diff options
33 files changed, 1118 insertions, 456 deletions
@@ -796,6 +796,10 @@ quiet_cmd_vmlinux_version = GEN .version quiet_cmd_sysmap = SYSMAP cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap +# Sort exception table at build time +quiet_cmd_sortextable = SORTEX + cmd_sortextable = $(objtree)/scripts/sortextable + # Link of vmlinux # If CONFIG_KALLSYMS is set .version is already updated # Generate System.map and verify that the content is consistent @@ -808,6 +812,12 @@ define rule_vmlinux__ $(call cmd,vmlinux__) $(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd + $(if $(CONFIG_BUILDTIME_EXTABLE_SORT), \ + $(Q)$(if $($(quiet)cmd_sortextable), \ + echo ' $($(quiet)cmd_sortextable) vmlinux' &&) \ + $(cmd_sortextable) vmlinux) + + $(Q)$(if $($(quiet)cmd_sysmap), \ echo ' $($(quiet)cmd_sysmap) System.map' &&) \ $(cmd_sysmap) $@ System.map; \ diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index f5e1212..85aad03 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -30,6 +30,7 @@ config MIPS select HAVE_MEMBLOCK_NODE_MAP select ARCH_DISCARD_MEMBLOCK select GENERIC_SMP_IDLE_THREAD + select BUILDTIME_EXTABLE_SORT menu "Machine selection" diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7b383d8..21ea6d2 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -83,6 +83,7 @@ config X86 select DCACHE_WORD_ACCESS select GENERIC_SMP_IDLE_THREAD select HAVE_ARCH_SECCOMP_FILTER + select BUILDTIME_EXTABLE_SORT config INSTRUCTION_DECODER def_bool (KPROBES || PERF_EVENTS) diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index e3e7340..20e5f7b 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -13,6 +13,7 @@ #include <asm/thread_info.h> #include <asm/segment.h> #include <asm/irqflags.h> +#include <asm/asm.h> #include <linux/linkage.h> #include <linux/err.h> @@ -146,9 +147,7 @@ ENTRY(ia32_sysenter_target) /* no need to do an access_ok check here because rbp has been 32bit zero extended */ 1: movl (%rbp),%ebp - .section __ex_table,"a" - .quad 1b,ia32_badarg - .previous + _ASM_EXTABLE(1b,ia32_badarg) orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET) testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) CFI_REMEMBER_STATE @@ -303,9 +302,7 @@ ENTRY(ia32_cstar_target) 32bit zero extended */ /* hardware stack frame is complete now */ 1: movl (%r8),%r9d - .section __ex_table,"a" - .quad 1b,ia32_badarg - .previous + _ASM_EXTABLE(1b,ia32_badarg) orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET) testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET) CFI_REMEMBER_STATE diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h index 9412d65..1c2d247 100644 --- a/arch/x86/include/asm/asm.h +++ b/arch/x86/include/asm/asm.h @@ -4,11 +4,9 @@ #ifdef __ASSEMBLY__ # define __ASM_FORM(x) x # define __ASM_FORM_COMMA(x) x, -# define __ASM_EX_SEC .section __ex_table, "a" #else # define __ASM_FORM(x) " " #x " " # define __ASM_FORM_COMMA(x) " " #x "," -# define __ASM_EX_SEC " .section __ex_table,\"a\"\n" #endif #ifdef CONFIG_X86_32 @@ -42,17 +40,33 @@ /* Exception table entry */ #ifdef __ASSEMBLY__ -# define _ASM_EXTABLE(from,to) \ - __ASM_EX_SEC ; \ - _ASM_ALIGN ; \ - _ASM_PTR from , to ; \ - .previous +# define _ASM_EXTABLE(from,to) \ + .pushsection "__ex_table","a" ; \ + .balign 8 ; \ + .long (from) - . ; \ + .long (to) - . ; \ + .popsection + +# define _ASM_EXTABLE_EX(from,to) \ + .pushsection "__ex_table","a" ; \ + .balign 8 ; \ + .long (from) - . ; \ + .long (to) - . + 0x7ffffff0 ; \ + .popsection #else -# define _ASM_EXTABLE(from,to) \ - __ASM_EX_SEC \ - _ASM_ALIGN "\n" \ - _ASM_PTR #from "," #to "\n" \ - " .previous\n" +# define _ASM_EXTABLE(from,to) \ + " .pushsection \"__ex_table\",\"a\"\n" \ + " .balign 8\n" \ + " .long (" #from ") - .\n" \ + " .long (" #to ") - .\n" \ + " .popsection\n" + +# define _ASM_EXTABLE_EX(from,to) \ + " .pushsection \"__ex_table\",\"a\"\n" \ + " .balign 8\n" \ + " .long (" #from ") - .\n" \ + " .long (" #to ") - . + 0x7ffffff0\n" \ + " .popsection\n" #endif #endif /* _ASM_X86_ASM_H */ diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index e216ba0..e5b97be 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -27,6 +27,7 @@ #include <asm/desc.h> #include <asm/mtrr.h> #include <asm/msr-index.h> +#include <asm/asm.h> #define KVM_MAX_VCPUS 254 #define KVM_SOFT_MAX_VCPUS 160 @@ -921,9 +922,7 @@ extern bool kvm_rebooting; __ASM_SIZE(push) " $666b \n\t" \ "call kvm_spurious_fault \n\t" \ ".popsection \n\t" \ - ".pushsection __ex_table, \"a\" \n\t" \ - _ASM_PTR " 666b, 667b \n\t" \ - ".popsection" + _ASM_EXTABLE(666b, 667b) #define __kvm_handle_fault_on_reboot(insn) \ ____kvm_handle_fault_on_reboot(insn, "") diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h index 95203d4..084ef95 100644 --- a/arch/x86/include/asm/msr.h +++ b/arch/x86/include/asm/msr.h @@ -169,14 +169,7 @@ static inline int wrmsr_safe(unsigned msr, unsigned low, unsigned high) return native_write_msr_safe(msr, low, high); } -/* - * rdmsr with exception handling. - * - * Please note that the exception handling works only after we've - * switched to the "smart" #GP handler in trap_init() which knows about - * exception tables - using this macro earlier than that causes machine - * hangs on boxes which do not implement the @msr in the first argument. - */ +/* rdmsr with exception handling */ #define rdmsr_safe(msr, p1, p2) \ ({ \ int __err; \ diff --git a/arch/x86/include/asm/nops.h b/arch/x86/include/asm/nops.h index 405b4032..aff2b33 100644 --- a/arch/x86/include/asm/nops.h +++ b/arch/x86/include/asm/nops.h @@ -87,7 +87,11 @@ #define P6_NOP8 0x0f,0x1f,0x84,0x00,0,0,0,0 #define P6_NOP5_ATOMIC P6_NOP5 +#ifdef __ASSEMBLY__ +#define _ASM_MK_NOP(x) .byte x +#else #define _ASM_MK_NOP(x) ".byte " __stringify(x) "\n" +#endif #if defined(CONFIG_MK7) #define ASM_NOP1 _ASM_MK_NOP(K7_NOP1) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index aa0f913..6cbbabf 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -1023,10 +1023,8 @@ extern void default_banner(void); call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs) \ ) -#define GET_CR2_INTO_RCX \ - call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2); \ - movq %rax, %rcx; \ - xorq %rax, %rax; +#define GET_CR2_INTO_RAX \ + call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2) #define PARAVIRT_ADJUST_EXCEPTION_FRAME \ PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_adjust_exception_frame), \ diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index 1654662..c48a950 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -205,13 +205,15 @@ #define IDT_ENTRIES 256 #define NUM_EXCEPTION_VECTORS 32 +/* Bitmask of exception vectors which push an error code on the stack */ +#define EXCEPTION_ERRCODE_MASK 0x00027d00 #define GDT_SIZE (GDT_ENTRIES * 8) #define GDT_ENTRY_TLS_ENTRIES 3 #define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8) #ifdef __KERNEL__ #ifndef __ASSEMBLY__ -extern const char early_idt_handlers[NUM_EXCEPTION_VECTORS][10]; +extern const char early_idt_handlers[NUM_EXCEPTION_VECTORS][2+2+5]; /* * Load a segment. Fall back on loading the zero diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index