From 6fb8cc82c096fd5ccf277678639193cae07125a0 Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas@arm.com>
Date: Mon, 2 Jun 2014 11:31:06 +0100
Subject: efi: Fix compiler warnings (unused, const, type)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This patch fixes a few compiler warning in the efi code for unused
variable, discarding const qualifier and wrong pointer type:

drivers/firmware/efi/fdt.c|66 col 22| warning: unused variable ‘name’ [-Wunused-variable]
drivers/firmware/efi/efi.c|368 col 3| warning: passing argument 3 of ‘of_get_flat_dt_prop’ from incompatible pointer type [enabled by default]
drivers/firmware/efi/efi.c|368 col 8| warning: assignment discards ‘const’ qualifier from pointer target type [enabled by default]

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
---
 drivers/firmware/efi/efi.c | 6 +++---
 drivers/firmware/efi/fdt.c | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index cd36deb..eff1a2f 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -353,10 +353,10 @@ static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
 				       int depth, void *data)
 {
 	struct param_info *info = data;
-	void *prop, *dest;
-	unsigned long len;
+	const void *prop;
+	void *dest;
 	u64 val;
-	int i;
+	int i, len;
 
 	if (depth != 1 ||
 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
diff --git a/drivers/firmware/efi/fdt.c b/drivers/firmware/efi/fdt.c
index 5c6a8e8..82d7741 100644
--- a/drivers/firmware/efi/fdt.c
+++ b/drivers/firmware/efi/fdt.c
@@ -63,7 +63,7 @@ static efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
 	 */
 	prev = 0;
 	for (;;) {
-		const char *type, *name;
+		const char *type;
 		int len;
 
 		node = fdt_next_node(fdt, prev, NULL);
-- 
cgit v1.1


From 5f56e7167e6d438324fcba87018255d81e201383 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Wed, 18 Jun 2014 15:59:46 -0700
Subject: x86/vdso: Discard the __bug_table section

It serves no purpose in user code.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/2a5bebff42defd8a5e81d96f7dc00f21143c80e8.1403129369.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/vdso/vdso-layout.lds.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/vdso/vdso-layout.lds.S b/arch/x86/vdso/vdso-layout.lds.S
index 2ec72f6..c84166c 100644
--- a/arch/x86/vdso/vdso-layout.lds.S
+++ b/arch/x86/vdso/vdso-layout.lds.S
@@ -75,6 +75,7 @@ SECTIONS
 	/DISCARD/ : {
 		*(.discard)
 		*(.discard.*)
+		*(__bug_table)
 	}
 }
 
-- 
cgit v1.1


From c1979c370273fd9f7326ffa27a63b9ddb0f495f4 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Wed, 18 Jun 2014 15:59:47 -0700
Subject: x86/vdso2c: Use better macros for ELF bitness

Rather than using a separate macro for each replacement, use generic
macros.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/d953cd2e70ceee1400985d091188cdd65fba2f05.1403129369.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/vdso/vdso2c.c | 42 +++++++++++++-----------------------------
 arch/x86/vdso/vdso2c.h | 23 ++++++++++++-----------
 2 files changed, 25 insertions(+), 40 deletions(-)

diff --git a/arch/x86/vdso/vdso2c.c b/arch/x86/vdso/vdso2c.c
index 7a6bf50..7343899 100644
--- a/arch/x86/vdso/vdso2c.c
+++ b/arch/x86/vdso/vdso2c.c
@@ -83,37 +83,21 @@ extern void bad_put_le(void);
 
 #define NSYMS (sizeof(required_syms) / sizeof(required_syms[0]))
 
-#define BITS 64
-#define GOFUNC go64
-#define Elf_Ehdr Elf64_Ehdr
-#define Elf_Shdr Elf64_Shdr
-#define Elf_Phdr Elf64_Phdr
-#define Elf_Sym Elf64_Sym
-#define Elf_Dyn Elf64_Dyn
+#define BITSFUNC3(name, bits) name##bits
+#define BITSFUNC2(name, bits) BITSFUNC3(name, bits)
+#define BITSFUNC(name) BITSFUNC2(name, ELF_BITS)
+
+#define ELF_BITS_XFORM2(bits, x) Elf##bits##_##x
+#define ELF_BITS_XFORM(bits, x) ELF_BITS_XFORM2(bits, x)
+#define ELF(x) ELF_BITS_XFORM(ELF_BITS, x)
+
+#define ELF_BITS 64
 #include "vdso2c.h"
-#undef BITS
-#undef GOFUNC
-#undef Elf_Ehdr
-#undef Elf_Shdr
-#undef Elf_Phdr
-#undef Elf_Sym
-#undef Elf_Dyn
-
-#define BITS 32
-#define GOFUNC go32
-#define Elf_Ehdr Elf32_Ehdr
-#define Elf_Shdr Elf32_Shdr
-#define Elf_Phdr Elf32_Phdr
-#define Elf_Sym Elf32_Sym
-#define Elf_Dyn Elf32_Dyn
+#undef ELF_BITS
+
+#define ELF_BITS 32
 #include "vdso2c.h"
-#undef BITS
-#undef GOFUNC
-#undef Elf_Ehdr
-#undef Elf_Shdr
-#undef Elf_Phdr
-#undef Elf_Sym
-#undef Elf_Dyn
+#undef ELF_BITS
 
 static void go(void *addr, size_t len, FILE *outfile, const char *name)
 {
diff --git a/arch/x86/vdso/vdso2c.h b/arch/x86/vdso/vdso2c.h
index c6eefaf..8e185ce3 100644
--- a/arch/x86/vdso/vdso2c.h
+++ b/arch/x86/vdso/vdso2c.h
@@ -4,23 +4,24 @@
  * are built for 32-bit userspace.
  */
 
