_insn = insn; + + if (insn->type != INSN_JUMP_CONDITIONAL && + insn->type != INSN_JUMP_UNCONDITIONAL) + continue; + + if (!insn->immediate) + continue; + + dest_off = insn->offset + insn->len + insn->immediate; + if (dest_off == special_alt->new_off + special_alt->new_len) + insn->jump_dest = fake_jump; + + if (!insn->jump_dest) { + WARN_FUNC("can't find alternative jump destination", + insn->sec, insn->offset); + return -1; + } + } + + if (!last_new_insn) { + WARN_FUNC("can't find last new alternative instruction", + special_alt->new_sec, special_alt->new_off); + return -1; + } + + list_add(&fake_jump->list, &last_new_insn->list); + + return 0; +} + +/* + * A jump table entry can either convert a nop to a jump or a jump to a nop. + * If the original instruction is a jump, make the alt entry an effective nop + * by just skipping the original instruction. + */ +static int handle_jump_alt(struct objtool_file *file, + struct special_alt *special_alt, + struct instruction *orig_insn, + struct instruction **new_insn) +{ + if (orig_insn->type == INSN_NOP) + return 0; + + if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) { + WARN_FUNC("unsupported instruction at jump label", + orig_insn->sec, orig_insn->offset); + return -1; + } + + *new_insn = list_next_entry(orig_insn, list); + return 0; +} + +/* + * Read all the special sections which have alternate instructions which can be + * patched in or redirected to at runtime. Each instruction having alternate + * instruction(s) has them added to its insn->alts list, which will be + * traversed in validate_branch(). + */ +static int get_special_section_alts(struct objtool_file *file) +{ + struct list_head special_alts; + struct instruction *orig_insn, *new_insn; + struct special_alt *special_alt, *tmp; + struct alternative *alt; + int ret; + + ret = special_get_alts(file->elf, &special_alts); + if (ret) + return ret; + + list_for_each_entry_safe(special_alt, tmp, &special_alts, list) { + alt = malloc(sizeof(*alt)); + if (!alt) { + WARN("malloc failed"); + ret = -1; + goto out; + } + + orig_insn = find_instruction(file, special_alt->orig_sec, + special_alt->orig_off); + if (!orig_insn) { + WARN_FUNC("special: can't find orig instruction", + special_alt->orig_sec, special_alt->orig_off); + ret = -1; + goto out; + } + + new_insn = NULL; + if (!special_alt->group || special_alt->new_len) { + new_insn = find_instruction(file, special_alt->new_sec, + special_alt->new_off); + if (!new_insn) { + WARN_FUNC("special: can't find new instruction", + special_alt->new_sec, + special_alt->new_off); + ret = -1; + goto out; + } + } + + if (special_alt->group) { + ret = handle_group_alt(file, special_alt, orig_insn, + &new_insn); + if (ret) + goto out; + } else if (special_alt->jump_or_nop) { + ret = handle_jump_alt(file, special_alt, orig_insn, + &new_insn); + if (ret) + goto out; + } + + alt->insn = new_insn; + list_add_tail(&alt->list, &orig_insn->alts); + + list_del(&special_alt->list); + free(special_alt); + } + +out: + return ret; +} + +/* + * For some switch statements, gcc generates a jump table in the .rodata + * section which contains a list of addresses within the function to jump to. + * This finds these jump tables and adds them to the insn->alts lists. + */ +static int get_switch_alts(struct objtool_file *file) +{ + struct instruction *insn, *alt_insn; + struct rela *rodata_rela, *rela; + struct section *rodata; + struct symbol *func; + struct alternative *alt; + + list_for_each_entry(insn, &file->insns, list) { + if (insn->type != INSN_JUMP_DYNAMIC) + continue; + + rodata_rela = find_rela_by_dest_range(insn->sec, insn->offset, + insn->len); + if (!rodata_rela || strcmp(rodata_rela->sym->name, ".rodata")) + continue; + + rodata = find_section_by_name(file->elf, ".rodata"); + if (!rodata || !rodata->rela) + continue; + + /* common case: jmpq *[addr](,%rax,8) */ + rela = find_rela_by_dest(rodata, rodata_rela->addend); + + /* rare case: jmpq *[addr](%rip) */ + if (!rela) + rela = find_rela_by_dest(rodata, + rodata_rela->addend + 4); + if (!rela) + continue; + + func = find_containing_func(insn->sec, insn->offset); + if (!func) { + WARN_FUNC("can't find containing func", + insn->sec, insn->offset); + return -1; + } + + list_for_each_entry_from(rela, &rodata->rela->relas, list) { + if (rela->sym->sec != insn->sec || + rela->addend <= func->offset || + rela->addend >= func->offset + func->len) + break; + + alt_insn = find_instruction(file, insn->sec, + rela->addend); + if (!alt_insn) { + WARN("%s: can't find instruction at %s+0x%x", + rodata->rela->name, insn->sec->name, + rela->addend); + return -1; + } + + alt = malloc(sizeof(*alt)); + if (!alt) { + WARN("malloc failed"); + return -1; + } + + alt->insn = alt_insn; + list_add_tail(&alt->list, &insn->alts); + } + } + + return 0; +} + +static int decode_sections(struct objtool_file *file) +{ + int ret; + + ret = decode_instructions(file); + if (ret) + return ret; + + get_ignores(file); + + ret = get_jump_destinations(file); + if (ret) + return ret; + + ret = get_call_destinations(file); + if (ret) + return ret; + + ret = get_special_section_alts(file); + if (ret) + return ret; + + ret = get_switch_alts(file); + if (ret) + return ret; + + return 0; +} + +static bool is_fentry_call(struct instruction *insn) +{ + if (insn->type == INSN_CALL && + insn->call_dest->type == STT_NOTYPE && + !strcmp(insn->call_dest->name, "__fentry__")) + return true; + + return false; +} + +static bool has_modified_stack_frame(struct instruction *insn) +{ + return (insn->state & STATE_FP_SAVED) || + (insn->state & STATE_FP_SETUP); +} + +static bool has_valid_stack_frame(struct instruction *insn) +{ + return (insn->state & STATE_FP_SAVED) && + (insn->state & STATE_FP_SETUP); +} + +/* + * Follow the branch starting at the given instruction, and recursively follow + * any other branches (jumps). Meanwhile, track the frame pointer state at + * each instruction and validate all the rules described in + * tools/objtool/Documentation/stack-validation.txt. + */ +static int validate_branch(struct objtool_file *file, + struct instruction *first, unsigned char first_state) +{ + struct alternative *alt; + struct instruction *insn; + struct section *sec; + unsigned char state; + int ret, warnings = 0; + + insn = first; + sec = insn->sec; + state = first_state; + + if (insn->alt_group && list_empty(&insn->alts)) { + WARN_FUNC("don't know how to handle branch to middle of alternative instruction group", + sec, insn->offset); + warnings++; + } + + while (1) { + if (insn->visited) { + if (insn->state != state) { + WARN_FUNC("frame pointer state mismatch", + sec, insn->offset); + warnings++; + } + + return warnings; + } + + /* + * Catch a rare case where a noreturn function falls through to + * the next function. + */ + if (is_fentry_call(insn) && (state & STATE_FENTRY)) + return warnings; + + insn->visited = true; + insn->state = state; + + list_for_each_entry(alt, &insn->alts, list) { + ret = validate_branch(file, alt->insn, state); + warnings += ret; + } + + switch (insn->type) { + + case INSN_FP_SAVE: + if (!nofp) { + if (state & STATE_FP_SAVED) { + WARN_FUNC("duplicate frame pointer save", + sec, insn->offset); + warnings++; + } + state |= STATE_FP_SAVED; + } + break; + + case INSN_FP_SETUP: + if (!nofp) { + if (state & STATE_FP_SETUP) { + WARN_FUNC("duplicate frame pointer setup", + sec, insn->offset); + warnings++; + } + state |= STATE_FP_SETUP; + } + break; + + case INSN_FP_RESTORE: + if (!nofp) { + if (has_valid_stack_frame(insn)) + state &= ~STATE_FP_SETUP; + + state &= ~STATE_FP_SAVED; + } + break; + + case INSN_RETURN: + if (!nofp && has_modified_stack_frame(insn)) { + WARN_FUNC("return without frame pointer restore", + sec, insn->offset); + warnings++; + } + return warnings; + + case INSN_CALL: + if (is_fentry_call(insn)) { + state |= STATE_FENTRY; + break; + } + + if (dead_end_function(file, insn->call_dest)) + return warnings; + + /* fallthrough */ + case INSN_CALL_DYNAMIC: + if (!nofp && !has_valid_stack_frame(insn)) { + WARN_FUNC("call without frame pointer save/setup", + sec, insn->offset); + warnings++; + } + break; + + case INSN_JUMP_CONDITIONAL: + case INSN_JUMP_UNCONDITIONAL: + if (insn->jump_dest) { + ret = validate_branch(file, insn->jump_dest, + state); + warnings += ret; + } else if (has_modified_stack_frame(insn)) { + WARN_FUNC("sibling call from callable instruction with changed frame pointer", + sec, insn->offset); + warnings++; + } /* else it's a sibling call */ + + if (insn->type == INSN_JUMP_UNCONDITIONAL) + return warnings; + + break; + + case INSN_JUMP_DYNAMIC: + if (list_empty(&insn->alts) && + has_modified_stack_frame(insn)) { + WARN_FUNC("sibling call from callable instruction with changed frame pointer", + sec, insn->offset); + warnings++; + } + + return warnings; + + case INSN_BUG: + return warnings; + + default: + break; + } + + insn = list_next_entry(insn, list); + + if (&insn->list == &file->insns || insn->sec != sec) { + WARN("%s: unexpected end of section", sec->name); + warnings++; + return warnings; + } + } + + return warnings; +} + +static bool is_gcov_insn(struct instruction *insn) +{ + struct rela *rela; + struct section *sec; + struct symbol *sym; + unsigned long offset; + + rela = find_rela_by_dest_range(insn->sec, insn->offset, insn->len); + if (!rela) + return false; + + if (rela->sym->type != STT_SECTION) + return false; + + sec = rela->sym->sec; + offset = rela->addend + insn->offset + insn->len - rela->offset; + + list_for_each_entry(sym, &sec->symbols, list) { + if (sym->type != STT_OBJECT) + continue; + + if (offset >= sym->offset && offset < sym->offset + sym->len) + return (!memcmp(sym->name, "__gcov0.", 8)); + } + + return false; +} + +static bool is_kasan_insn(struct instruction *insn) +{ + return (insn->type == INSN_CALL && + !strcmp(insn->call_dest->name, "__asan_handle_no_return")); +} + +static bool is_ubsan_insn(struct instruction *insn) +{ + return (insn->type == INSN_CALL && + !strcmp(insn->call_dest->name, + "__ubsan_handle_builtin_unreachable")); +} + +static bool ignore_unreachable_insn(struct instruction *insn, + unsigned long func_end) +{ + int i; + + if (insn->type == INSN_NOP) + return true; + + if (is_gcov_insn(insn)) + return true; + + /* + * Check if this (or a subsequent) instruction is related to + * CONFIG_UBSAN or CONFIG_KASAN. + * + * End the search at 5 instructions to avoid going into the weeds. + */ + for (i = 0; i < 5; i++) { + + if (is_kasan_insn(insn) || is_ubsan_insn(insn)) + return true; + + if (insn->type == INSN_JUMP_UNCONDITIONAL && insn->jump_dest) { + insn = insn->jump_dest; + continue; + } + + if (insn->offset + insn->len >= func_end) + break; + insn = list_next_entry(insn, list); + } + + return false; +} + +static int validate_functions(struct objtool_file *file) +{ + struct section *sec; + struct symbol *func; + struct instruction *insn; + unsigned long func_end; + int ret, warnings = 0; + + list_for_each_entry(sec, &file->elf->sections, list) { + list_for_each_entry(func, &sec->symbols, list) { + if (func->type != STT_FUNC) + continue; + + insn = find_instruction(file, sec, func->offset); + if (!insn) { + WARN("%s(): can't find starting instruction", + func->name); + warnings++; + continue; + } + + ret = validate_branch(file, insn, 0); + warnings += ret; + } + } + + list_for_each_entry(sec, &file->elf->sections, list) { + list_for_each_entry(func, &sec->symbols, list) { + if (func->type != STT_FUNC) + continue; + + insn = find_instruction(file, sec, func->offset); + if (!insn) + continue; + + func_end = func->offset + func->len; + + list_for_each_entry_from(insn, &file->insns, list) { + if (insn->sec != func->sec || + insn->offset >= func_end) + break; + + if (insn->visited) + continue; + + if (!ignore_unreachable_insn(insn, func_end)) { + WARN_FUNC("function has unreachable instruction", insn->sec, insn->offset); + warnings++; + } + + insn->visited = true; + } + } + } + + return warnings; +} + +static