e054459..851fe0d 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -79,11 +79,12 @@ #define access_ok(type, addr, size) (likely(__range_not_ok(addr, size) == 0)) /* - * The exception table consists of pairs of addresses: the first is the - * address of an instruction that is allowed to fault, and the second is - * the address at which the program should continue. No registers are - * modified, so it is entirely up to the continuation code to figure out - * what to do. + * The exception table consists of pairs of addresses relative to the + * exception table enty itself: the first is the address of an + * instruction that is allowed to fault, and the second is the address + * at which the program should continue. No registers are modified, + * so it is entirely up to the continuation code to figure out what to + * do. * * All the routines below use bits of fixup code that are out of line * with the main instruction path. This means when everything is well, @@ -92,10 +93,14 @@ */ struct exception_table_entry { - unsigned long insn, fixup; + int insn, fixup; }; +/* This is not the generic standard exception_table_entry format */ +#define ARCH_HAS_SORT_EXTABLE +#define ARCH_HAS_SEARCH_EXTABLE extern int fixup_exception(struct pt_regs *regs); +extern int early_fixup_exception(unsigned long *ip); /* * These are the main single-value transfer routines. They automatically @@ -202,8 +207,8 @@ extern int __get_user_bad(void); asm volatile("1: movl %%eax,0(%1)\n" \ "2: movl %%edx,4(%1)\n" \ "3:\n" \ - _ASM_EXTABLE(1b, 2b - 1b) \ - _ASM_EXTABLE(2b, 3b - 2b) \ + _ASM_EXTABLE_EX(1b, 2b) \ + _ASM_EXTABLE_EX(2b, 3b) \ : : "A" (x), "r" (addr)) #define __put_user_x8(x, ptr, __ret_pu) \ @@ -408,7 +413,7 @@ do { \ #define __get_user_asm_ex(x, addr, itype, rtype, ltype) \ asm volatile("1: mov"itype" %1,%"rtype"0\n" \ "2:\n" \ - _ASM_EXTABLE(1b, 2b - 1b) \ + _ASM_EXTABLE_EX(1b, 2b) \ : ltype(x) : "m" (__m(addr))) #define __put_user_nocheck(x, ptr, size) \ @@ -450,7 +455,7 @@ struct __large_struct { unsigned long buf[100]; }; #define __put_user_asm_ex(x, addr, itype, rtype, ltype) \ asm volatile("1: mov"itype" %"rtype"0,%1\n" \ "2:\n" \ - _ASM_EXTABLE(1b, 2b - 1b) \ + _ASM_EXTABLE_EX(1b, 2b) \ : : ltype(x), "m" (__m(addr))) /* diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index c6ce245..8a1b6f9 100644 --- a/arch/x86/include/asm/xsave.h +++ b/arch/x86/include/asm/xsave.h @@ -80,10 +80,7 @@ static inline int xsave_user(struct xsave_struct __user *buf) "3: movl $-1,%[err]\n" " jmp 2b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - _ASM_ALIGN "\n" - _ASM_PTR "1b,3b\n" - ".previous" + _ASM_EXTABLE(1b,3b) : [err] "=r" (err) : "D" (buf), "a" (-1), "d" (-1), "0" (0) : "memory"); @@ -106,10 +103,7 @@ static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask) "3: movl $-1,%[err]\n" " jmp 2b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - _ASM_ALIGN "\n" - _ASM_PTR "1b,3b\n" - ".previous" + _ASM_EXTABLE(1b,3b) : [err] "=r" (err) : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0) : "memory"); /* memory required? */ diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index 7b784f4..01ccf9b 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -56,6 +56,7 @@ #include <asm/irq_vectors.h> #include <asm/cpufeature.h> #include <asm/alternative-asm.h> +#include <asm/asm.h> /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ #include <linux/elf-em.h> @@ -151,10 +152,8 @@ .pushsection .fixup, "ax" 99: movl $0, (%esp) jmp 98b -.section __ex_table, "a" - .align 4 - .long 98b, 99b .popsection + _ASM_EXTABLE(98b,99b) .endm .macro PTGS_TO_GS @@ -164,10 +163,8 @@ .pushsection .fixup, "ax" 99: movl $0, PT_GS(%esp) jmp 98b -.section __ex_table, "a" - .align 4 - .long 98b, 99b .popsection + _ASM_EXTABLE(98b,99b) .endm .macro GS_TO_REG reg @@ -249,12 +246,10 @@ jmp 2b 6: movl $0, (%esp) jmp 3b -.section __ex_table, "a" - .align 4 - .long 1b, 4b - .long 2b, 5b - .long 3b, 6b .popsection + _ASM_EXTABLE(1b,4b) + _ASM_EXTABLE(2b,5b) + _ASM_EXTABLE(3b,6b) POP_GS_EX .endm @@ -415,10 +410,7 @@ sysenter_past_esp: jae syscall_fault 1: movl (%ebp),%ebp movl %ebp,PT_EBP(%esp) -.section __ex_table,"a" - .align 4 - .long 1b,syscall_fault -.previous + _ASM_EXTABLE(1b,syscall_fault) GET_THREAD_INFO(%ebp) @@ -485,10 +477,8 @@ sysexit_audit: .pushsection .fixup,"ax" 2: movl $0,PT_FS(%esp) jmp 1b -.section __ex_table,"a" - .align 4 - .long 1b,2b .popsection + _ASM_EXTABLE(1b,2b) PTGS_TO_GS_EX ENDPROC(ia32_sysenter_target) @@ -543,10 +533,7 @@ ENTRY(iret_exc) pushl $do_iret_error jmp error_code .previous -.section __ex_table,"a" - .align 4 - .long irq_return,iret_exc -.previous + _ASM_EXTABLE(irq_return,iret_exc) CFI_RESTORE_STATE ldt_ss: @@ -901,10 +888,7 @@ END(device_not_available) #ifdef CONFIG_PARAVIRT ENTRY(native_iret) iret -.section __ex_table,"a" - .align 4 - .long native_iret, iret_exc -.previous + _ASM_EXTABLE(native_iret, iret_exc) END(native_iret) ENTRY(native_irq_enable_sysexit) @@ -1093,13 +1077,10 @@ ENTRY(xen_failsafe_callback) movl %eax,16(%esp) jmp 4b .previous -.section __ex_table,"a" - .align 4 - .long 1b,6b - .long 2b,7b - .long 3b,8b - .long 4b,9b -.previous + _ASM_EXTABLE(1b,6b) + _ASM_EXTABLE(2b,7b) + _ASM_EXTABLE(3b,8b) + _ASM_EXTABLE(4b,9b) ENDPROC(xen_failsafe_callback) BUILD_INTERRUPT3(xen_hvm_callback_vector, XEN_HVM_EVTCHN_CALLBACK, diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index cdc79b5..320852d 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -55,6 +55,7 @@ #include <asm/paravirt.h> #include <asm/ftrace.h> #include <asm/percpu.h> +#include <asm/asm.h> #include <linux/err.h> /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ @@ -900,18 +901,12 @@ restore_args: irq_return: INTERRUPT_RETURN - - .section __ex_table, "a" - .quad irq_return, bad_iret - .previous + _ASM_EXTABLE(irq_return, bad_iret) #ifdef CONFIG_PARAVIRT ENTRY(native_iret) iretq - - .section __ex_table,"a" - .quad native_iret, bad_iret - .previous + _ASM_EXTABLE(native_iret, bad_iret) #endif .section .fixup,"ax" @@ -1181,10 +1176,7 @@ gs_change: CFI_ENDPROC END(native_load_gs_index) - .section __ex_table,"a" - .align 8 - .quad gs_change,bad_gs - .previous + _ASM_EXTABLE(gs_change,bad_gs) .section .fixup,"ax" /* running with kernelgs */ bad_gs: diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index ce0be7c..463c979 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -21,6 +21,7 @@ #include <asm/msr-index.h> #include <asm/cpufeature.h> #include <asm/percpu.h> +#include <asm/nops.h> /* Physical address */ #define pa(X) ((X) - __PAGE_OFFSET) @@ -363,28 +364,23 @@ default_entry: pushl $0 popfl -#ifdef CONFIG_SMP - cmpb $0, ready - jnz checkCPUtype -#endif /* CONFIG_SMP */ - /* * start system 32-bit setup. We need to re-do some of the things done * in 16-bit mode for the "real" operations. */ - call setup_idt - -checkCPUtype: - - movl $-1,X86_CPUID # -1 for no CPUID initially - + movl setup_once_ref,%eax + andl %eax,%eax + jz 1f # Did we do this already? + call *%eax +1: + /* check if it is 486 or 386. */ /* * XXX - this does a lot of unnecessary setup. Alignment checks don't * apply at our cpl of 