-static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
+static void BITSFUNC(go)(void *addr, size_t len,
+			 FILE *outfile, const char *name)
 {
 	int found_load = 0;
 	unsigned long load_size = -1;  /* Work around bogus warning */
 	unsigned long data_size;
-	Elf_Ehdr *hdr = (Elf_Ehdr *)addr;
+	ELF(Ehdr) *hdr = (ELF(Ehdr) *)addr;
 	int i;
 	unsigned long j;
-	Elf_Shdr *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
+	ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
 		*alt_sec = NULL;
-	Elf_Dyn *dyn = 0, *dyn_end = 0;
+	ELF(Dyn) *dyn = 0, *dyn_end = 0;
 	const char *secstrings;
 	uint64_t syms[NSYMS] = {};
 
 	uint64_t fake_sections_value = 0, fake_sections_size = 0;
 
-	Elf_Phdr *pt = (Elf_Phdr *)(addr + GET_LE(&hdr->e_phoff));
+	ELF(Phdr) *pt = (ELF(Phdr) *)(addr + GET_LE(&hdr->e_phoff));
 
 	/* Walk the segment table. */
 	for (i = 0; i < GET_LE(&hdr->e_phnum); i++) {
@@ -61,7 +62,7 @@ static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
 		GET_LE(&hdr->e_shentsize)*GET_LE(&hdr->e_shstrndx);
 	secstrings = addr + GET_LE(&secstrings_hdr->sh_offset);
 	for (i = 0; i < GET_LE(&hdr->e_shnum); i++) {
-		Elf_Shdr *sh = addr + GET_LE(&hdr->e_shoff) +
+		ELF(Shdr) *sh = addr + GET_LE(&hdr->e_shoff) +
 			GET_LE(&hdr->e_shentsize) * i;
 		if (GET_LE(&sh->sh_type) == SHT_SYMTAB)
 			symtab_hdr = sh;
@@ -82,7 +83,7 @@ static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
 	     i < GET_LE(&symtab_hdr->sh_size) / GET_LE(&symtab_hdr->sh_entsize);
 	     i++) {
 		int k;
-		Elf_Sym *sym = addr + GET_LE(&symtab_hdr->sh_offset) +
+		ELF(Sym) *sym = addr + GET_LE(&symtab_hdr->sh_offset) +
 			GET_LE(&symtab_hdr->sh_entsize) * i;
 		const char *name = addr + GET_LE(&strtab_hdr->sh_offset) +
 			GET_LE(&sym->st_name);
@@ -123,12 +124,12 @@ static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
 		fail("end_mapping must be a multiple of 4096\n");
 
 	/* Remove sections or use fakes */
-	if (fake_sections_size % sizeof(Elf_Shdr))
+	if (fake_sections_size % sizeof(ELF(Shdr)))
 		fail("vdso_fake_sections size is not a multiple of %ld\n",
-		     (long)sizeof(Elf_Shdr));
+		     (long)sizeof(ELF(Shdr)));
 	PUT_LE(&hdr->e_shoff, fake_sections_value);
-	PUT_LE(&hdr->e_shentsize, fake_sections_value ? sizeof(Elf_Shdr) : 0);
-	PUT_LE(&hdr->e_shnum, fake_sections_size / sizeof(Elf_Shdr));
+	PUT_LE(&hdr->e_shentsize, fake_sections_value ? sizeof(ELF(Shdr)) : 0);
+	PUT_LE(&hdr->e_shnum, fake_sections_size / sizeof(ELF(Shdr)));
 	PUT_LE(&hdr->e_shstrndx, SHN_UNDEF);
 
 	if (!name) {
-- 
cgit v1.1


From bfad381c0d1e19cae8461e105d8d4387dd2a14fe Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Wed, 18 Jun 2014 15:59:48 -0700
Subject: x86/vdso: Improve the fake section headers

Fully stripping the vDSO has other unfortunate side effects:

 - binutils is unable to find ELF notes without a SHT_NOTE section.

 - Even elfutils has trouble: it can find ELF notes without a section
   table at all, but if a section table is present, it won't look for
   PT_NOTE.

 - gdb wants section names to match between stripped DSOs and their
   symbols; otherwise it will corrupt symbol addresses.

We're also breaking the rules: section 0 is supposed to be SHT_NULL.

Fix these problems by building a better fake section table.  While
we're at it, we might as well let buggy Go versions keep working well
by giving the SHT_DYNSYM entry the correct size.

This is a bit unfortunate: it adds quite a bit of size to the vdso
image.

If/when binutils improves and the improved versions become widespread,
it would be worth considering dropping most of this.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/0e546a5eeaafdf1840e6ee654a55c1e727c26663.1403129369.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/vdso/Makefile                   |   4 +-
 arch/x86/vdso/vdso-fakesections.c        |  44 ++++----
 arch/x86/vdso/vdso-layout.lds.S          |  40 +++++--
 arch/x86/vdso/vdso.lds.S                 |   2 +
 arch/x86/vdso/vdso2c.c                   |  31 ++++--
 arch/x86/vdso/vdso2c.h                   | 180 +++++++++++++++++++++++++++----
 arch/x86/vdso/vdso32/vdso-fakesections.c |   1 +
 arch/x86/vdso/vdsox32.lds.S              |   2 +
 8 files changed, 237 insertions(+), 67 deletions(-)
 create mode 100644 arch/x86/vdso/vdso32/vdso-fakesections.c

diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index 3c0809a..2c1ca98 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -11,7 +11,6 @@ VDSO32-$(CONFIG_COMPAT)		:= y
 
 # files to link into the vdso
 vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o vdso-fakesections.o
-vobjs-nox32 := vdso-fakesections.o
 
 # files to link into kernel
 obj-y				+= vma.o
@@ -134,7 +133,7 @@ override obj-dirs = $(dir $(obj)) $(obj)/vdso32/
 
 targets += vdso32/vdso32.lds
 targets += vdso32/note.o vdso32/vclock_gettime.o $(vdso32.so-y:%=vdso32/%.o)
-targets += vdso32/vclock_gettime.o
+targets += vdso32/vclock_gettime.o vdso32/vdso-fakesections.o
 