int validate_uncallable_instructions(struct objtool_file *file) +{ + struct instruction *insn; + int warnings = 0; + + list_for_each_entry(insn, &file->insns, list) { + if (!insn->visited && insn->type == INSN_RETURN) { + WARN_FUNC("return instruction outside of a callable function", + insn->sec, insn->offset); + warnings++; + } + } + + return warnings; +} + +static void cleanup(struct objtool_file *file) +{ + struct instruction *insn, *tmpinsn; + struct alternative *alt, *tmpalt; + + list_for_each_entry_safe(insn, tmpinsn, &file->insns, list) { + list_for_each_entry_safe(alt, tmpalt, &insn->alts, list) { + list_del(&alt->list); + free(alt); + } + list_del(&insn->list); + free(insn); + } + elf_close(file->elf); +} + +const char * const check_usage[] = { + "objtool check [<options>] file.o", + NULL, +}; + +int cmd_check(int argc, const char **argv) +{ + struct objtool_file file; + int ret, warnings = 0; + + const struct option options[] = { + OPT_BOOLEAN('f', "no-fp", &nofp, "Skip frame pointer validation"), + OPT_END(), + }; + + argc = parse_options(argc, argv, options, check_usage, 0); + + if (argc != 1) + usage_with_options(check_usage, options); + + objname = argv[0]; + + file.elf = elf_open(objname); + if (!file.elf) { + fprintf(stderr, "error reading elf file %s\n", objname); + return 1; + } + + INIT_LIST_HEAD(&file.insns); + + ret = decode_sections(&file); + if (ret < 0) + goto out; + warnings += ret; + + ret = validate_functions(&file); + if (ret < 0) + goto out; + warnings += ret; + + ret = validate_uncallable_instructions(&file); + if (ret < 0) + goto out; + warnings += ret; + +out: + cleanup(&file); + + /* ignore warnings for now until we get all the code cleaned up */ + if (ret || warnings) + return 0; + return 0; +} diff --git a/tools/objtool/builtin.h b/tools/objtool/builtin.h new file mode 100644 index 0000000..34d2ba7 --- /dev/null +++ b/tools/objtool/builtin.h @@ -0,0 +1,22 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ +#ifndef _BUILTIN_H +#define _BUILTIN_H + +extern int cmd_check(int argc, const char **argv); + +#endif /* _BUILTIN_H */ diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c new file mode 100644 index 0000000..d547e3f --- /dev/null +++ b/tools/objtool/elf.c @@ -0,0 +1,403 @@ +/* + * elf.c - ELF access library + * + * Adapted from kpatch (https://github.com/dynup/kpatch): + * Copyright (C) 2013-2015 Josh Poimboeuf <jpoimboe@redhat.com> + * Copyright (C) 2014 Seth Jennings <sjenning@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "elf.h" +#include "warn.h" + +struct section *find_section_by_name(struct elf *elf, const char *name) +{ + struct section *sec; + + list_for_each_entry(sec, &elf->sections, list) + if (!strcmp(sec->name, name)) + return sec; + + return NULL; +} + +static struct section *find_section_by_index(struct elf *elf, + unsigned int idx) +{ + struct section *sec; + + list_for_each_entry(sec, &elf->sections, list) + if (sec->idx == idx) + return sec; + + return NULL; +} + +static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx) +{ + struct section *sec; + struct symbol *sym; + + list_for_each_entry(sec, &elf->sections, list) + list_for_each_entry(sym, &sec->symbols, list) + if (sym->idx == idx) + return sym; + + return NULL; +} + +struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset) +{ + struct symbol *sym; + + list_for_each_entry(sym, &sec->symbols, list) + if (sym->type != STT_SECTION && + sym->offset == offset) + return sym; + + return NULL; +} + +struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset, + unsigned int len) +{ + struct rela *rela; + + if (!sec->rela) + return NULL; + + list_for_each_entry(rela, &sec->rela->relas, list) + if (rela->offset >= offset && rela->offset < offset + len) + return rela; + + return NULL; +} + +struct rela *find_rela_by_dest(struct section *sec, unsigned long offset) +{ + return find_rela_by_dest_range(sec, offset, 1); +} + +struct symbol *find_containing_func(struct section *sec, unsigned