0 and the stack ought to be aligned already, and * we don't need to preserve eflags. */ - + movl $-1,X86_CPUID # -1 for no CPUID initially movb $3,X86 # at least 386 pushfl # push EFLAGS popl %eax # get EFLAGS @@ -450,21 +446,6 @@ is386: movl $2,%ecx # set MP movl $(__KERNEL_PERCPU), %eax movl %eax,%fs # set this cpu's percpu -#ifdef CONFIG_CC_STACKPROTECTOR - /* - * The linker can't handle this by relocation. Manually set - * base address in stack canary segment descriptor. - */ - cmpb $0,ready - jne 1f - movl $gdt_page,%eax - movl $stack_canary,%ecx - movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax) - shrl $16, %ecx - movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax) - movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax) -1: -#endif movl $(__KERNEL_STACK_CANARY),%eax movl %eax,%gs @@ -473,7 +454,6 @@ is386: movl $2,%ecx # set MP cld # gcc2 wants the direction flag cleared at all times pushl $0 # fake return address for unwinder - movb $1, ready jmp *(initial_code) /* @@ -495,81 +475,122 @@ check_x87: .byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */ ret + +#include "verify_cpu.S" + /* - * setup_idt + * setup_once * - * sets up a idt with 256 entries pointing to - * ignore_int, interrupt gates. It doesn't actually load - * idt - that can be done only after paging has been enabled - * and the kernel moved to PAGE_OFFSET. Interrupts - * are enabled elsewhere, when we can be relatively - * sure everything is ok. + * The setup work we only want to run on the BSP. * * Warning: %esi is live across this function. */ -setup_idt: - lea ignore_int,%edx - movl $(__KERNEL_CS << 16),%eax - movw %dx,%ax /* selector = 0x0010 = cs */ - movw $0x8E00,%dx /* interrupt gate - dpl=0, present */ +__INIT +setup_once: + /* + * Set up a idt with 256 entries pointing to ignore_int, + * interrupt gates. It doesn't actually load idt - that needs + * to be done on each CPU. Interrupts are enabled elsewhere, + * when we can be relatively sure everything is ok. + */ - lea idt_table,%edi - mov $256,%ecx -rp_sidt: + movl $idt_table,%edi + movl $early_idt_handlers,%eax + movl $NUM_EXCEPTION_VECTORS,%ecx +1: movl %eax,(%edi) - movl %edx,4(%edi) + movl %eax,4(%edi) + /* interrupt gate, dpl=0, present */ + movl $(0x8E000000 + __KERNEL_CS),2(%edi) + addl $9,%eax addl $8,%edi - dec %ecx - jne rp_sidt + loop 1b -.macro set_early_handler handler,trapno - lea \handler,%edx + movl $256 - NUM_EXCEPTION_VECTORS,%ecx + movl $ignore_int,%edx movl $(__KERNEL_CS << 16),%eax - movw %dx,%ax + movw %dx,%ax /* selector = 0x0010 = cs */ movw $0x8E00,%dx /* interrupt gate - dpl=0, present */ - lea idt_table,%edi - movl %eax,8*\trapno(%edi) - movl %edx,8*\trapno+4(%edi) -.endm +2: + movl %eax,(%edi) + movl %edx,4(%edi) + addl $8,%edi + loop 2b - set_early_handler handler=early_divide_err,trapno=0 - set_early_handler handler=early_illegal_opcode,trapno=6 - set_early_handler handler=early_protection_fault,trapno=13 - set_early_handler handler=early_page_fault,trapno=14 +#ifdef CONFIG_CC_STACKPROTECTOR + /* + * Configure the stack canary. The linker can't handle this by + * relocation. Manually set base address in stack canary + * segment descriptor. + */ + movl $gdt_page,%eax + movl $stack_canary,%ecx + movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax) + shrl $16, %ecx + movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax) + movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax) +#endif + andl $0,setup_once_ref /* Once is enough, thanks */ ret -early_divide_err: - xor %edx,%edx - pushl $0 /* fake errcode */ - jmp early_fault +ENTRY(early_idt_handlers) + # 36(%esp) %eflags + # 32(%esp) %cs + # 28(%esp) %eip + # 24(%rsp) error code + i = 0 + .rept NUM_EXCEPTION_VECTORS + .if (EXCEPTION_ERRCODE_MASK >> i) & 1 + ASM_NOP2 + .else + pushl $0 # Dummy error code, to make stack frame uniform + .endif + pushl $i # 20(%esp) Vector number + jmp early_idt_handler + i = i + 1 + .endr +ENDPROC(early_idt_handlers) + + /* This is global to keep gas from relaxing the jumps */ +ENTRY(early_idt_handler) + cld + cmpl $2,%ss:early_recursion_flag + je hlt_loop + incl %ss:early_recursion_flag -early_illegal_opcode: - movl $6,%edx - pushl $0 /* fake errcode */ - jmp early_fault + push %eax # 16(%esp) + push %ecx # 12(%esp) + push %edx # 8(%esp) + push %ds # 4(%esp) + push %es # 0(%esp) + movl $(__KERNEL_DS),%eax + movl %eax,%ds + movl %eax,%es -early_protection_fault: - movl $13,%edx - jmp early_fault + cmpl $(__KERNEL_CS),32(%esp) + jne 10f -early_page_fault: - movl $14,%edx - jmp early_fault + leal 28(%esp),%eax # Pointer to %eip + call early_fixup_exception + andl %eax,%eax + jnz ex_entry /* found an exception entry */ -early_fault: - cld +10: #ifdef CONFIG_PRINTK - pusha - movl $(__KERNEL_DS),%eax - movl %eax,%ds - movl %eax,%es - cmpl $2,early_recursion_flag - je hlt_loop - incl early_recursion_flag + xorl %eax,%eax + movw %ax,2(%esp) /* clean up the segment values on some cpus */ + movw %ax,6(%esp) + movw %ax,34(%esp) + leal 40(%esp),%eax + pushl %eax /* %esp before the exception */ + pushl %ebx + pushl %ebp + pushl %esi + pushl %edi movl %cr2,%eax pushl %eax - pushl %edx /* trapno */ + pushl (20+6*4)(%esp) /* trapno */ pushl $fault_msg call printk #endif @@ -578,6 +599,17 @@ hlt_loop: hlt jmp hlt_loop +ex_entry: + pop %es + pop %ds + pop %edx + pop %ecx + pop %eax + addl $8,%esp /* drop vector number and error code */ + decl %ss:early_recursion_flag + iret +ENDPROC(early_idt_handler) + /* This is the default interrupt "handler" :-) */ ALIGN ignore_int: @@ -611,13 +643,18 @@ ignore_int: popl %eax #endif iret +ENDPROC(ignore_int) +__INITDATA + .align 4 +early_recursion_flag: + .long 0 -#include "verify_cpu.S" - - __REFDATA -.align 4 +__REFDATA + .align 4 ENTRY(initial_code) .long i386_start_kernel +ENTRY(setup_once_ref) + .long setup_once /* * BSS section @@ -670,22 +707,19 @@ ENTRY(initial_page_table) ENTRY(stack_start) .long init_thread_union+THREAD_SIZE -early_recursion_flag: - .long 0 - -ready: .byte 0 - +__INITRODATA int_msg: .asciz "Unknown interrupt or fault at: %p %p %p\n" fault_msg: /* fault info: */ .ascii "BUG: Int %d: CR2 %p\n" -/* pusha regs: */ - .ascii " EDI %p ESI %p EBP %p ESP %p\n" - .ascii " EBX %p EDX %p ECX %p EAX %p\n" +/* regs pushed in early_idt_handler: */ + .ascii " EDI %p ESI %p EBP %p EBX %p\n" + .ascii " ESP %p ES %p DS %p\n" + .ascii " EDX %p ECX %p EAX %p\n" /* fault frame: */ - .ascii " err %p EIP %p CS %p flg %p\n" + .ascii " vec %p err %p EIP %p CS %p flg %p\n" .ascii "Stack: %p %p %p %p %p %p %p %p\n" .ascii " %p %p %p %p %p %p %p %p\n" .asciz " %p %p %p %p %p %p %p %p\n" @@ -699,6 +733,7 @@ fault_msg: * segment size, and 32-bit linear address value: */ + .data .globl boot_gdt_descr .globl idt_descr diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 40f4eb3..7a40f24 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -19,12 +19,15 @@ #include <asm/cache.h> #include <asm/processor-flags.h> #include <asm/percpu.h> +#include <asm/nops.h> #ifdef CONFIG_PARAVIRT #include <asm/asm-offsets.h> #include <asm/paravirt.h> +#define GET_CR2_INTO(reg) GET_CR2_INTO_RAX ; movq %rax, reg #else -#define GET_CR2_INTO_RCX movq %cr2, %rcx +#define GET_CR2_INTO(reg) movq %cr2, reg +#define INTERRUPT_RETURN iretq #endif /* we are not able to switch in one step to the final KERNEL ADDRESS SPACE @@ -270,36 +273,56 @@ bad_address: jmp bad_address .section ".init.text","ax" -#ifdef CONFIG_EARLY_PRINTK .globl early_idt_handlers early_idt_handlers: + # 104(%rsp) %rflags + # 96(%rsp) %cs + # 88(%rsp) %rip + # 80(%rsp) error code i = 0 .rept NUM_EXCEPTION_VECTORS - movl $i, %esi + .if (EXCEPTION_ERRCODE_MASK >> i) & 1 + ASM_NOP2 + .else + pushq $0 # Dummy error code, to make stack frame uniform + .endif + pushq $i # 72(%rsp) Vector number jmp early_idt_handler i = i + 1 .endr -#endif ENTRY(early_idt_handler) -#ifdef CONFIG_EARLY_PRINTK + cld + cmpl $2,early_recursion_flag(%rip) jz 1f incl early_recursion_flag(%rip) - GET_CR2_INTO_RCX - movq %rcx,%r9 - xorl %r8d,%r8d # zero for error code - movl %esi,%ecx # get vector number - # Test %ecx against mask of vectors that push error code. - cmpl $31,%ecx - ja 0f - movl $1,%eax - salq %cl,%rax - testl $0x27d00,%eax - je 0f - popq %r8 # get error code -0: movq 0(%rsp),%rcx # get ip - movq 8(%rsp),%rdx # get cs + + pushq %rax # 64(%rsp) + pushq %rcx # 56(%rsp) + pushq %rdx # 48(%rsp) + pushq %rsi # 40(%rsp) + pushq %rdi # 32(%rsp) + pushq %r8 # 24(%rsp) + pushq %r9 # 16(%rsp) + pushq %r10 # 8(%rsp) + pushq %r11 # 0(%rsp) + + cmpl $__KERNEL_CS,96(%rsp) + jne 10f + + leaq 88(%rsp),%rdi # Pointer to %rip + call early_fixup_exception + andl %eax,%eax + jnz 20f # Found an exception entry + +10: +#ifdef CONFIG_EARLY_PRINTK + GET_CR2_INTO(%r9) # can clobber any volatile register if pv + movl 80(%rsp),%r8d # error code + movl 72(%rsp),%esi # vector number + movl 96(%rsp),%edx # %cs + movq 88(%rsp),%rcx # %rip xorl %eax,%eax leaq early_idt_msg(%rip),%rdi call early_printk @@ -308,17 +331,32 @@ ENTRY(early_idt_handler) call dump_stack #ifdef CONFIG_KALLSYMS leaq early_idt_ripmsg(%rip),%rdi - movq 0(%rsp),%rsi # get rip again + movq 40(%rsp),%rsi # %rip again call __print_symbol #endif #endif /* EARLY_PRINTK */ 1: hlt jmp 1b -#ifdef CONFIG_EARLY_PRINTK +20: # Exception table entry found + popq %r11 + popq %r10 + popq %r9 + popq %r8 + popq %rdi + popq %rsi + popq %rdx + popq %rcx + popq %rax + addq $16,%rsp # drop vector number and error code + decl early_recursion_flag(%rip) + INTERRUPT_RETURN + + .balign 4 early_recursion_flag: .long 0 +#ifdef CONFIG_EARLY_PRINTK early_idt_msg: .asciz "PANIC: early exception %02lx rip %lx:%lx error %lx cr2 %lx\n" early_idt_ripmsg: diff --git a/arch/x86/kernel/test_rodata.c b/arch/x86/kernel/test_rodata.c index c29e235..b79133a 100644 --- a/arch/x86/kernel/test_rodata.c +++ b/arch/x86/kernel/test_rodata.c @@ -12,6 +12,7 @@ #include <linux/module.h> #include <asm/cacheflush.h> #include <asm/sections.h> +#include <asm/asm.h> int rodata_test(void) { @@ -42,14 +43,7 @@ int rodata_test(void) ".section .fixup,\"ax\"\n" "2: jmp 1b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - " .align 16\n" -#ifdef CONFIG_X86_32 - " .long 0b,2b\n" -#else - " .quad 0b,2b\n" -#endif - ".previous" + _ASM_EXTABLE(0b,2b) : [rslt] "=r" (result) : [rodata_test] "r" (&rodata_test_data), [zero] "r" (0UL) ); diff --git a/arch/x86/lib/checksum_32.S b/arch/x86/lib/checksum_32.S index 78d16a5..2af5df3 100644 --- a/arch/x86/lib/checksum_32.S +++ b/arch/x86/lib/checksum_32.S @@ -28,6 +28,7 @@ #include <linux/linkage.h> #include <asm/dwarf2.h> #include <asm/errno.h> +#include <asm/asm.h> /* * computes a partial checksum, e.g. for TCP/UDP fragments @@ -282,15 +283,11 @@ unsigned int csum_partial_copy_generic (const char *src, char *dst, #define SRC(y...) \ 9999: y; \ - .section __ex_table, "a"; \ - .long 9999b, 6001f ; \ - .previous + _ASM_EXTABLE(9999b, 6001f) #define DST(y...) \ 9999: y; \ - .section __ex_table, "a"; \ - .long 9999b, 6002f ; \ - .previous + _ASM_EXTABLE(9999b, 6002f) #ifndef CONFIG_X86_USE_PPRO_CHECKSUM diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S index 0248402..5b2995f 100644 --- a/arch/x86/lib/copy_user_64.S +++ b/arch/x86/lib/copy_user_64.S @@ -16,6 +16,7 @@ #include <asm/thread_info.h> #include <asm/cpufeature.h> #include <asm/alternative-asm.h> +#include <asm/asm.h> /* * By placing feature2 after feature1 in altinstructions section, we logically @@ -63,11 +64,8 @@ jmp copy_user_handle_tail .previous - .section __ex_table,"a" - .align 8 - .quad 100b,103b - .quad 101b,103b - .previous + _ASM_EXTABLE(100b,103b) + _ASM_EXTABLE(101b,103b) #endif .endm @@ -191,29 +189,26 @@ ENTRY(copy_user_generic_unrolled) 60: jmp copy_user_handle_tail /* ecx is zerorest also */ .previous - .section __ex_table,"a" - .align 8 - .quad 1b,30b - .quad 2b,30b - .quad 3b,30b - .quad 4b,30b - .quad 5b,30b - .quad 6b,30b - .quad 7b,30b - .quad 8b,30b - .quad 9b,30b - .quad 10b,30b - .quad 11b,30b - .quad 12b,30b - .quad 13b,30b - .quad 14b,30b - .quad 15b,30b - .quad 16b,30b - .quad 18b,40b - .quad 19b,40b - .quad 21b,50b - .quad 22b,50b - .previous + _ASM_EXTABLE(1b,30b) + _ASM_EXTABLE(2b,30b) + _ASM_EXTABLE(3b,30b) + _ASM_EXTABLE(4b,30b) + _ASM_EXTABLE(5b,30b) + _ASM_EXTABLE(6b,30b) + _ASM_EXTABLE(7b,30b) + _ASM_EXTABLE(8b,30b) + _ASM_EXTABLE(9b,30b) + _ASM_EXTABLE(10b,30b) + _ASM_EXTABLE(11b,30b) + _ASM_EXTABLE(12b,30b) + _ASM_EXTABLE(13b,30b) + _ASM_EXTABLE(14b,30b) + _ASM_EXTABLE(15b,30b) + _ASM_EXTABLE(16b,30b) + _ASM_EXTABLE(18b,40b) + _ASM_EXTABLE(19b,40b) + _ASM_EXTABLE(21b,50b) + _ASM_EXTABLE(22b,50b) CFI_ENDPROC ENDPROC(copy_user_generic_unrolled) @@ -259,11 +254,8 @@ ENTRY(copy_user_generic_string) jmp copy_user_handle_tail .previous - .section __ex_table,"a" - .align 8 - .quad 1b,11b - .quad 3b,12b - .previous + _ASM_EXTABLE(1b,11b) + _ASM_EXTABLE(3b,12b) CFI_ENDPROC ENDPROC(copy_user_generic_string) @@ -294,9 +286,6 @@ ENTRY(copy_user_enhanced_fast_string) jmp copy_user_handle_tail .previous - .section __ex_table,"a" - .align 8 - .quad 1b,12b - .previous + _ASM_EXTABLE(1b,12b) CFI_ENDPROC ENDPROC(copy_user_enhanced_fast_string) diff --git a/arch/x86/lib/copy_user_nocache_64.S b/arch/x86/lib/copy_user_nocache_64.S index cb0c112..cacddc7 100644 --- a/arch/x86/lib/copy_user_nocache_64.S +++ b/arch/x86/lib/copy_user_nocache_64.S @@ -14,6 +14,7 @@ #include <asm/current.h> #include <asm/asm-offsets.h> #include <asm/thread_info.h> +#include <asm/asm.h> .macro ALIGN_DESTINATION #ifdef FIX_ALIGNMENT @@ -36,11 +37,8 @@ jmp copy_user_handle_tail .previous - .section __ex_table,"a" - .align 8 - .quad 100b,103b - .quad 101b,103b - .previous + _ASM_EXTABLE(100b,103b) + _ASM_EXTABLE(101b,103b) #endif .endm @@ -111,27 +109,25 @@ ENTRY(__copy_user_nocache) jmp copy_user_handle_tail .previous - .section __ex_table,"a" - .quad 1b,30b - .quad 2b,30b - .quad 3b,30b - .quad 4b,30b - .quad 5b,30b - .quad 6b,30b - .quad 7b,30b - .quad 8b,30b - .quad 9b,30b - .quad 10b,30b - .quad 11b,30b - .quad 12b,30b - .quad 13b,30b - .quad 14b,30b - .quad 15b,30b - .quad 16b,30b - .quad 18b,40b - .quad 19b,40b - .quad 21b,50b - .quad 22b,50b - .previous + _ASM_EXTABLE(1b,30b) + _ASM_EXTABLE(2b,30b) + _ASM_EXTABLE(3b,30b) + _ASM_EXTABLE(4b,30b) + _ASM_EXTABLE(5b,30b) + _ASM_EXTABLE(6b,30b) + _ASM_EXTABLE(7b,30b) + _ASM_EXTABLE(8b,30b) + _ASM_EXTABLE(9b,30b) + _ASM_EXTABLE(10b,30b) + _ASM_EXTABLE(11b,30b) + _ASM_EXTABLE(12b,30b) + _ASM_EXTABLE(13b,30b) + _ASM_EXTABLE(14b,30b) + _ASM_EXTABLE(15b,30b) + _ASM_EXTABLE(16b,30b) + _ASM_EXTABLE(18b,40b) + _ASM_EXTABLE(19b,40b) + _ASM_EXTABLE(21b,50b) + _ASM_EXTABLE(22b,50b) CFI_ENDPROC ENDPROC(__copy_user_nocache) diff --git a/arch/x86/lib/csum-copy_64.S b/arch/x86/lib/csum-copy_64.S index fb903b7..2419d5f 100644 --- a/arch/x86/lib/csum-copy_64.S +++ b/arch/x86/lib/csum-copy_64.S @@ -8,6 +8,7 @@ #include <linux/linkage.h> #include <asm/dwarf2.h> #include <asm/errno.h> +#include <asm/asm.h> /* * Checksum copy with exception handling. @@ -31,26 +32,17 @@ .macro source 10: - .section __ex_table, "a" - .align 8 - .quad 10b, .Lbad_source - .previous + _ASM_EXTABLE(10b, .Lbad_source) .endm .macro dest 20: - .section __ex_table, "a" - .align 8 - .quad 20b, .Lbad_dest - .previous + _ASM_EXTABLE(20b, .Lbad_dest) .endm .macro ignore L=.Lignore 30: - .section __ex_table, "a" - .align 8 - .quad 30b, \L - .previous + _ASM_EXTABLE(30b, \L) .endm diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S index 51f1504..b33b1fb 100644 --- a/arch/x86/lib/getuser.S +++ b/arch/x86/lib/getuser.S @@ -95,10 +95,9 @@ bad_get_user: CFI_ENDPROC END(bad_get_user) -.section __ex_table,"a" - _ASM_PTR 1b,bad_get_user - _ASM_PTR 2b,bad_get_user - _ASM_PTR 3b,bad_get_user + _ASM_EXTABLE(1b,bad_get_user) + _ASM_EXTABLE(2b,bad_get_user) + _ASM_EXTABLE(3b,bad_get_user) #ifdef CONFIG_X86_64 - _ASM_PTR 4b,bad_get_user + _ASM_EXTABLE(4b,bad_get_user) #endif diff --git a/arch/x86/lib/putuser.S b/arch/x86/lib/putuser.S index 36b0d15..7f951c8 100644 --- a/arch/x86/lib/putuser.S +++ b/arch/x86/lib/putuser.S @@ -86,12 +86,10 @@ bad_put_user: EXIT END(bad_put_user) -.section __ex_table,"a" - _ASM_PTR 1b,bad_put_user - _ASM_PTR 2b,bad_put_user - _ASM_PTR 3b,bad_put_user - _ASM_PTR 4b,bad_put_user + _ASM_EXTABLE(1b,bad_put_user) + _ASM_EXTABLE(2b,bad_put_user) + _ASM_EXTABLE(3b,bad_put_user) + _ASM_EXTABLE(4b,bad_put_user) #ifdef CONFIG_X86_32 - _ASM_PTR 5b,bad_put_user + _ASM_EXTABLE(5b,bad_put_user) #endif -.previous diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c index ef2a6a5..883b216 100644 --- a/arch/x86/lib/usercopy_32.c +++ b/arch/x86/lib/usercopy_32.c @@ -13,6 +13,7 @@ #include <linux/interrupt.h> #include <asm/uaccess.h> #include <asm/mmx.h> +#include <asm/asm.h> #ifdef CONFIG_X86_INTEL_USERCOPY /* @@ -127,10 +128,7 @@ long strnlen_user(const char __user *s, long n) "3: movb $1,%%al\n" " jmp 1b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - " .align 4\n" - " .long 0b,2b\n" - ".previous" + _ASM_EXTABLE(0b,2b) :"=&r" (n), "=&D" (s), "=&a" (res), "=&c" (tmp) :"0" (n), "1" (s), "2" (0), "3" (mask) :"cc"); @@ -199,47 +197,44 @@ __copy_user_intel(void __user *to, const void *from, unsigned long size) "101: lea 0(%%eax,%0,4),%0\n" " jmp 100b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - " .align 4\n" - " .long 1b,100b\n" - " .long 2b,100b\n" - " .long 3b,100b\n" - " .long 4b,100b\n" - " .long 5b,100b\n" - " .long 6b,100b\n" - " .long 7b,100b\n" - " .long 8b,100b\n" - " .long 9b,100b\n" - " .long 10b,100b\n" - " .long 11b,100b\n" - " .long 12b,100b\n" - " .long 13b,100b\n" - " .long 14b,100b\n" - " .long 15b,100b\n" - " .long 16b,100b\n" - " .long 17b,100b\n" - " .long 18b,100b\n" - " .long 19b,100b\n" - " .long 20b,100b\n" - " .long 21b,100b\n" - " .long 22b,100b\n" - " .long 23b,100b\n" - " .long 24b,100b\n" - " .long 25b,100b\n" - " .long 26b,100b\n" - " .long 27b,100b\n" - " .long 28b,100b\n" - " .long 29b,100b\n" - " .long 30b,100b\n" - " .long 31b,100b\n" - " .long 32b,100b\n" - " .long 33b,100b\n" - " .long 34b,100b\n" - " .long 35b,100b\n" - " .long 36b,100b\n" - " .long 37b,100b\n" - " .long 99b,101b\n" - ".previous" + _ASM_EXTABLE(1b,100b) + _ASM_EXTABLE(2b,100b) + _ASM_EXTABLE(3b,100b) + _ASM_EXTABLE(4b,100b) + _ASM_EXTABLE(5b,100b) + _ASM_EXTABLE(6b,100b) + _ASM_EXTABLE(7b,100b) + _ASM_EXTABLE(8b,100b) + _ASM_EXTABLE(9b,100b) + _ASM_EXTABLE(10b,100b) + _ASM_EXTABLE(11b,100b) + _ASM_EXTABLE(12b,100b) + _ASM_EXTABLE(13b,100b) + _ASM_EXTABLE(14b,100b) + _ASM_EXTABLE(15b,100b) + _ASM_EXTABLE(16b,100b) + _ASM_EXTABLE(17b,100b) + _ASM_EXTABLE(18b,100b) + _ASM_EXTABLE(19b,100b) + _ASM_EXTABLE(20b,100b) + _ASM_EXTABLE(21b,100b) + _ASM_EXTABLE(22b,100b) + _ASM_EXTABLE(23b,100b) + _ASM_EXTABLE(24b,100b) + _ASM_EXTABLE(25b,100b) + _ASM_EXTABLE(26b,100b) + _ASM_EXTABLE(27b,100b) + _ASM_EXTABLE(28b,100b) + _ASM_EXTABLE(29b,100b) + _ASM_EXTABLE(30b,100b) + _ASM_EXTABLE(31b,100b) + _ASM_EXTABLE(32b,100b) + _ASM_EXTABLE(33b,100b) + _ASM_EXTABLE(34b,100b) + _ASM_EXTABLE(35b,100b) + _ASM_EXTABLE(36b,100b) + _ASM_EXTABLE(37b,100b) + _ASM_EXTABLE(99b,101b) : "=&c"(size), "=&D" (d0), "=&S" (d1) : "1"(to), "2"(from), "0"(size) : "eax", "edx", "memory"); @@ -312,29 +307,26 @@ __copy_user_zeroing_intel(void *to, const void __user *from, unsigned long size) " popl %0\n" " jmp 8b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - " .align 4\n" - " .long 0b,16b\n" - " .long 1b,16b\n" - " .long 2b,16b\n" - " .long 21b,16b\n" - " .long 3b,16b\n" - " .long 31b,16b\n" - " .long 4b,16b\n" - " .long 41b,16b\n" - " .long 10b,16b\n" - " .long 51b,16b\n" - " .long 11b,16b\n" - " .long 61b,16b\n" - " .long 12b,16b\n" - " .long 71b,16b\n" - " .long 13b,16b\n" - " .long 81b,16b\n" - " .long 14b,16b\n" - " .long 91b,16b\n" - " .long 6b,9b\n" - " .long 7b,16b\n" - ".previous" + _ASM_EXTABLE(0b,16b) + _ASM_EXTABLE(1b,16b) + _ASM_EXTABLE(2b,16b) + _ASM_EXTABLE(21b,16b) + _ASM_EXTABLE(3b,16b) + _ASM_EXTABLE(31b,16b) + _ASM_EXTABLE(4b,16b) + _ASM_EXTABLE(41b,16b) + _ASM_EXTABLE(10b,16b) + _ASM_EXTABLE(51b,16b) + _ASM_EXTABLE(11b,16b) + _ASM_EXTABLE(61b,16b) + _ASM_EXTABLE(12b,16b) + _ASM_EXTABLE(71b,16b) + _ASM_EXTABLE(13b,16b) + _ASM_EXTABLE(81b,16b) + _ASM_EXTABLE(14b,16b) + _ASM_EXTABLE(91b,16b) + _ASM_EXTABLE(6b,9b) + _ASM_EXTABLE(7b,16b) : "=&c"(size), "=&D" (d0), "=&S" (d1) : "1"(to), "2"(from), "0"(size) : "eax", "edx", "memory"); @@ -414,29 +406,26 @@ static unsigned long __copy_user_zeroing_intel_nocache(void *to, " popl %0\n" " jmp 8b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - " .align 4\n" - " .long 0b,16b\n" - " .long 1b,16b\n" - " .long 2b,16b\n" - " .long 21b,16b\n" - " .long 3b,16b\n" - " .long 31b,16b\n" - " .long 4b,16b\n" - " .long 41b,16b\n" - " .long 10b,16b\n" - " .long 51b,16b\n" - " .long 11b,16b\n" - " .long 61b,16b\n" - " .long 12b,16b\n" - " .long 71b,16b\n" - " .long 13b,16b\n" - " .long 81b,16b\n" - " .long 14b,16b\n" - " .long 91b,16b\n" - " .long 6b,9b\n" - " .long 7b,16b\n" - ".previous" + _ASM_EXTABLE(0b,16b) + _ASM_EXTABLE(1b,16b) + _ASM_EXTABLE(2b,16b) + _ASM_EXTABLE(21b,16b) + _ASM_EXTABLE(3b,16b) + _ASM_EXTABLE(31b,16b) + _ASM_EXTABLE(4b,16b) + _ASM_EXTABLE(41b,16b) + _ASM_EXTABLE(10b,16b) + _ASM_EXTABLE(51b,16b) + _ASM_EXTABLE(11b,16b) + _ASM_EXTABLE(61b,16b) + _ASM_EXTABLE(12b,16b) + _ASM_EXTABLE(71b,16b) + _ASM_EXTABLE(13b,16b) + _ASM_EXTABLE(81b,16b) + _ASM_EXTABLE(14b,16b) + _ASM_EXTABLE(91b,16b) + _ASM_EXTABLE(6b,9b) + _ASM_EXTABLE(7b,16b) : "=&c"(size), "=&D" (d0), "=&S" (d1) : "1"(to), "2"(from), "0"(size) : "eax", "edx", "memory"); @@ -505,29 +494,26 @@ static unsigned long __copy_user_intel_nocache(void *to, "9: lea 0(%%eax,%0,4),%0\n" "16: jmp 8b\n" ".previous\n" - ".section __ex_table,\"a\"\n" - " .align 4\n" - " .long 0b,16b\n" - " .long 1b,16b\n" - " .long 2b,16b\n" - " .long 21b,16b\n" - " .long 3b,16b\n" - " .long 31b,16b\n" - " .long 4b,16b\n" - " .long 41b,16b\n" - " .long 10b,16b\n" - " .long 51b,16b\n" - " .long 11b,16b\n" - " .long 61b,16b\n" - " .long 12b,16b\n" - " .long 71b,16b\n" - " .long 13b,16b\n" - " .long 81b,16b\n" - " .long 14b,16b\n" - " .long 91b,16b\n" - " .long 6b,9b\n" - " .long 7b,16b\n" - ".previous" + _ASM_EXTABLE(0b,16b) + _ASM_EXTABLE(1b,16b) + _ASM_EXTABLE(2b,16b) + _ASM_EXTABLE(21b,16b) + _ASM_EXTABLE(3b,16b) + _ASM_EXTABLE(31b,16b) + _ASM_EXTABLE(4b,16b) + _ASM_EXTABLE(41b,16b) + _ASM_EXTABLE(10b,16b) + _ASM_EXTABLE(51b,16b) + _ASM_EXTABLE(11b,16b) + _ASM_EXTABLE(61b,16b) + _ASM_EXTABLE(12b,16b) + _ASM_EXTABLE(71b,16b) + _ASM_EXTABLE(13b,16b) + _ASM_EXTABLE(81b,16b) + _ASM_EXTABLE(14b,16b) + _ASM_EXTABLE(91b,16b) + _ASM_EXTABLE(6b,9b) + _ASM_EXTABLE(7b,16b) : "=&c"(size), "=&D" (d0), "=&S" (d1) : "1"(to), "2"(from), "0"(size) : "eax", "edx", "memory"); @@ -574,12 +560,9 @@ do { \ "3: lea 0(%3,%0,4),%0\n" \ " jmp 2b\n" \ ".previous\n" \ - ".section __ex_table,\"a\"\n" \ - " .align 4\n" \ - " .long 4b,5b\n" \ - " .long 0b,3b\n" \ - " .long 1b,2b\n" \ - ".previous" \ + _ASM_EXTABLE(4b,5b) \ + _ASM_EXTABLE(0b,3b) \ + _ASM_EXTABLE(1b,2b) \ : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \ : "3"(size), "0"(size), "1"(to), "2"(from) \ : "memory"); \ @@ -616,12 +599,9 @@ do { \ " popl %0\n" \ " jmp 2b\n" \ ".previous\n" \ - ".section __ex_table,\"a\"\n" \ - " .align 4\n" \ - " .long 4b,5b\n" \ - " .long 0b,3b\n" \ - " .long 1b,6b\n" \ - ".previous" \ + _ASM_EXTABLE(4b,5b) \ + _ASM_EXTABLE(0b,3b) \ + _ASM_EXTABLE(1b,6b) \ : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \ : "3"(size), "0"(size), "1"(to), "2"(from) \ : "memory"); \ diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index 1fb85db..903ec1e 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -1,11 +1,23 @@ #include <linux/module.h> #include <linux/spinlock.h> +#include <linux/sort.h> #include <asm/uaccess.h> +static inline unsigned long +ex_insn_addr(const struct exception_table_entry *x) +{ + return (unsigned long)&x->insn + x->insn; +} +static inline unsigned long +ex_fixup_addr(const struct exception_table_entry *x) +{ + return (unsigned long)&x->fixup + x->fixup; +} int fixup_exception(struct pt_regs *regs) { const struct exception_table_entry *fixup; + unsigned long new_ip; #ifdef CONFIG_PNPBIOS if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs))) { @@ -23,15 +35,135 @@ int fixup_exception(struct pt_regs *regs) fixup = search_exception_tables(regs->ip); if (fixup) { - /* If fixup is less than 16, it means uaccess error */ - if (fixup->fixup < 16) { + new_ip = ex_fixup_addr(fixup); + + if (fixup->fixup - fixup->insn >= 0x7ffffff0 - 4) { + /* Special hack for uaccess_err */ current_thread_info()->uaccess_err = 1; - regs->ip += fixup->fixup; - return 1; + new_ip -= 0x7ffffff0; } - regs->ip = fixup->fixup; + regs->ip = new_ip; return 1; } return 0; } + +/* Restricted version used during very early boot */ +int __init early_fixup_exception(unsigned long *ip) +{ + const struct exception_table_entry *fixup; + unsigned long new_ip; + + fixup = search_exception_tables(*ip); + if (fixup) { + new_ip = ex_fixup_addr(fixup); + + if (fixup->fixup - fixup->insn >= 0x7ffffff0 - 4) { + /* uaccess handling not supported during early boot */ + return 0; + } + + *ip = new_ip; + return 1; + } + + return 0; +} + +/* + * Search one exception table for an entry corresponding to the + * given instruction address, and return the address of the entry, + * or NULL if none is found. + * We use a binary search, and thus we assume that the table is + * already sorted. + */ +const struct exception_table_entry * +search_extable(const struct exception_table_entry *first, + const struct exception_table_entry *last, + unsigned long value) +{ + while (first <= last) { + const struct exception_table_entry *mid; + unsigned long addr; + + mid = ((last - first) >> 1) + first; + addr = ex_insn_addr(mid); + if (addr < value) + first = mid + 1; + else if (addr > value) + last = mid - 1; + else + return mid; + } + return NULL; +} + +/* + * The exception table needs to be sorted so that the binary + * search that we use to find entries in it works properly. + * This is used both for the kernel exception table and for + * the exception tables of modules that get loaded. + * + */ +static int cmp_ex(const void *a, const void *b) +{ + const struct exception_table_entry *x = a, *y = b; + + /* + * This value will always end up fittin in an int, because on + * both i386 and x86-64 the kernel symbol-reachable address + * space is < 2 GiB. + * + * This compare is only valid after normalization. + */ + return x->insn - y->insn; +} + +void sort_extable(struct exception_table_entry *start, + struct exception_table_entry *finish) +{ + struct exception_table_entry *p; + int i; + + /* Convert all entries to being relative to the start of the section */ + i = 0; + for (p = start; p < finish; p++) { + p->insn += i; + i += 4; + p->fixup += i; + i += 4; + } + + sort(start, finish - start, sizeof(struct exception_table_entry), + cmp_ex, NULL); + + /* Denormalize all entries */ + i = 0; + for (p = start; p < finish; p++) { + p->insn -= i; + i += 4; + p->fixup -= i; + i += 4; + } +} + +#ifdef CONFIG_MODULES +/* + * If the exception table is sorted, any referring to the module init + * will be at the beginning or the end. + */ +void trim_init_extable(struct module *m) +{ + /*trim the beginning*/ + while (m->num_exentries && + within_module_init(ex_insn_addr(&m->extable[0]), m)) { + m->extable++; + m->num_exentries--; + } + /*trim the end*/ + while (m->num_exentries && + within_module_init(ex_insn_addr(&m->extable[m->num_exentries-1]), m)) + m->num_exentries--; +} +#endif /* CONFIG_MODULES */ diff --git a/arch/x86/um/checksum_32.S b/arch/x86/um/checksum_32.S index f058d2f..8d0c420 100644 --- a/arch/x86/um/checksum_32.S +++ b/arch/x86/um/checksum_32.S @@ -26,6 +26,7 @@ */ #include <asm/errno.h> +#include <asm/asm.h> /* * computes a partial checksum, e.g. for TCP/UDP fragments @@ -232,15 +233,11 @@ unsigned int csum_partial_copy_generic (const char *src, char *dst, #define SRC(y...) \ 9999: y; \ - .section __ex_table, "a"; \ - .long 9999b, 6001f ; \ - .previous + _ASM_EXTABLE(9999b, 6001f) #define DST(y...) \ 9999: y; \ - .section __ex_table, "a"; \ - .long 9999b, 6002f ; \ - .previous + _ASM_EXTABLE(9999b, 6002f) .align 4 diff --git a/arch/x86/xen/xen-asm_32.S b/arch/x86/xen/xen-asm_32.S index b040b0e..f9643fc 100644 --- a/arch/x86/xen/xen-asm_32.S +++ b/arch/x86/xen/xen-asm_32.S @@ -14,6 +14,7 @@ #include <asm/thread_info.h> #include <asm/processor-flags.h> #include <asm/segment.h> +#include <asm/asm.h> #include <xen/interface/xen.h> @@ -137,10 +138,7 @@ iret_restore_end: 