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-rw-r--r--arch/x86/vdso/Makefile58
-rw-r--r--arch/x86/vdso/vclock_gettime.c3
-rw-r--r--arch/x86/vdso/vdso-fakesections.c21
-rw-r--r--arch/x86/vdso/vdso-layout.lds.S64
-rw-r--r--arch/x86/vdso/vdso.lds.S2
-rw-r--r--arch/x86/vdso/vdso2c.c92
-rw-r--r--arch/x86/vdso/vdso2c.h197
-rw-r--r--arch/x86/vdso/vdso32/vdso-fakesections.c1
-rw-r--r--arch/x86/vdso/vdsox32.lds.S2
-rw-r--r--arch/x86/vdso/vma.c4
10 files changed, 339 insertions, 105 deletions
diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index 9769df09403..61b04fe36e6 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -9,18 +9,8 @@ VDSOX32-$(CONFIG_X86_X32_ABI) := y
VDSO32-$(CONFIG_X86_32) := y
VDSO32-$(CONFIG_COMPAT) := y
-vdso-install-$(VDSO64-y) += vdso.so
-vdso-install-$(VDSOX32-y) += vdsox32.so
-vdso-install-$(VDSO32-y) += $(vdso32-images)
-
-
# files to link into the vdso
-vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o
-
-vobjs-$(VDSOX32-y) += $(vobjx32s-compat)
-
-# Filter out x32 objects.
-vobj64s := $(filter-out $(vobjx32s-compat),$(vobjs-y))
+vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o vdso-fakesections.o
# files to link into kernel
obj-y += vma.o
@@ -34,7 +24,7 @@ vdso_img-$(VDSO32-y) += 32-sysenter
obj-$(VDSO32-y) += vdso32-setup.o
-vobjs := $(foreach F,$(vobj64s),$(obj)/$F)
+vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
$(obj)/vdso.o: $(obj)/vdso.so
@@ -76,7 +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)
@@ -104,7 +95,13 @@ VDSO_LDFLAGS_vdsox32.lds = -Wl,-m,elf32_x86_64 \
-Wl,-z,max-page-size=4096 \
-Wl,-z,common-page-size=4096
-vobjx32s-y := $(vobj64s:.o=-x32.o)
+# 64-bit objects to re-brand as x32
+vobjs64-for-x32 := $(filter-out $(vobjs-nox32),$(vobjs-y))
+
+# x32-rebranded versions
+vobjx32s-y := $(vobjs64-for-x32:.o=-x32.o)
+
+# same thing, but in the output directory
vobjx32s := $(foreach F,$(vobjx32s-y),$(obj)/$F)
# Convert 64bit object file to x32 for x32 vDSO.
@@ -137,7 +134,7 @@ 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)/%)
@@ -153,11 +150,13 @@ 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 \
$(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)
@@ -172,19 +171,34 @@ 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 copy of vdso*.so listed in $(vdso-install-y).
+# Install the unstripped copies of vdso*.so. If our toolchain supports
+# build-id, install .build-id links as well.
#
-quiet_cmd_vdso_install = INSTALL $@
- cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
-$(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE
+quiet_cmd_vdso_install = INSTALL $(@: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 := $(vdso_img_sodbg:%.dbg=install_%)
+
+$(MODLIB)/vdso: FORCE
@mkdir -p $(MODLIB)/vdso
+
+$(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso FORCE
$(call cmd,vdso_install)
-PHONY += vdso_install $(vdso-install-y)
-vdso_install: $(vdso-install-y)
+PHONY += vdso_install $(vdso_img_insttargets)
+vdso_install: $(vdso_img_insttargets) FORCE
clean-files := vdso32-syscall* vdso32-sysenter* vdso32-int80*
diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
index b2e4f493e5b..9793322751e 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>
diff --git a/arch/x86/vdso/vdso-fakesections.c b/arch/x86/vdso/vdso-fakesections.c
new file mode 100644
index 00000000000..aa5fbfab20a
--- /dev/null
+++ b/arch/x86/vdso/vdso-fakesections.c
@@ -0,0 +1,21 @@
+/*
+ * Copyright 2014 Andy Lutomirski
+ * Subject to the GNU Public License, v.2
+ *
+ * String table for loadable section headers. See vdso2c.h for why
+ * this exists.