 $(obj)/vdso32.o: $(vdso32-images:%=$(obj)/%)
 
@@ -155,6 +154,7 @@ $(vdso32-images:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
 $(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \
 				 $(obj)/vdso32/vdso32.lds \
 				 $(obj)/vdso32/vclock_gettime.o \
+				 $(obj)/vdso32/vdso-fakesections.o \
 				 $(obj)/vdso32/note.o \
 				 $(obj)/vdso32/%.o
 	$(call if_changed,vdso)
diff --git a/arch/x86/vdso/vdso-fakesections.c b/arch/x86/vdso/vdso-fakesections.c
index cb8a8d7..56927a7 100644
--- a/arch/x86/vdso/vdso-fakesections.c
+++ b/arch/x86/vdso/vdso-fakesections.c
@@ -2,31 +2,23 @@
  * Copyright 2014 Andy Lutomirski
  * Subject to the GNU Public License, v.2
  *
- * Hack to keep broken Go programs working.
- *
- * The Go runtime had a couple of bugs: it would read the section table to try
- * to figure out how many dynamic symbols there were (it shouldn't have looked
- * at the section table at all) and, if there were no SHT_SYNDYM section table
- * entry, it would use an uninitialized value for the number of symbols.  As a
- * workaround, we supply a minimal section table.  vdso2c will adjust the
- * in-memory image so that "vdso_fake_sections" becomes the section table.
- *
- * The bug was introduced by:
- * https://code.google.com/p/go/source/detail?r=56ea40aac72b (2012-08-31)
- * and is being addressed in the Go runtime in this issue:
- * https://code.google.com/p/go/issues/detail?id=8197
+ * String table for loadable section headers.  See vdso2c.h for why
+ * this exists.
  */
 
-#ifndef __x86_64__
-#error This hack is specific to the 64-bit vDSO
-#endif
-
-#include <linux/elf.h>
-
-extern const __visible struct elf64_shdr vdso_fake_sections[];
-const __visible struct elf64_shdr vdso_fake_sections[] = {
-	{
-		.sh_type = SHT_DYNSYM,
-		.sh_entsize = sizeof(Elf64_Sym),
-	}
-};
+const char fake_shstrtab[] __attribute__((section(".fake_shstrtab"))) =
+	".hash\0"
+	".dynsym\0"
+	".dynstr\0"
+	".gnu.version\0"
+	".gnu.version_d\0"
+	".dynamic\0"
+	".rodata\0"
+	".fake_shstrtab\0"  /* Yay, self-referential code. */
+	".note\0"
+	".data\0"
+	".altinstructions\0"
+	".altinstr_replacement\0"
+	".eh_frame_hdr\0"
+	".eh_frame\0"
+	".text";
diff --git a/arch/x86/vdso/vdso-layout.lds.S b/arch/x86/vdso/vdso-layout.lds.S
index c84166c..e4cbc21 100644
--- a/arch/x86/vdso/vdso-layout.lds.S
+++ b/arch/x86/vdso/vdso-layout.lds.S
@@ -6,6 +6,16 @@
  * This script controls its layout.
  */
 
+#if defined(BUILD_VDSO64)
+# define SHDR_SIZE 64
+#elif defined(BUILD_VDSO32) || defined(BUILD_VDSOX32)
+# define SHDR_SIZE 40
+#else
+# error unknown VDSO target
+#endif
+
+#define NUM_FAKE_SHDRS 16
+
 SECTIONS
 {
 	. = SIZEOF_HEADERS;
@@ -25,15 +35,29 @@ SECTIONS
 
 	.dynamic	: { *(.dynamic) }		:text	:dynamic
 
-	.rodata		: { *(.rodata*) }		:text
+	.rodata		: {
+		*(.rodata*)
+
+		/*
+		 * Ideally this would live in a C file, but that won't
+		 * work cleanly for x32 until we start building the x32
+		 * C code using an x32 toolchain.
+		 */
+		VDSO_FAKE_SECTION_TABLE_START = .;
+		. = . + NUM_FAKE_SHDRS * SHDR_SIZE;
+		VDSO_FAKE_SECTION_TABLE_END = .;
+	}						:text
+
+	.fake_shstrtab	: { *(.fake_shstrtab) }		:text
+
 	.data		: {
-	      *(.data*)
-	      *(.sdata*)
-	      *(.got.plt) *(.got)
-	      *(.gnu.linkonce.d.*)
-	      *(.bss*)
-	      *(.dynbss*)
-	      *(.gnu.linkonce.b.*)
+		*(.data*)
+		*(.sdata*)
+		*(.got.plt) *(.got)
+		*(.gnu.linkonce.d.*)
+		*(.bss*)
+		*(.dynbss*)
+		*(.gnu.linkonce.b.*)
 	}
 
 	.altinstructions	: { *(.altinstructions) }
diff --git a/arch/x86/vdso/vdso.lds.S b/arch/x86/vdso/vdso.lds.S
index 75e3404..6807932 100644
--- a/arch/x86/vdso/vdso.lds.S
+++ b/arch/x86/vdso/vdso.lds.S
@@ -6,6 +6,8 @@
  * the DSO.
  */
 
+#define BUILD_VDSO64
+
 #include "vdso-layout.lds.S"
 
 /*
diff --git a/arch/x86/vdso/vdso2c.c b/arch/x86/vdso/vdso2c.c
index 7343899..238dbe82 100644
--- a/arch/x86/vdso/vdso2c.c
+++ b/arch/x86/vdso/vdso2c.c
@@ -23,6 +23,8 @@ enum {
 	sym_vvar_page,
 	sym_hpet_page,
 	sym_end_mapping,
+	sym_VDSO_FAKE_SECTION_TABLE_START,
+	sym_VDSO_FAKE_SECTION_TABLE_END,
 };
 
 const int special_pages[] = {
@@ -30,15 +32,26 @@ const int special_pages[] = {
 	sym_hpet_page,
 };
 