long offset) +{ + struct symbol *func; + + list_for_each_entry(func, &sec->symbols, list) + if (func->type == STT_FUNC && offset >= func->offset && + offset < func->offset + func->len) + return func; + + return NULL; +} + +static int read_sections(struct elf *elf) +{ + Elf_Scn *s = NULL; + struct section *sec; + size_t shstrndx, sections_nr; + int i; + + if (elf_getshdrnum(elf->elf, §ions_nr)) { + perror("elf_getshdrnum"); + return -1; + } + + if (elf_getshdrstrndx(elf->elf, &shstrndx)) { + perror("elf_getshdrstrndx"); + return -1; + } + + for (i = 0; i < sections_nr; i++) { + sec = malloc(sizeof(*sec)); + if (!sec) { + perror("malloc"); + return -1; + } + memset(sec, 0, sizeof(*sec)); + + INIT_LIST_HEAD(&sec->symbols); + INIT_LIST_HEAD(&sec->relas); + + list_add_tail(&sec->list, &elf->sections); + + s = elf_getscn(elf->elf, i); + if (!s) { + perror("elf_getscn"); + return -1; + } + + sec->idx = elf_ndxscn(s); + + if (!gelf_getshdr(s, &sec->sh)) { + perror("gelf_getshdr"); + return -1; + } + + sec->name = elf_strptr(elf->elf, shstrndx, sec->sh.sh_name); + if (!sec->name) { + perror("elf_strptr"); + return -1; + } + + sec->elf_data = elf_getdata(s, NULL); + if (!sec->elf_data) { + perror("elf_getdata"); + return -1; + } + + if (sec->elf_data->d_off != 0 || + sec->elf_data->d_size != sec->sh.sh_size) { + WARN("unexpected data attributes for %s", sec->name); + return -1; + } + + sec->data = (unsigned long)sec->elf_data->d_buf; + sec->len = sec->elf_data->d_size; + } + + /* sanity check, one more call to elf_nextscn() should return NULL */ + if (elf_nextscn(elf->elf, s)) { + WARN("section entry mismatch"); + return -1; + } + + return 0; +} + +static int read_symbols(struct elf *elf) +{ + struct section *symtab; + struct symbol *sym; + struct list_head *entry, *tmp; + int symbols_nr, i; + + symtab = find_section_by_name(elf, ".symtab"); + if (!symtab) { + WARN("missing symbol table"); + return -1; + } + + symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize; + + for (i = 0; i < symbols_nr; i++) { + sym = malloc(sizeof(*sym)); + if (!sym) { + perror("malloc"); + return -1; + } + memset(sym, 0, sizeof(*sym)); + + sym->idx = i; + + if (!gelf_getsym(symtab->elf_data, i, &sym->sym)) { + perror("gelf_getsym"); + goto err; + } + + sym->name = elf_strptr(elf->elf, symtab->sh.sh_link, + sym->sym.st_name); + if (!sym->name) { + perror("elf_strptr"); + goto err; + } + + sym->type = GELF_ST_TYPE(sym->sym.st_info); + sym->bind = GELF_ST_BIND(sym->sym.st_info); + + if (sym->sym.st_shndx > SHN_UNDEF && + sym->sym.st_shndx < SHN_LORESERVE) { + sym->sec = find_section_by_index(elf, + sym->sym.st_shndx); + if (!sym->sec) { + WARN("couldn't find section for symbol %s", + sym->name); + goto err; + } + if (sym->type == STT_SECTION) { + sym->name = sym->sec->name; + sym->sec->sym = sym; + } + } else + sym->sec = find_section_by_index(elf, 0); + + sym->offset = sym->sym.st_value; + sym->len = sym->sym.st_size; + + /* sorted insert into a per-section list */ + entry = &sym->sec->symbols; + list_for_each_prev(tmp, &sym->sec->symbols) { + struct symbol *s; + + s = list_entry(tmp, struct symbol, list); + + if (sym->offset > s->offset) { + entry = tmp; + break; + } + + if (sym->offset == s->offset && sym->len >= s->len) { + entry = tmp; + break; + } + } + list_add(&sym->list, entry); + } + + return 0; + +err: + free(sym); + return -1; +} + +static int read_relas(struct elf *elf) +{ + struct section *sec; + struct rela *rela; + int i; + unsigned int symndx; + + list_for_each_entry(sec, &elf->sections, list) { + if (sec->sh.sh_type != SHT_RELA) + continue; + + sec->base = find_section_by_name(elf, sec->name + 5); + if (!sec->base) { + WARN("can't find base section for rela section %s", + sec->name); + return -1; + } + + sec->base->rela = sec; + + for (i = 0; i < sec->sh.sh_size / sec->sh.sh_entsize; i++) { + rela = malloc(sizeof(*rela)); + if (!rela) { + perror("malloc"); + return -1; + } + memset(rela, 