1: iret xen_iret_end_crit: -.section __ex_table, "a" - .align 4 - .long 1b, iret_exc -.previous + _ASM_EXTABLE(1b, iret_exc) hyper_iret: /* put this out of line since its very rarely used */ diff --git a/init/Kconfig b/init/Kconfig index da2d2d2..a30fe08 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -27,6 +27,9 @@ config IRQ_WORK bool depends on HAVE_IRQ_WORK +config BUILDTIME_EXTABLE_SORT + bool + menu "General setup" config EXPERIMENTAL diff --git a/kernel/extable.c b/kernel/extable.c index 5339705..fe35a63 100644 --- a/kernel/extable.c +++ b/kernel/extable.c @@ -35,10 +35,16 @@ DEFINE_MUTEX(text_mutex); extern struct exception_table_entry __start___ex_table[]; extern struct exception_table_entry __stop___ex_table[]; +/* Cleared by build time tools if the table is already sorted. */ +u32 __initdata main_extable_sort_needed = 1; + /* Sort the kernel's built-in exception table */ void __init sort_main_extable(void) { - sort_extable(__start___ex_table, __stop___ex_table); + if (main_extable_sort_needed) + sort_extable(__start___ex_table, __stop___ex_table); + else + pr_notice("__ex_table already sorted, skipping sort\n"); } /* Given an address, look for it in the exception tables. */ diff --git a/scripts/.gitignore b/scripts/.gitignore index 105b21f..65f362d 100644 --- a/scripts/.gitignore +++ b/scripts/.gitignore @@ -9,3 +9,4 @@ unifdef ihex2fw recordmcount docproc +sortextable diff --git a/scripts/Makefile b/scripts/Makefile index 3626666..a55b006 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -15,6 +15,9 @@ hostprogs-$(CONFIG_LOGO) += pnmtologo hostprogs-$(CONFIG_VT) += conmakehash hostprogs-$(CONFIG_IKCONFIG) += bin2c hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount +hostprogs-$(CONFIG_BUILDTIME_EXTABLE_SORT) += sortextable + +HOSTCFLAGS_sortextable.o = -I$(srctree)/tools/include always := $(hostprogs-y) $(hostprogs-m) diff --git a/scripts/sortextable.c b/scripts/sortextable.c new file mode 100644 index 0000000..1ca9ceb --- /dev/null +++ b/scripts/sortextable.c @@ -0,0 +1,322 @@ +/* + * sortextable.c: Sort the kernel's exception table + * + * Copyright 2011 - 2012 Cavium, Inc. + * + * Based on code taken from recortmcount.c which is: + * + * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved. + * Licensed under the GNU General Public License, version 2 (GPLv2). + * + * Restructured to fit Linux format, as well as other updates: + * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. + */ + +/* + * Strategy: alter the vmlinux file in-place. + */ + +#include <sys/types.h> +#include <sys/mman.h> +#include <sys/stat.h> +#include <getopt.h> +#include <elf.h> +#include <fcntl.h> +#include <setjmp.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include <tools/be_byteshift.h> +#include <tools/le_byteshift.h> + +static int fd_map; /* File descriptor for file being modified. */ +static int mmap_failed; /* Boolean flag. */ +static void *ehdr_curr; /* current ElfXX_Ehdr * for resource cleanup */ +static struct stat sb; /* Remember .st_size, etc. */ +static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */ + +/* setjmp() return values */ +enum { + SJ_SETJMP = 0, /* hardwired first return */ + SJ_FAIL, + SJ_SUCCEED +}; + +/* Per-file resource cleanup when multiple files. */ +static void +cleanup(void) +{ + if (!mmap_failed) + munmap(ehdr_curr, sb.st_size); + close(fd_map); +} + +static void __attribute__((noreturn)) +fail_file(void) +{ + cleanup(); + longjmp(jmpenv, SJ_FAIL); +} + +static void __attribute__((noreturn)) +succeed_file(void) +{ + cleanup(); + longjmp(jmpenv, SJ_SUCCEED); +} + + +/* + * Get the whole file as a programming convenience in order to avoid + * malloc+lseek+read+free of many pieces. If successful, then mmap + * avoids copying unused pieces; else just read the whole file. + * Open for both read and write. + */ +static void *mmap_file(char const *fname) +{ + void *addr; + + fd_map = open(fname, O_RDWR); + if (fd_map < 0 || fstat(fd_map, &sb) < 0) { + perror(fname); + fail_file(); + } + if (!S_ISREG(sb.st_mode)) { + fprintf(stderr, "not a regular file: %s\n", fname); + fail_file(); + } + addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, + fd_map, 0); + if (addr == MAP_FAILED) { + mmap_failed = 1; + fprintf(stderr, "Could not mmap file: %s\n", fname); + fail_file(); + } + return addr; +} + +static uint64_t r8be(const uint64_t *x) +{ + return get_unaligned_be64(x); +} +static uint32_t rbe(const uint32_t *x) +{ + return get_unaligned_be32(x); +} +static uint16_t r2be(const uint16_t *x) +{ + return get_unaligned_be16(x); +} +static uint64_t r8le(const uint64_t *x) +{ + return get_unaligned_le64(x); +} +static uint32_t rle(const uint32_t *x) +{ + return get_unaligned_le32(x); +} +static uint16_t r2le(const uint16_t *x) +{ + return get_unaligned_le16(x); +} + +static void w8be(uint64_t val, uint64_t *x) +{ + put_unaligned_be64(val, x); +} +static void wbe(uint32_t val, uint32_t *x) +{ + put_unaligned_be32(val, x); +} +static void w2be(uint16_t val, uint16_t *x) +{ + put_unaligned_be16(val, x); +} +static void w8le(uint64_t val, uint64_t *x) +{ + put_unaligned_le64(val, x); +} +static void wle(uint32_t val, uint32_t *x) +{ + put_unaligned_le32(val, x); +} +static void w2le(uint16_t val, uint16_t *x) +{ + put_unaligned_le16(val, x); +} + +static uint64_t (*r8)(const uint64_t *); +static uint32_t (*r)(const uint32_t *); +static uint16_t (*r2)(const uint16_t *); +static void (*w8)(uint64_t, uint64_t *); +static void (*w)(uint32_t, uint32_t *); +static void (*w2)(uint16_t, uint16_t *); + +typedef void (*table_sort_t)(char *, int); + +/* 32 bit and 64 bit are very similar */ +#include "sortextable.h" +#define SORTEXTABLE_64 +#include "sortextable.h" + +static int compare_x86_table(const void *a, const void *b) +{ + int32_t av = (int32_t)r(a); + int32_t bv = (int32_t)r(b); + + if (av < bv) + return -1; + if (av > bv) + return 1; + return 0; +} + +static void sort_x86_table(char *extab_image, int image_size) +{ + int i; + + /* + * Do the same thing the runtime sort does, first normalize to + * being relative to the start of the section. + */ + i = 0; + while (i < image_size) { + uint32_t *loc = (uint32_t *)(extab_image + i); + w(r(loc) + i, loc); + i += 4; + } + + qsort(extab_image, image_size / 8, 8, compare_x86_table); + + /* Now denormalize. */ + i = 0; + while (i < image_size) { + uint32_t *loc = (uint32_t *)(extab_image + i); + w(r(loc) - i, loc); + i += 4; + } +} + +static void +do_file(char const *const fname) +{ + table_sort_t custom_sort; + Elf32_Ehdr *ehdr = mmap_file(fname); + + ehdr_curr = ehdr; + switch (ehdr->e_ident[EI_DATA]) { + default: + fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", + ehdr->e_ident[EI_DATA], fname); + fail_file(); + break; + case ELFDATA2LSB: + r = rle; + r2 = r2le; + r8 = r8le; + w = wle; + w2 = w2le; + w8 = w8le; + break; + case ELFDATA2MSB: + r = rbe; + r2 = r2be; + r8 = r8be; + w = wbe; + w2 = w2be; + w8 = w8be; + break; + } /* end switch */ + if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 + || r2(&ehdr->e_type) != ET_EXEC + || ehdr->e_ident[EI_VERSION] != EV_CURRENT) { + fprintf(stderr, "unrecognized