-char const * const required_syms[] = {
-	[sym_vvar_page] = "vvar_page",
-	[sym_hpet_page] = "hpet_page",
-	[sym_end_mapping] = "end_mapping",
-	"VDSO32_NOTE_MASK",
-	"VDSO32_SYSENTER_RETURN",
-	"__kernel_vsyscall",
-	"__kernel_sigreturn",
-	"__kernel_rt_sigreturn",
+struct vdso_sym {
+	const char *name;
+	bool export;
+};
+
+struct vdso_sym required_syms[] = {
+	[sym_vvar_page] = {"vvar_page", true},
+	[sym_hpet_page] = {"hpet_page", true},
+	[sym_end_mapping] = {"end_mapping", true},
+	[sym_VDSO_FAKE_SECTION_TABLE_START] = {
+		"VDSO_FAKE_SECTION_TABLE_START", false
+	},
+	[sym_VDSO_FAKE_SECTION_TABLE_END] = {
+		"VDSO_FAKE_SECTION_TABLE_END", false
+	},
+	{"VDSO32_NOTE_MASK", true},
+	{"VDSO32_SYSENTER_RETURN", true},
+	{"__kernel_vsyscall", true},
+	{"__kernel_sigreturn", true},
+	{"__kernel_rt_sigreturn", true},
 };
 
 __attribute__((format(printf, 1, 2))) __attribute__((noreturn))
diff --git a/arch/x86/vdso/vdso2c.h b/arch/x86/vdso/vdso2c.h
index 8e185ce3..f01ed4b 100644
--- a/arch/x86/vdso/vdso2c.h
+++ b/arch/x86/vdso/vdso2c.h
@@ -4,6 +4,116 @@
  * are built for 32-bit userspace.
  */
 
+/*
+ * We're writing a section table for a few reasons:
+ *
+ * The Go runtime had a couple of bugs: it would read the section
+ * table to try to figure out how many dynamic symbols there were (it
+ * shouldn't have looked at the section table at all) and, if there
+ * were no SHT_SYNDYM section table entry, it would use an
+ * uninitialized value for the number of symbols.  An empty DYNSYM
+ * table would work, but I see no reason not to write a valid one (and
+ * keep full performance for old Go programs).  This hack is only
+ * needed on x86_64.
+ *
+ * The bug was introduced on 2012-08-31 by:
+ * https://code.google.com/p/go/source/detail?r=56ea40aac72b
+ * and was fixed on 2014-06-13 by:
+ * https://code.google.com/p/go/source/detail?r=fc1cd5e12595
+ *
+ * Binutils has issues debugging the vDSO: it reads the section table to
+ * find SHT_NOTE; it won't look at PT_NOTE for the in-memory vDSO, which
+ * would break build-id if we removed the section table.  Binutils
+ * also requires that shstrndx != 0.  See:
+ * https://sourceware.org/bugzilla/show_bug.cgi?id=17064
+ *
+ * elfutils might not look for PT_NOTE if there is a section table at
+ * all.  I don't know whether this matters for any practical purpose.
+ *
+ * For simplicity, rather than hacking up a partial section table, we
+ * just write a mostly complete one.  We omit non-dynamic symbols,
+ * though, since they're rather large.
+ *
+ * Once binutils gets fixed, we might be able to drop this for all but
+ * the 64-bit vdso, since build-id only works in kernel RPMs, and
+ * systems that update to new enough kernel RPMs will likely update
+ * binutils in sync.  build-id has never worked for home-built kernel
+ * RPMs without manual symlinking, and I suspect that no one ever does
+ * that.
+ */
+struct BITSFUNC(fake_sections)
+{
+	ELF(Shdr) *table;
+	unsigned long table_offset;
+	int count, max_count;
+
+	int in_shstrndx;
+	unsigned long shstr_offset;
+	const char *shstrtab;
+	size_t shstrtab_len;
+
+	int out_shstrndx;
+};
+
+static unsigned int BITSFUNC(find_shname)(struct BITSFUNC(fake_sections) *out,
+					  const char *name)
+{
+	const char *outname = out->shstrtab;
+	while (outname - out->shstrtab < out->shstrtab_len) {
+		if (!strcmp(name, outname))
+			return (outname - out->shstrtab) + out->shstr_offset;
+		outname += strlen(outname) + 1;
+	}
+
+	if (*name)
+		printf("Warning: could not find output name \"%s\"\n", name);
+	return out->shstr_offset + out->shstrtab_len - 1;  /* Use a null. */
+}
+
+static void BITSFUNC(init_sections)(struct BITSFUNC(fake_sections) *out)
+{
+	if (!out->in_shstrndx)
+		fail("didn't find the fake shstrndx\n");
+
+	memset(out->table, 0, out->max_count * sizeof(ELF(Shdr)));
+
+	if (out->max_count < 1)
+		fail("we need at least two fake output sections\n");
+
+	PUT_LE(&out->table[0].sh_type, SHT_NULL);
+	PUT_LE(&out->table[0].sh_name, BITSFUNC(find_shname)(out, ""));
+
+	out->count = 1;
+}
+
+static void BITSFUNC(copy_section)(struct BITSFUNC(fake_sections) *out,
+				   int in_idx, const ELF(Shdr) *in,
+				   const char *name)
+{
+	uint64_t flags = GET_LE(&in->sh_flags);
+
+	bool copy = flags & SHF_ALLOC;
+
+	if (!copy)
+		return;
+
+	if (out->count >= out->max_count)
+		fail("too many copied sections (max = %d)\n", out->max_count);
+
+	if (in_idx == out->in_shstrndx)
+		out->out_shstrndx = out->count;
+
+	out->table[out->count] = *in;
+	PUT_LE(&out->table[out->count].sh_name,
+	       BITSFUNC(find_shname)(out, name));
+
+	/* elfutils requires that a strtab have the correct type. */
+	if (!strcmp(name, ".fake_shstrtab"))
+		PUT_LE(&out->table[out->count].sh_type, SHT_STRTAB);
+
+	out->count++;
+}
+
 static void BITSFUNC(go)(void *addr, size_t len,
 			 FILE *outfile, const char *name)
 {
@@ -19,7 +129,7 @@ static void BITSFUNC(go)(void *addr, size_t len,
 	const char *secstrings;
 	uint64_t syms[NSYMS] = {};
 
