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authorLinus Torvalds <torvalds@linux-foundation.org>2021-10-18 06:41:39 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-10-18 06:41:39 +0300
commit6890acacdee09d7cb7c988175c895ccb4f1bb340 (patch)
tree4fd51cf892d8b44d712112ccd100d84a135b50d0
parentf644750ccc02f5d513abf314a16bec5f70d13c40 (diff)
parent86e1e054e0d2105cf32b0266cf1a64e6c26424f7 (diff)
downloadlinux-6890acacdee09d7cb7c988175c895ccb4f1bb340.tar.xz
Merge tag 'objtool_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fixes from Borislav Petkov: - Update section headers before the respective relocations to not trigger a safety check in elftoolchain's implementation of libelf - Do not add garbage data to the .rela.orc_unwind_ip section * tag 'objtool_urgent_for_v5.15_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Update section header before relocations objtool: Check for gelf_update_rel[a] failures
-rw-r--r--tools/objtool/elf.c56
1 files changed, 25 insertions, 31 deletions
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index b18f0055b50b..fee03b744a6e 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -508,6 +508,7 @@ int elf_add_reloc(struct elf *elf, struct section *sec, unsigned long offset,
list_add_tail(&reloc->list, &sec->reloc->reloc_list);
elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));
+ sec->reloc->sh.sh_size += sec->reloc->sh.sh_entsize;
sec->reloc->changed = true;
return 0;
@@ -977,63 +978,63 @@ static struct section *elf_create_reloc_section(struct elf *elf,
}
}
-static int elf_rebuild_rel_reloc_section(struct section *sec, int nr)
+static int elf_rebuild_rel_reloc_section(struct section *sec)
{
struct reloc *reloc;
- int idx = 0, size;
+ int idx = 0;
void *buf;
/* Allocate a buffer for relocations */
- size = nr * sizeof(GElf_Rel);
- buf = malloc(size);
+ buf = malloc(sec->sh.sh_size);
if (!buf) {
perror("malloc");
return -1;
}
sec->data->d_buf = buf;
- sec->data->d_size = size;
+ sec->data->d_size = sec->sh.sh_size;
sec->data->d_type = ELF_T_REL;
- sec->sh.sh_size = size;
-
idx = 0;
list_for_each_entry(reloc, &sec->reloc_list, list) {
reloc->rel.r_offset = reloc->offset;
reloc->rel.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
- gelf_update_rel(sec->data, idx, &reloc->rel);
+ if (!gelf_update_rel(sec->data, idx, &reloc->rel)) {
+ WARN_ELF("gelf_update_rel");
+ return -1;
+ }
idx++;
}
return 0;
}
-static int elf_rebuild_rela_reloc_section(struct section *sec, int nr)
+static int elf_rebuild_rela_reloc_section(struct section *sec)
{
struct reloc *reloc;
- int idx = 0, size;
+ int idx = 0;
void *buf;
/* Allocate a buffer for relocations with addends */
- size = nr * sizeof(GElf_Rela);
- buf = malloc(size);
+ buf = malloc(sec->sh.sh_size);
if (!buf) {
perror("malloc");
return -1;
}
sec->data->d_buf = buf;
- sec->data->d_size = size;
+ sec->data->d_size = sec->sh.sh_size;
sec->data->d_type = ELF_T_RELA;
- sec->sh.sh_size = size;
-
idx = 0;
list_for_each_entry(reloc, &sec->reloc_list, list) {
reloc->rela.r_offset = reloc->offset;
reloc->rela.r_addend = reloc->addend;
reloc->rela.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type);
- gelf_update_rela(sec->data, idx, &reloc->rela);
+ if (!gelf_update_rela(sec->data, idx, &reloc->rela)) {
+ WARN_ELF("gelf_update_rela");
+ return -1;
+ }
idx++;
}
@@ -1042,16 +1043,9 @@ static int elf_rebuild_rela_reloc_section(struct section *sec, int nr)
static int elf_rebuild_reloc_section(struct elf *elf, struct section *sec)
{
- struct reloc *reloc;
- int nr;
-
- nr = 0;
- list_for_each_entry(reloc, &sec->reloc_list, list)
- nr++;
-
switch (sec->sh.sh_type) {
- case SHT_REL: return elf_rebuild_rel_reloc_section(sec, nr);
- case SHT_RELA: return elf_rebuild_rela_reloc_section(sec, nr);
+ case SHT_REL: return elf_rebuild_rel_reloc_section(sec);
+ case SHT_RELA: return elf_rebuild_rela_reloc_section(sec);
default: return -1;
}
}
@@ -1111,12 +1105,6 @@ int elf_write(struct elf *elf)
/* Update changed relocation sections and section headers: */
list_for_each_entry(sec, &elf->sections, list) {
if (sec->changed) {
- if (sec->base &&
- elf_rebuild_reloc_section(elf, sec)) {
- WARN("elf_rebuild_reloc_section");
- return -1;
- }
-
s = elf_getscn(elf->elf, sec->idx);
if (!s) {
WARN_ELF("elf_getscn");
@@ -1127,6 +1115,12 @@ int elf_write(struct elf *elf)
return -1;
}
+ if (sec->base &&
+ elf_rebuild_reloc_section(elf, sec)) {
+ WARN("elf_rebuild_reloc_section");
+ return -1;
+ }
+
sec->changed = false;
elf->changed = true;
}