0, sizeof(*rela)); + + list_add_tail(&rela->list, &sec->relas); + + if (!gelf_getrela(sec->elf_data, i, &rela->rela)) { + perror("gelf_getrela"); + return -1; + } + + rela->type = GELF_R_TYPE(rela->rela.r_info); + rela->addend = rela->rela.r_addend; + rela->offset = rela->rela.r_offset; + symndx = GELF_R_SYM(rela->rela.r_info); + rela->sym = find_symbol_by_index(elf, symndx); + if (!rela->sym) { + WARN("can't find rela entry symbol %d for %s", + symndx, sec->name); + return -1; + } + } + } + + return 0; +} + +struct elf *elf_open(const char *name) +{ + struct elf *elf; + + elf_version(EV_CURRENT); + + elf = malloc(sizeof(*elf)); + if (!elf) { + perror("malloc"); + return NULL; + } + memset(elf, 0, sizeof(*elf)); + + INIT_LIST_HEAD(&elf->sections); + + elf->name = strdup(name); + if (!elf->name) { + perror("strdup"); + goto err; + } + + elf->fd = open(name, O_RDONLY); + if (elf->fd == -1) { + perror("open"); + goto err; + } + + elf->elf = elf_begin(elf->fd, ELF_C_READ_MMAP, NULL); + if (!elf->elf) { + perror("elf_begin"); + goto err; + } + + if (!gelf_getehdr(elf->elf, &elf->ehdr)) { + perror("gelf_getehdr"); + goto err; + } + + if (read_sections(elf)) + goto err; + + if (read_symbols(elf)) + goto err; + + if (read_relas(elf)) + goto err; + + return elf; + +err: + elf_close(elf); + return NULL; +} + +void elf_close(struct elf *elf) +{ + struct section *sec, *tmpsec; + struct symbol *sym, *tmpsym; + struct rela *rela, *tmprela; + + list_for_each_entry_safe(sec, tmpsec, &elf->sections, list) { + list_for_each_entry_safe(sym, tmpsym, &sec->symbols, list) { + list_del(&sym->list); + free(sym); + } + list_for_each_entry_safe(rela, tmprela, &sec->relas, list) { + list_del(&rela->list); + free(rela); + } + list_del(&sec->list); + free(sec); + } + if (elf->name) + free(elf->name); + if (elf->fd > 0) + close(elf->fd); + if (elf->elf) + elf_end(elf->elf); + free(elf); +} diff --git a/tools/objtool/elf.h b/tools/objtool/elf.h new file mode 100644 index 0000000..66919de --- /dev/null +++ b/tools/objtool/elf.h @@ -0,0 +1,79 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef _OBJTOOL_ELF_H +#define _OBJTOOL_ELF_H + +#include <stdio.h> +#include <gelf.h> +#include <linux/list.h> + +struct section { + struct list_head list; + GElf_Shdr sh; + struct list_head symbols; + struct list_head relas; + struct section *base, *rela; + struct symbol *sym; + Elf_Data *elf_data; + char *name; + int idx; + unsigned long data; + unsigned int len; +}; + +struct symbol { + struct list_head list; + GElf_Sym sym; + struct section *sec; + char *name; + int idx; + unsigned char bind, type; + unsigned long offset; + unsigned int len; +}; + +struct rela { + struct list_head list; + GElf_Rela rela; + struct symbol *sym; + unsigned int type; + int offset; + int addend; +}; + +struct elf { + Elf *elf; + GElf_Ehdr ehdr; + int fd; + char *name; + struct list_head sections; +}; + + +struct elf *elf_open(const char *name); +struct section *find_section_by_name(struct elf *elf, const char *name); +struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset); +struct rela *find_rela_by_dest(struct section *sec, unsigned long offset); +struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset, + unsigned int len); +struct symbol *find_containing_func(struct section *sec, unsigned long offset); +void elf_close(struct elf *elf); + + + +#endif /* _OBJTOOL_ELF_H */ diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c new file mode 100644 index 0000000..46c326d --- /dev/null +++ b/tools/objtool/objtool.c @@ -0,0 +1,136 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +/* + * objtool: + * + * The 'check' subcmd analyzes every .o file and ensures the validity of its + * stack trace metadata. It enforces a set of rules on asm code and C inline + * assembly code so that stack traces can be reliable. + * + * For more information, see tools/objtool/Documentation/stack-validation.txt. + */ + +#include <stdio.h> +#include <stdbool.h> +#include <string.h> +#include <stdlib.h> +#include <subcmd/exec-cmd.h> +#include <subcmd/pager.h> + +#include "builtin.h" + +#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0])) + +struct cmd_struct { + const char *name; + int (*fn)(int, const char **); + const char *help; +}; + +static const char objtool_usage_string[] = + "objtool [OPTIONS] COMMAND [ARGS]"; + +static struct cmd_struct objtool_cmds[] = { + {"check", cmd_check, "Perform stack metadata validation on an object file" }, +}; + +bool help; + +static void cmd_usage(void) +{ + unsigned int i, longest = 0; + + printf("\n usage: %s\n\n", objtool_usage_string); + + for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) { + if (longest < strlen(objtool_cmds[i].name)) + longest = strlen(objtool_cmds[i].name); + } + + puts(" Commands:"); + for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) { + printf(" %-*s ", longest, objtool_cmds[i].name); + puts(objtool_cmds[i].help); + } + + printf("\n"); + + exit(1); +} + +static void handle_options(int *argc, const char ***argv) +{ + while (*argc > 0) { + const char *cmd = (*argv)[0]; + + if (cmd[0] != '-') + break; + + if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h")) { + help = true; + break; + } else { + fprintf(stderr, "Unknown option: %s\n", cmd); + fprintf(stderr, "\n Usage: %s\n", + objtool_usage_string); + exit(1); + } + + (*argv)++; + (*argc)--; + } +} + +static void handle_internal_command(int argc, const char **argv) +{ + const char *cmd = argv[0]; + unsigned int i, ret; + + for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) { + struct cmd_struct *p = objtool_cmds+i; + + if (strcmp(p->name, cmd)) + continue; + + ret = p->fn(argc, argv); + + exit(ret); + } + + cmd_usage(); +} + +int main(int argc, const char **argv) +{ + static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED"; + + /* libsubcmd init */ + exec_cmd_init("objtool", UNUSED, UNUSED, UNUSED); + pager_init(UNUSED); + + argv++; + argc--; + handle_options(&argc, &argv); + + if (!argc || help) + cmd_usage(); + + handle_internal_command(argc, argv); + + return 0; +} diff --git a/tools/objtool/special.c b/tools/objtool/special.c new file mode 100644 index 0000000..bff8abb --- /dev/null +++ b/tools/objtool/special.c @@ -0,0 +1,193 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +/* + * This file reads all the special sections which have alternate instructions + * which can be patched in or redirected to at runtime. + */ + +#include <stdlib.h> +#include <string.h> + +#include "special.h" +#include "warn.h" + +#define EX_ENTRY_SIZE 12 +#define EX_ORIG_OFFSET 0 +#define EX_NEW_OFFSET 4 + +#define JUMP_ENTRY_SIZE 24 +#define JUMP_ORIG_OFFSET 0 +#define JUMP_NEW_OFFSET 8 + +#define ALT_ENTRY_SIZE 13 +#define ALT_ORIG_OFFSET 0 +#define ALT_NEW_OFFSET 4 +#define ALT_FEATURE_OFFSET 8 +#define ALT_ORIG_LEN_OFFSET 10 +#define ALT_NEW_LEN_OFFSET 11 + +#define X86_FEATURE_POPCNT (4*32+23) + +struct special_entry { + const char *sec; + bool group, jump_or_nop; + unsigned char size, orig, new; + unsigned char orig_len, new_len; /* group only */ + unsigned char feature; /* ALTERNATIVE macro CPU feature */ +}; + +struct special_entry entries[] = { + { + .sec = ".altinstructions", + .group = true, + .size = ALT_ENTRY_SIZE, + .orig = ALT_ORIG_OFFSET, + .orig_len = ALT_ORIG_LEN_OFFSET, + .new = ALT_NEW_OFFSET, + .new_len = ALT_NEW_LEN_OFFSET, + .feature = ALT_FEATURE_OFFSET, + }, + { + .sec = "__jump_table", + .jump_or_nop = true, + .size = JUMP_ENTRY_SIZE, + .orig = JUMP_ORIG_OFFSET, + .new = JUMP_NEW_OFFSET, + }, + { + .sec = "__ex_table", + .size = EX_ENTRY_SIZE, + .orig = EX_ORIG_OFFSET, + .new = EX_NEW_OFFSET, + }, + {}, +}; + +static int get_alt_entry(struct elf *elf, struct special_entry *entry, + struct section *sec, int idx, + struct special_alt *alt) +{ + struct rela *orig_rela, *new_rela; + unsigned long offset; + + offset = idx * entry->size; + + alt->group = entry->group; + alt->jump_or_nop = entry->jump_or_nop; + + if (alt->group) { + alt->orig_len = *(unsigned char *)(sec->data + offset + + entry->orig_len); + alt->new_len = *(unsigned char *)(sec->data + offset + + entry->new_len); + } + + if (entry->feature) { + unsigned short feature; + + feature = *(unsigned short *)(sec->data + offset + + entry->feature); + + /* + * It has been requested that we don't validate the !POPCNT + * feature path which is a "very very small percentage of + * machines". + */ + if (feature == X86_FEATURE_POPCNT) + alt->skip_orig = true; + } + + orig_rela = find_rela_by_dest(sec, offset + entry->orig); + if (!orig_rela) { + WARN_FUNC("can't find orig rela", sec, offset + entry->orig); + return -1; + } + if (orig_rela->sym->type != STT_SECTION) { + WARN_FUNC("don't know how to handle non-section rela symbol %s", + sec, offset + entry->orig, orig_rela->sym->name); + return -1; + } + + alt->orig_sec = orig_rela->sym->sec; + alt->orig_off = orig_rela->addend; + + if (!entry->group || alt->new_len) { + new_rela = find_rela_by_dest(sec, offset + entry->new); + if (!new_rela) { + WARN_FUNC("can't find new rela", + sec, offset + entry->new); + return -1; + } + + alt->new_sec = new_rela->sym->sec; + alt->new_off = (unsigned int)new_rela->addend; + + /* _ASM_EXTABLE_EX hack */ + if (alt->new_off >= 0x7ffffff0) + alt->new_off -= 0x7ffffff0; + } + + return 0; +} + +/* + * Read all the special sections and create a list of special_alt structs which + * describe all the alternate instructions which can be patched in or + * redirected to at runtime. + */ +int special_get_alts(struct elf *elf, struct list_head *alts) +{ + struct special_entry *entry; + struct section *sec; + unsigned int nr_entries; + struct special_alt *alt; + int idx, ret; + + INIT_LIST_HEAD(alts); + + for (entry = entries; entry->sec; entry++) { + sec = find_section_by_name(elf, entry->sec); + if (!sec) + continue; + + if (sec->len % entry->size != 0) { + WARN("%s size not a multiple of %d", + sec->name, entry->size); + return -1; + } + + nr_entries = sec->len / entry->size; + + for (idx = 0; idx < nr_entries; idx++) { + alt = malloc(sizeof(*alt)); + if (!alt) { + WARN("malloc failed"); + return -1; + } + memset(alt, 0, sizeof(*alt)); + + ret = get_alt_entry(elf, entry, sec, idx, alt); + if (ret) + return ret; + + list_add_tail(&alt->list, alts); + } + } + + return 0; +} diff --git a/tools/objtool/special.h b/tools/objtool/special.h new file mode 100644 index 0000000..fad1d092 --- /dev/null +++ b/tools/objtool/special.h @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef _SPECIAL_H +#define _SPECIAL_H + +#include <stdbool.h> +#include "elf.h" + +struct special_alt { + struct list_head list; + + bool group; + bool skip_orig; + bool jump_or_nop; + + struct section *orig_sec; + unsigned long orig_off; + + struct section *new_sec; + unsigned long new_off; + + unsigned int orig_len, new_len; /* group only */ +}; + +int special_get_alts(struct elf *elf, struct list_head *alts); + +#endif /* _SPECIAL_H */ diff --git a/tools/objtool/warn.h b/tools/objtool/warn.h new file mode 100644 index 0000000..ac7e075 --- /dev/null +++ b/tools/objtool/warn.h @@ -0,0 +1,60 @@ +/* + * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef _WARN_H +#define _WARN_H + +extern const char *objname; + +static inline char *offstr(struct section *sec, unsigned long offset) +{ + struct symbol *func; + char *name, *str; + unsigned long name_off; + + func = find_containing_func(sec, offset); + if (func) { + name = func->name; + name_off = offset - func->offset; + } else { + name = sec->name; + name_off = offset; + } + + str = malloc(strlen(name) + 20); + + if (func) + sprintf(str, "%s()+0x%lx", name, name_off); + else + sprintf(str, "%s+0x%lx", name, name_off); + + return str; +} + +#define WARN(format, ...) \ + fprintf(stderr, \ + "%s: warning: objtool: " format "\n", \ + objname, ##__VA_ARGS__) + +#define WARN_FUNC(format, sec, offset, ...) \ +({ \ + char *_str = offstr(sec, offset); \ + WARN("%s: " format, _str, ##__VA_ARGS__); \ + free(_str); \ +}) + +#endif /* _WARN_H */ |