-	uint64_t fake_sections_value = 0, fake_sections_size = 0;
+	struct BITSFUNC(fake_sections) fake_sections = {};
 
 	ELF(Phdr) *pt = (ELF(Phdr) *)(addr + GET_LE(&hdr->e_phoff));
 
@@ -89,23 +199,57 @@ static void BITSFUNC(go)(void *addr, size_t len,
 			GET_LE(&sym->st_name);
 
 		for (k = 0; k < NSYMS; k++) {
-			if (!strcmp(name, required_syms[k])) {
+			if (!strcmp(name, required_syms[k].name)) {
 				if (syms[k]) {
 					fail("duplicate symbol %s\n",
-					     required_syms[k]);
+					     required_syms[k].name);
 				}
 				syms[k] = GET_LE(&sym->st_value);
 			}
 		}
 
-		if (!strcmp(name, "vdso_fake_sections")) {
-			if (fake_sections_value)
-				fail("duplicate vdso_fake_sections\n");
-			fake_sections_value = GET_LE(&sym->st_value);
-			fake_sections_size = GET_LE(&sym->st_size);
+		if (!strcmp(name, "fake_shstrtab")) {
+			ELF(Shdr) *sh;
+
+			fake_sections.in_shstrndx = GET_LE(&sym->st_shndx);
+			fake_sections.shstrtab = addr + GET_LE(&sym->st_value);
+			fake_sections.shstrtab_len = GET_LE(&sym->st_size);
+			sh = addr + GET_LE(&hdr->e_shoff) +
+				GET_LE(&hdr->e_shentsize) *
+				fake_sections.in_shstrndx;
+			fake_sections.shstr_offset = GET_LE(&sym->st_value) -
+				GET_LE(&sh->sh_addr);
 		}
 	}
 
+	/* Build the output section table. */
+	if (!syms[sym_VDSO_FAKE_SECTION_TABLE_START] ||
+	    !syms[sym_VDSO_FAKE_SECTION_TABLE_END])
+		fail("couldn't find fake section table\n");
+	if ((syms[sym_VDSO_FAKE_SECTION_TABLE_END] -
+	     syms[sym_VDSO_FAKE_SECTION_TABLE_START]) % sizeof(ELF(Shdr)))
+		fail("fake section table size isn't a multiple of sizeof(Shdr)\n");
+	fake_sections.table = addr + syms[sym_VDSO_FAKE_SECTION_TABLE_START];
+	fake_sections.table_offset = syms[sym_VDSO_FAKE_SECTION_TABLE_START];
+	fake_sections.max_count = (syms[sym_VDSO_FAKE_SECTION_TABLE_END] -
+				   syms[sym_VDSO_FAKE_SECTION_TABLE_START]) /
+		sizeof(ELF(Shdr));
+
+	BITSFUNC(init_sections)(&fake_sections);
+	for (i = 0; i < GET_LE(&hdr->e_shnum); i++) {
+		ELF(Shdr) *sh = addr + GET_LE(&hdr->e_shoff) +
+			GET_LE(&hdr->e_shentsize) * i;
+		BITSFUNC(copy_section)(&fake_sections, i, sh,
+				       secstrings + GET_LE(&sh->sh_name));
+	}
+	if (!fake_sections.out_shstrndx)
+		fail("didn't generate shstrndx?!?\n");
+
+	PUT_LE(&hdr->e_shoff, fake_sections.table_offset);
+	PUT_LE(&hdr->e_shentsize, sizeof(ELF(Shdr)));
+	PUT_LE(&hdr->e_shnum, fake_sections.count);
+	PUT_LE(&hdr->e_shstrndx, fake_sections.out_shstrndx);
+
 	/* Validate mapping addresses. */
 	for (i = 0; i < sizeof(special_pages) / sizeof(special_pages[0]); i++) {
 		if (!syms[i])
@@ -113,25 +257,17 @@ static void BITSFUNC(go)(void *addr, size_t len,
 
 		if (syms[i] % 4096)
 			fail("%s must be a multiple of 4096\n",
-			     required_syms[i]);
+			     required_syms[i].name);
 		if (syms[i] < data_size)
 			fail("%s must be after the text mapping\n",
-			     required_syms[i]);
+			     required_syms[i].name);
 		if (syms[sym_end_mapping] < syms[i] + 4096)
-			fail("%s overruns end_mapping\n", required_syms[i]);
+			fail("%s overruns end_mapping\n",
+			     required_syms[i].name);
 	}
 	if (syms[sym_end_mapping] % 4096)
 		fail("end_mapping must be a multiple of 4096\n");
 