ET_EXEC file %s\n", fname); + fail_file(); + } + + custom_sort = NULL; + switch (r2(&ehdr->e_machine)) { + default: + fprintf(stderr, "unrecognized e_machine %d %s\n", + r2(&ehdr->e_machine), fname); + fail_file(); + break; + case EM_386: + case EM_X86_64: + custom_sort = sort_x86_table; + break; + case EM_MIPS: + break; + } /* end switch */ + + switch (ehdr->e_ident[EI_CLASS]) { + default: + fprintf(stderr, "unrecognized ELF class %d %s\n", + ehdr->e_ident[EI_CLASS], fname); + fail_file(); + break; + case ELFCLASS32: + if (r2(&ehdr->e_ehsize) != sizeof(Elf32_Ehdr) + || r2(&ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { + fprintf(stderr, + "unrecognized ET_EXEC file: %s\n", fname); + fail_file(); + } + do32(ehdr, fname, custom_sort); + break; + case ELFCLASS64: { + Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; + if (r2(&ghdr->e_ehsize) != sizeof(Elf64_Ehdr) + || r2(&ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { + fprintf(stderr, + "unrecognized ET_EXEC file: %s\n", fname); + fail_file(); + } + do64(ghdr, fname, custom_sort); + break; + } + } /* end switch */ + + cleanup(); +} + +int +main(int argc, char *argv[]) +{ + int n_error = 0; /* gcc-4.3.0 false positive complaint */ + int i; + + if (argc < 2) { + fprintf(stderr, "usage: sortextable vmlinux...\n"); + return 0; + } + + /* Process each file in turn, allowing deep failure. */ + for (i = 1; i < argc; i++) { + char *file = argv[i]; + int const sjval = setjmp(jmpenv); + + switch (sjval) { + default: + fprintf(stderr, "internal error: %s\n", file); + exit(1); + break; + case SJ_SETJMP: /* normal sequence */ + /* Avoid problems if early cleanup() */ + fd_map = -1; + ehdr_curr = NULL; + mmap_failed = 1; + do_file(file); + break; + case SJ_FAIL: /* error in do_file or below */ + ++n_error; + break; + case SJ_SUCCEED: /* premature success */ + /* do nothing */ + break; + } /* end switch */ + } + return !!n_error; +} diff --git a/scripts/sortextable.h b/scripts/sortextable.h new file mode 100644 index 0000000..e4fd45b --- /dev/null +++ b/scripts/sortextable.h @@ -0,0 +1,191 @@ +/* + * sortextable.h + * + * Copyright 2011 - 2012 Cavium, Inc. + * + * Some of this code was taken out of recordmcount.h written by: + * + * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved. + * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. + * + * + * Licensed under the GNU General Public License, version 2 (GPLv2). + */ + +#undef extable_ent_size +#undef compare_extable +#undef do_func +#undef Elf_Addr +#undef Elf_Ehdr +#undef Elf_Shdr +#undef Elf_Rel +#undef Elf_Rela +#undef Elf_Sym +#undef ELF_R_SYM +#undef Elf_r_sym +#undef ELF_R_INFO +#undef Elf_r_info +#undef ELF_ST_BIND +#undef ELF_ST_TYPE +#undef fn_ELF_R_SYM +#undef fn_ELF_R_INFO +#undef uint_t +#undef _r +#undef _w + +#ifdef SORTEXTABLE_64 +# define extable_ent_size 16 +# define compare_extable compare_extable_64 +# define do_func do64 +# define Elf_Addr Elf64_Addr +# define Elf_Ehdr Elf64_Ehdr +# define Elf_Shdr Elf64_Shdr +# define Elf_Rel Elf64_Rel +# define Elf_Rela Elf64_Rela +# define Elf_Sym Elf64_Sym +# define ELF_R_SYM ELF64_R_SYM +# define Elf_r_sym Elf64_r_sym +# define ELF_R_INFO ELF64_R_INFO +# define Elf_r_info Elf64_r_info +# define ELF_ST_BIND ELF64_ST_BIND +# define ELF_ST_TYPE ELF64_ST_TYPE +# define fn_ELF_R_SYM fn_ELF64_R_SYM +# define fn_ELF_R_INFO fn_ELF64_R_INFO +# define uint_t uint64_t +# define _r r8 +# define _w w8 +#else +# define extable_ent_size 8 +# define compare_extable compare_extable_32 +# define do_func do32 +# define Elf_Addr Elf32_Addr +# define Elf_Ehdr Elf32_Ehdr +# define Elf_Shdr Elf32_Shdr +# define Elf_Rel Elf32_Rel +# define Elf_Rela Elf32_Rela +# define Elf_Sym Elf32_Sym +# define ELF_R_SYM ELF32_R_SYM +# define Elf_r_sym Elf32_r_sym +# define ELF_R_INFO ELF32_R_INFO +# define Elf_r_info Elf32_r_info +# define ELF_ST_BIND ELF32_ST_BIND +# define ELF_ST_TYPE ELF32_ST_TYPE +# define fn_ELF_R_SYM fn_ELF32_R_SYM +# define fn_ELF_R_INFO fn_ELF32_R_INFO +# define uint_t uint32_t +# define _r r +# define _w w +#endif + +static int compare_extable(const void *a, const void *b) +{ + Elf_Addr av = _r(a); + Elf_Addr bv = _r(b); + + if (av < bv) + return -1; + if (av > bv) + return 1; + return 0; +} + +static void +do_func(Elf_Ehdr *ehdr, char const *const fname, table_sort_t custom_sort) +{ + Elf_Shdr *shdr; + Elf_Shdr *shstrtab_sec; + Elf_Shdr *strtab_sec = NULL; + Elf_Shdr *symtab_sec = NULL; + Elf_Shdr *extab_sec = NULL; + Elf_Sym *sym; + Elf_Sym *sort_needed_sym; + Elf_Shdr *sort_needed_sec; + Elf_Rel *relocs = NULL; + int relocs_size; + uint32_t *sort_done_location; + const char *secstrtab; + const char *strtab; + char *extab_image; + int extab_index = 0; + int i; + int idx; + + shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff)); + shstrtab_sec = shdr + r2(&ehdr->e_shstrndx); + secstrtab = (const char *)ehdr + _r(&shstrtab_sec->sh_offset); + for (i = 0; i < r2(&ehdr->e_shnum); i++) { + idx = r(&shdr[i].sh_name); + if (strcmp(secstrtab + idx, "__ex_table") == 0) { + extab_sec = shdr + i; + extab_index = i; + } + if ((r(&shdr[i].sh_type) == SHT_REL || + r(&shdr[i].sh_type) == SHT_RELA) && + r(&shdr[i].sh_info) == extab_index) { + relocs = (void *)ehdr + _r(&shdr[i].sh_offset); + relocs_size = _r(&shdr[i].sh_size); + } + if (strcmp(secstrtab + idx, ".symtab") == 0) + symtab_sec = shdr + i; + if (strcmp(secstrtab + idx, ".strtab") == 0) + strtab_sec = shdr + i; + } + if (strtab_sec == NULL) { + fprintf(stderr, "no .strtab in file: %s\n", fname); + fail_file(); + } + if (symtab_sec == NULL) { + fprintf(stderr, "no .symtab in file: %s\n", fname); + fail_file(); + } + if (extab_sec == NULL) { + fprintf(stderr, "no __ex_table in file: %s\n", fname); + fail_file(); + } + strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset); + + extab_image = (void *)ehdr + _r(&extab_sec->sh_offset); + + if (custom_sort) { + custom_sort(extab_image, _r(&extab_sec->sh_size)); + } else { + int num_entries = _r(&extab_sec->sh_size) / extable_ent_size; + qsort(extab_image, num_entries, + extable_ent_size, compare_extable); + } + /* If there were relocations, we no longer need them. */ + if (relocs) + memset(relocs, 0, relocs_size); + + /* find main_extable_sort_needed */ + sort_needed_sym = NULL; + for (i = 0; i < _r(&symtab_sec->sh_size) / sizeof(Elf_Sym); i++) { + sym = (void *)ehdr + _r(&symtab_sec->sh_offset); + sym += i; + if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) + continue; + idx = r(&sym->st_name); + if (strcmp(strtab + idx, "main_extable_sort_needed") == 0) { + sort_needed_sym = sym; + break; + } + } + if (sort_needed_sym == NULL) { + fprintf(stderr, + "no main_extable_sort_needed symbol in file: %s\n", + fname); + fail_file(); + } + sort_needed_sec = &shdr[r2(&sort_needed_sym->st_shndx)]; + sort_done_location = (void *)ehdr + + _r(&sort_needed_sec->sh_offset) + + _r(&sort_needed_sym->st_value) - + _r(&sort_needed_sec->sh_addr); + +#if 1 + printf("sort done marker at %lx\n", + (unsigned long)((char *)sort_done_location - (char *)ehdr)); +#endif + /* We sorted it, clear the flag. */ + w(0, sort_done_location); +} |