+ */
+
+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"
+ ".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 2ec72f651eb..9197544eea9 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 13
+
SECTIONS
{
. = SIZEOF_HEADERS;
@@ -18,36 +28,53 @@ SECTIONS
.gnu.version_d : { *(.gnu.version_d) }
.gnu.version_r : { *(.gnu.version_r) }
+ .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
+ * 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
+
+
.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*) } :text
- .data : {
- *(.data*)
- *(.sdata*)
- *(.got.plt) *(.got)
- *(.gnu.linkonce.d.*)
- *(.bss*)
- *(.dynbss*)
- *(.gnu.linkonce.b.*)
- }
-
- .altinstructions : { *(.altinstructions) }
- .altinstr_replacement : { *(.altinstr_replacement) }
/*
- * 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
@@ -75,6 +102,7 @@ SECTIONS
/DISCARD/ : {
*(.discard)
*(.discard.*)
+ *(__bug_table)
}
}
diff --git a/arch/x86/vdso/vdso.lds.S b/arch/x86/vdso/vdso.lds.S
index 75e3404c83b..6807932643c 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 450ac6eaf61..238dbe82776 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))
@@ -54,7 +67,7 @@ static void fail(const char *format, ...)
}
/*
- * Evil macros to do a little-endian read.
+ * Evil macros for little-endian reads and writes
*/
#define GLE(x, bits, ifnot) \
__builtin_choose_expr( \
@@ -62,45 +75,42 @@ static void fail(const char *format, ...)
(__typeof__(*(x)))get_unaligned_le##bits(x), ifnot)
extern void bad_get_le(void);
-#define LAST_LE(x) \
+#define LAST_GLE(x) \
__builtin_choose_expr(sizeof(*(x)) == 1, *(x), bad_get_le())
#define GET_LE(x) \
- GLE(x, 64, GLE(x, 32, GLE(x, 16, LAST_LE(x))))
+ GLE(x, 64, GLE(x, 32, GLE(x, 16, LAST_GLE(x))))
+
+#define PLE(x, val, bits, ifnot) \
+ __builtin_choose_expr( \
+ (sizeof(*(x)) == bits/8), \
+ put_unaligned_le##bits((val), (x)), ifnot)
+
+extern void bad_put_le(void);
+#define LAST_PLE(x, val) \
+ __builtin_choose_expr(sizeof(*(x)) == 1, *(x) = (val), bad_put_le())
+
+#define PUT_LE(x, val) \
+ PLE(x, val, 64, PLE(x, val, 32, PLE(x, val, 16, LAST_PLE(x, val))))
+
#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 8a074637a57..11b65d4f941 100644
--- a/arch/x86/vdso/vdso2c.h
+++ b/arch/x86/vdso/vdso2c.h
@@ -4,21 +4,139 @@
* are built for 32-bit userspace.
*/
-static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
+/*
+ * 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 &&
+ (GET_LE(&in->sh_size) ||
+ (GET_LE(&in->sh_type) != SHT_RELA &&
+ GET_LE(&in->sh_type) != SHT_REL)) &&
+ strcmp(name, ".altinstructions") &&
+ strcmp(name, ".altinstr_replacement");
+
+ 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)
{
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] = {};
- Elf_Phdr *pt = (Elf_Phdr *)(addr + GET_LE(&hdr->e_phoff));
+ struct BITSFUNC(fake_sections) fake_sections = {};
+
+ 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++) {
@@ -49,7 +167,7 @@ static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
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");
}
@@ -59,7 +177,7 @@ 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;
@@ -80,20 +198,62 @@ 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);
+
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, "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++) {
@@ -102,22 +262,17 @@ static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
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. */
- hdr->e_shoff = 0;
- hdr->e_shentsize = 0;
- hdr->e_shnum = 0;
- hdr->e_shstrndx = htole16(SHN_UNDEF);
-
if (!name) {
fwrite(addr, load_size, 1, outfile);
return;
@@ -155,9 +310,9 @@ static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name)
(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 00000000000..541468e2526
--- /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 46b991b578a..697c11ece90 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"
/*
diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c
index e1513c47872..5a5176de8d0 100644
--- a/arch/x86/vdso/vma.c
+++ b/arch/x86/vdso/vma.c
@@ -62,6 +62,9 @@ struct linux_binprm;
Only used for the 64-bit and x32 vdsos. */
static unsigned long vdso_addr(unsigned long start, unsigned len)
{
+#ifdef CONFIG_X86_32
+ return 0;
+#else
unsigned long addr, end;
unsigned offset;
end = (start + PMD_SIZE - 1) & PMD_MASK;
@@ -83,6 +86,7 @@ static unsigned long vdso_addr(unsigned long start, unsigned len)
addr = align_vdso_addr(addr);
return addr;
+#endif
}
static int map_vdso(const struct vdso_image *image, bool calculate_addr)
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-21 06:58:39 +0000