-	/* Remove sections or use fakes */
-	if (fake_sections_size % sizeof(ELF(Shdr)))
-		fail("vdso_fake_sections size is not a multiple of %ld\n",
-		     (long)sizeof(ELF(Shdr)));
-	PUT_LE(&hdr->e_shoff, fake_sections_value);
-	PUT_LE(&hdr->e_shentsize, fake_sections_value ? sizeof(ELF(Shdr)) : 0);
-	PUT_LE(&hdr->e_shnum, fake_sections_size / sizeof(ELF(Shdr)));
-	PUT_LE(&hdr->e_shstrndx, SHN_UNDEF);
-
 	if (!name) {
 		fwrite(addr, load_size, 1, outfile);
 		return;
@@ -169,9 +305,9 @@ static void BITSFUNC(go)(void *addr, size_t len,
 			(unsigned long)GET_LE(&alt_sec->sh_size));
 	}
 	for (i = 0; i < NSYMS; i++) {
-		if (syms[i])
+		if (required_syms[i].export && syms[i])
 			fprintf(outfile, "\t.sym_%s = 0x%" PRIx64 ",\n",
-				required_syms[i], syms[i]);
+				required_syms[i].name, syms[i]);
 	}
 	fprintf(outfile, "};\n");
 }
diff --git a/arch/x86/vdso/vdso32/vdso-fakesections.c b/arch/x86/vdso/vdso32/vdso-fakesections.c
new file mode 100644
index 0000000..541468e
--- /dev/null
+++ b/arch/x86/vdso/vdso32/vdso-fakesections.c
@@ -0,0 +1 @@
+#include "../vdso-fakesections.c"
diff --git a/arch/x86/vdso/vdsox32.lds.S b/arch/x86/vdso/vdsox32.lds.S
index 46b991b..697c11e 100644
--- a/arch/x86/vdso/vdsox32.lds.S
+++ b/arch/x86/vdso/vdsox32.lds.S
@@ -6,6 +6,8 @@
  * the DSO.
  */
 
+#define BUILD_VDSOX32
+
 #include "vdso-layout.lds.S"
 
 /*
-- 
cgit v1.1


From 0e3727a8839c988a3c56170bc8da76d55a16acad Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Wed, 18 Jun 2014 15:59:49 -0700
Subject: x86/vdso: Remove some redundant in-memory section headers

.data doesn't need to be separate from .rodata: they're both readonly.

.altinstructions and .altinstr_replacement aren't needed by anything
except vdso2c; strip them from the final image.

While we're at it, rather than aligning the actual executable text,
just shove some unused-at-runtime data in between real data and
text.

My vdso image is still above 4k, but I'm disinclined to try to
trim it harder for 3.16.  For future trimming, I suspect that these
sections could be moved to later in the file and dropped from
the in-memory image:

.gnu.version and .gnu.version_d   (this may lose versions in gdb)
.eh_frame                         (should be harmless)
.eh_frame_hdr                     (I'm not really sure)
.hash                             (AFAIK nothing needs this section header)

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/2e96d0c49016ea6d026a614ae645e93edd325961.1403129369.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/vdso/vdso-fakesections.c |  3 ---
 arch/x86/vdso/vdso-layout.lds.S   | 43 +++++++++++++++++++++------------------
 arch/x86/vdso/vdso2c.h            |  4 +++-
 3 files changed, 26 insertions(+), 24 deletions(-)

diff --git a/arch/x86/vdso/vdso-fakesections.c b/arch/x86/vdso/vdso-fakesections.c
index 56927a7..aa5fbfa 100644
--- a/arch/x86/vdso/vdso-fakesections.c
+++ b/arch/x86/vdso/vdso-fakesections.c
@@ -16,9 +16,6 @@ const char fake_shstrtab[] __attribute__((section(".fake_shstrtab"))) =
 	".rodata\0"
 	".fake_shstrtab\0"  /* Yay, self-referential code. */
 	".note\0"
-	".data\0"
-	".altinstructions\0"
-	".altinstr_replacement\0"
 	".eh_frame_hdr\0"
 	".eh_frame\0"
 	".text";
diff --git a/arch/x86/vdso/vdso-layout.lds.S b/arch/x86/vdso/vdso-layout.lds.S
index e4cbc21..9197544 100644
--- a/arch/x86/vdso/vdso-layout.lds.S
+++ b/arch/x86/vdso/vdso-layout.lds.S
@@ -14,7 +14,7 @@
 # error unknown VDSO target
 #endif
 
-#define NUM_FAKE_SHDRS 16
+#define NUM_FAKE_SHDRS 13
 
 SECTIONS
 {
@@ -28,15 +28,17 @@ SECTIONS
 	.gnu.version_d	: { *(.gnu.version_d) }
 	.gnu.version_r	: { *(.gnu.version_r) }
 
-	.note		: { *(.note.*) }		:text	:note
-
-	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
-	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
-
 	.dynamic	: { *(.dynamic) }		:text	:dynamic
 
 	.rodata		: {
 		*(.rodata*)
+		*(.data*)
+		*(.sdata*)
+		*(.got.plt) *(.got)
+		*(.gnu.linkonce.d.*)
+		*(.bss*)
+		*(.dynbss*)
+		*(.gnu.linkonce.b.*)
 
 		/*
 		 * Ideally this would live in a C file, but that won't
@@ -50,28 +52,29 @@ SECTIONS
 
 	.fake_shstrtab	: { *(.fake_shstrtab) }		:text
 
-	.data		: {
-		*(.data*)
-		*(.sdata*)
-		*(.got.plt) *(.got)
-		*(.gnu.linkonce.d.*)
-		*(.bss*)
-		*(.dynbss*)
-		*(.gnu.linkonce.b.*)
-	}
 
-	.altinstructions	: { *(.altinstructions) }
-	.altinstr_replacement	: { *(.altinstr_replacement) }
+	.note		: { *(.note.*) }		:text	:note
+
+	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
+	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
+
 
 	/*
-	 * Align the actual code well away from the non-instruction data.
-	 * This is the best thing for the I-cache.
+	 * Text is well-separated from actual data: there's plenty of
+	 * stuff that isn't used at runtime in between.
 	 */
-	. = ALIGN(0x100);
 
 	.text		: { *(.text*) }			:text	=0x90909090,
 
 	/*
+	 * At the end so that eu-elflint stays happy when vdso2c strips
+	 * these.  A better implementation would avoid allocating space
+	 * for these.
+	 */
+	.altinstructions	: { *(.altinstructions) }	:text
+	.altinstr_replacement	: { *(.altinstr_replacement) }	:text
+
+	/*
 	 * The remainder of the vDSO consists of special pages that are
 	 * shared between the kernel and userspace.  It needs to be at the
 	 * end so that it doesn't overlap the mapping of the actual
diff --git a/arch/x86/vdso/vdso2c.h b/arch/x86/vdso/vdso2c.h
index f01ed4b..f42e2dd 100644
--- a/arch/x86/vdso/vdso2c.h
+++ b/arch/x86/vdso/vdso2c.h
@@ -92,7 +92,9 @@ static void BITSFUNC(copy_section)(struct BITSFUNC(fake_sections) *out,
 {
 	uint64_t flags = GET_LE(&in->sh_flags);
 
-	bool copy = flags & SHF_ALLOC;
+	bool copy = flags & SHF_ALLOC &&
+		strcmp(name, ".altinstructions") &&
+		strcmp(name, ".altinstr_replacement");
 
 	if (!copy)
 		return;
-- 
cgit v1.1


From dda1e95cee38b416b23f751cac65421d781e3c10 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Fri, 20 Jun 2014 12:20:44 -0700
Subject: x86/vdso: Create .build-id links for unstripped vdso files

With this change, doing 'make vdso_install' and telling gdb:

set debug-file-directory /lib/modules/KVER/vdso

will enable vdso debugging with symbols.  This is useful for
testing, but kernel RPM builds will probably want to manually delete
these symlinks or otherwise do something sensible when they strip
the vdso/*.so files.

If ld does not support --build-id, then the symlinks will not be
created.

Note that kernel packagers that use vdso_install may need to adjust
their packaging scripts to accomdate this change.  For example,
Fedora's scripts create build-id symlinks themselves in a different
location, so the spec should probably be updated to remove the
symlinks created by make vdso_install.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/a424b189ce3ced85fe1e82d032a20e765e0fe0d3.1403291930.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/vdso/Makefile | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index 2c1ca98..68a15c4 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -169,14 +169,24 @@ quiet_cmd_vdso = VDSO    $@
 		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'
 
 VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) \
-	-Wl,-Bsymbolic $(LTO_CFLAGS)
+	$(call cc-ldoption, -Wl$(comma)--build-id) -Wl,-Bsymbolic $(LTO_CFLAGS)
 GCOV_PROFILE := n
 
 #
-# Install the unstripped copies of vdso*.so.
+# Install the unstripped copies of vdso*.so.  If our toolchain supports
+# build-id, install .build-id links as well.
 #
 quiet_cmd_vdso_install = INSTALL $(@:install_%=%)
-      cmd_vdso_install = cp $< $(MODLIB)/vdso/$(@:install_%=%)
+define cmd_vdso_install
+	cp $< "$(MODLIB)/vdso/$(@:install_%=%)"; \
+	if readelf -n $< |grep -q 'Build ID'; then \
+	  buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \
+	  first=`echo $$buildid | cut -b-2`; \
+	  last=`echo $$buildid | cut -b3-`; \
+	  mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \
+	  ln -sf "../../$(@:install_%=%)" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \
+	fi
+endef
 
 vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%)
 
-- 
cgit v1.1


From 554086d85e71f30abe46fc014fea31929a7c6a8a Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Mon, 23 Jun 2014 14:22:15 -0700
Subject: x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The bad syscall nr paths are their own incomprehensible route
through the entry control flow.  Rearrange them to work just like
syscalls that return -ENOSYS.

This fixes an OOPS in the audit code when fast-path auditing is
enabled and sysenter gets a bad syscall nr (CVE-2014-4508).

This has probably been broken since Linux 2.6.27:
af0575bba0 i386 syscall audit fast-path

Cc: stable@vger.kernel.org
Cc: Roland McGrath <roland@redhat.com>
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/e09c499eade6fc321266dd6b54da7beb28d6991c.1403558229.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/entry_32.S | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index f0da82b..dbaa23e 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -423,9 +423,10 @@ sysenter_past_esp:
 	jnz sysenter_audit
 sysenter_do_call:
 	cmpl $(NR_syscalls), %eax
-	jae syscall_badsys
+	jae sysenter_badsys
 	call *sys_call_table(,%eax,4)
 	movl %eax,PT_EAX(%esp)
+sysenter_after_call:
 	LOCKDEP_SYS_EXIT
 	DISABLE_INTERRUPTS(CLBR_ANY)
 	TRACE_IRQS_OFF
@@ -675,7 +676,12 @@ END(syscall_fault)
 
 syscall_badsys:
 	movl $-ENOSYS,PT_EAX(%esp)
-	jmp resume_userspace
+	jmp syscall_exit
+END(syscall_badsys)
+
+sysenter_badsys:
+	movl $-ENOSYS,PT_EAX(%esp)
+	jmp sysenter_after_call
 END(syscall_badsys)
 	CFI_ENDPROC
 
-- 
cgit v1.1


From 6ba19a670c8b604e9802d30b511e6a4778118592 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Sat, 21 Jun 2014 07:31:55 -0700
Subject: x86_32, signal: Fix vdso rt_sigreturn

This commit:

    commit 6f121e548f83674ab4920a4e60afb58d4f61b829
    Author: Andy Lutomirski <luto@amacapital.net>
    Date:   Mon May 5 12:19:34 2014 -0700

        x86, vdso: Reimplement vdso.so preparation in build-time C

Contained this obvious typo:

-               restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
+               restorer = current->mm->context.vdso +
+                       selected_vdso32->sym___kernel_sigreturn;

Note the missing 'rt_' in the new code.  Fix it.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/1eb40ad923acde2e18357ef2832867432e70ac42.1403361010.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/kernel/signal.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index a0da58d..2851d63 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -363,7 +363,7 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig,
 
 		/* Set up to return from userspace.  */
 		restorer = current->mm->context.vdso +
-			selected_vdso32->sym___kernel_sigreturn;
+			selected_vdso32->sym___kernel_rt_sigreturn;
 		if (ksig->ka.sa.sa_flags & SA_RESTORER)
 			restorer = ksig->ka.sa.sa_restorer;
 		put_user_ex(restorer, &frame->pretcode);
-- 
cgit v1.1


From 46b57a76930f01ebf31230ed35af5beeccb5ad95 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Tue, 24 Jun 2014 13:46:52 -0700
Subject: x86/vdso: Move DISABLE_BRANCH_PROFILING into the vdso makefile

DISABLE_BRANCH_PROFILING turns off branch profiling (i.e. a
redefinition of 'if').  Branch profiling depends on a bunch of
kernel-internal symbols and generates extra output sections, none of
which are useful or functional in the vDSO.

It's currently turned off for vclock_gettime.c, but vgetcpu.c also
triggers branch profiling, so just turn it off in the makefile.

This fixes the build on some configurations: the vdso could contain
undefined symbols, and the fake section table overflowed due to
ftrace's added sections.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/bf1ec29e03b2bbc081f6dcaefa64db1c3a83fb21.1403642755.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/vdso/Makefile         | 4 +++-
 arch/x86/vdso/vclock_gettime.c | 3 ---
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index 68a15c4..61b04fe 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -66,7 +66,8 @@ $(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso2c FORCE
 #
 CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
        $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \
-       -fno-omit-frame-pointer -foptimize-sibling-calls
+       -fno-omit-frame-pointer -foptimize-sibling-calls \
+       -DDISABLE_BRANCH_PROFILING
 
 $(vobjs): KBUILD_CFLAGS += $(CFL)
 
@@ -149,6 +150,7 @@ KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
 KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
 KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
 KBUILD_CFLAGS_32 += -fno-omit-frame-pointer
+KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING
 $(vdso32-images:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
 
 $(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \
diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
index b2e4f49..9793322 100644
--- a/arch/x86/vdso/vclock_gettime.c
+++ b/arch/x86/vdso/vclock_gettime.c
@@ -11,9 +11,6 @@
  * Check with readelf after changing.
  */
 
-/* Disable profiling for userspace code: */
-#define DISABLE_BRANCH_PROFILING
-
 #include <uapi/linux/time.h>
 #include <asm/vgtod.h>
 #include <asm/hpet.h>
-- 
cgit v1.1


From 6a89d71078dad9b1c49ccdf1ffa656fbe36ccd1e Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@amacapital.net>
Date: Tue, 24 Jun 2014 13:46:53 -0700
Subject: x86/vdso: Error out in vdso2c if DT_RELA is present

vdso2c was checking for various types of relocations to detect when
the vdso had undefined symbols or was otherwise dependent on
relocation at load time.  Undefined symbols in the vdso would fail if
accessed at runtime, and certain implementation errors (e.g. branch
profiling or incorrect symbol visibilities) could result in data
access through the GOT that requires relocations.  This could be
as simple as:

    extern char foo;
    return foo;

Without some kind of visibility control, the compiler would assume
that foo could be interposed at load time and would generate a
relocation.

x86-64 and x32 (as opposed to i386) use explicit-addent (RELA) instead
of implicit-addent (REL) relocations for data access, and vdso2c
forgot to detect those.

Whether these bad relocations would actually fail at runtime depends
on what the linker sticks in the unrelocated references.  Nonetheless,
these relocations have no business existing in the vDSO and should be
fixed rather than silently ignored.

This error could trigger on some configurations due to branch
profiling.  The previous patch fixed that.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/74ef0c00b4d2a3b573e00a4113874e62f772e348.1403642755.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/vdso/vdso2c.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/vdso/vdso2c.h b/arch/x86/vdso/vdso2c.h
index f42e2dd..df95a2f 100644
--- a/arch/x86/vdso/vdso2c.h
+++ b/arch/x86/vdso/vdso2c.h
@@ -164,7 +164,7 @@ static void BITSFUNC(go)(void *addr, size_t len,
 	for (i = 0; dyn + i < dyn_end &&
 		     GET_LE(&dyn[i].d_tag) != DT_NULL; i++) {
 		typeof(dyn[i].d_tag) tag = GET_LE(&dyn[i].d_tag);
-		if (tag == DT_REL || tag == DT_RELSZ ||
+		if (tag == DT_REL || tag == DT_RELSZ || tag == DT_RELA ||
 		    tag == DT_RELENT || tag == DT_TEXTREL)
 			fail("vdso image contains dynamic relocations\n");
 	}
-- 
cgit v1.1


From 783ee43118dc773bc8b0342c5b230e017d5a04d0 Mon Sep 17 00:00:00 2001
From: Andrzej Zaborowski <andrew.zaborowski@intel.com>
Date: Mon, 9 Jun 2014 16:50:40 +0200
Subject: efi-pstore: Fix an overflow on 32-bit builds

In generic_id the long int timestamp is multiplied by 100000 and needs
an explicit cast to u64.

Without that the id in the resulting pstore filename is wrong and
userspace may have problems parsing it, but more importantly files in
pstore can never be deleted and may fill the EFI flash (brick device?).
This happens because when generic pstore code wants to delete a file,
it passes the id to the EFI backend which reinterpretes it and a wrong
variable name is attempted to be deleted.  There's no error message but
after remounting pstore, deleted files would reappear.

Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
---
 drivers/firmware/efi/efi-pstore.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/efi-pstore.c b/drivers/firmware/efi/efi-pstore.c
index 4b9dc83..e992abc 100644
--- a/drivers/firmware/efi/efi-pstore.c
+++ b/drivers/firmware/efi/efi-pstore.c
@@ -40,7 +40,7 @@ struct pstore_read_data {
 static inline u64 generic_id(unsigned long timestamp,
 			     unsigned int part, int count)
 {
-	return (timestamp * 100 + part) * 1000 + count;
+	return ((u64) timestamp * 100 + part) * 1000 + count;
 }
 
 static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
-- 
cgit v1.1