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authorFangrui Song <maskray@google.com>2022-04-20 13:52:45 -0700
committerFangrui Song <maskray@google.com>2022-04-20 13:52:45 -0700
commit84e02af1ebc9988126eebe60bf19226cea835623 (patch)
treeb836e59714fbb7e863699069b500e1a8a30f7210 /elf/do-rel.h
parenta8e9b5b8079d18116ca69c9797e77804ecf2ee7e (diff)
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elf: Move elf_dynamic_do_Rel RTLD_BOOTSTRAP branches outside
elf_dynamic_do_Rel checks RTLD_BOOTSTRAP in several #ifdef branches. Create an outside RTLD_BOOTSTRAP branch to simplify reasoning about the function at the cost of a few duplicate lines. Since dl_naudit is zero in RTLD_BOOTSTRAP code, the RTLD_BOOTSTRAP branch can avoid _dl_audit_symbind calls to decrease code size. Reviewed-by: Adheemrval Zanella <adhemerval.zanella@linaro.org>
Diffstat (limited to 'elf/do-rel.h')
-rw-r--r--elf/do-rel.h49
1 files changed, 28 insertions, 21 deletions
diff --git a/elf/do-rel.h b/elf/do-rel.h
index d3e0222..27b9b9f 100644
--- a/elf/do-rel.h
+++ b/elf/do-rel.h
@@ -45,15 +45,35 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
__typeof (((ElfW(Dyn) *) 0)->d_un.d_val) nrelative,
int lazy, int skip_ifunc)
{
- const ElfW(Rel) *r = (const void *) reladdr;
+ const ElfW(Rel) *relative = (const void *) reladdr;
+ const ElfW(Rel) *r = relative + nrelative;
const ElfW(Rel) *end = (const void *) (reladdr + relsize);
ElfW(Addr) l_addr = map->l_addr;
-# if defined ELF_MACHINE_IRELATIVE && !defined RTLD_BOOTSTRAP
+ const ElfW(Sym) *const symtab
+ = (const void *) D_PTR (map, l_info[DT_SYMTAB]);
+
+#ifdef RTLD_BOOTSTRAP
+ for (; relative < r; ++relative)
+ DO_ELF_MACHINE_REL_RELATIVE (map, l_addr, relative);
+
+ const ElfW (Half) *const version
+ = (const void *) D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
+ for (; r < end; ++r)
+ {
+ ElfW (Half) ndx = version[ELFW (R_SYM) (r->r_info)] & 0x7fff;
+ const ElfW (Sym) *sym = &symtab[ELFW (R_SYM) (r->r_info)];
+ void *const r_addr_arg = (void *) (l_addr + r->r_offset);
+ const struct r_found_version *rversion = &map->l_versions[ndx];
+
+ elf_machine_rel (map, scope, r, sym, rversion, r_addr_arg, skip_ifunc);
+ }
+#else /* !RTLD_BOOTSTRAP */
+# if defined ELF_MACHINE_IRELATIVE
const ElfW(Rel) *r2 = NULL;
const ElfW(Rel) *end2 = NULL;
# endif
-#if (!defined DO_RELA || !defined ELF_MACHINE_PLT_REL) && !defined RTLD_BOOTSTRAP
+#if !defined DO_RELA || !defined ELF_MACHINE_PLT_REL
/* We never bind lazily during ld.so bootstrap. Unfortunately gcc is
not clever enough to see through all the function calls to realize
that. */
@@ -82,12 +102,6 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
else
#endif
{
- const ElfW(Sym) *const symtab =
- (const void *) D_PTR (map, l_info[DT_SYMTAB]);
- const ElfW(Rel) *relative = r;
- r += nrelative;
-
-#ifndef RTLD_BOOTSTRAP
/* This is defined in rtld.c, but nowhere in the static libc.a; make
the reference weak so static programs can still link. This
declaration cannot be done when compiling rtld.c (i.e. #ifdef
@@ -106,16 +120,10 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
memory_loc += l_addr... */
if (l_addr != 0)
# endif
-#endif
for (; relative < r; ++relative)
DO_ELF_MACHINE_REL_RELATIVE (map, l_addr, relative);
-#ifdef RTLD_BOOTSTRAP
- /* The dynamic linker always uses versioning. */
- assert (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL);
-#else
if (map->l_info[VERSYMIDX (DT_VERSYM)])
-#endif
{
const ElfW(Half) *const version =
(const void *) D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
@@ -126,7 +134,7 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
const ElfW(Sym) *sym = &symtab[ELFW(R_SYM) (r->r_info)];
void *const r_addr_arg = (void *) (l_addr + r->r_offset);
const struct r_found_version *rversion = &map->l_versions[ndx];
-#if defined ELF_MACHINE_IRELATIVE && !defined RTLD_BOOTSTRAP
+#if defined ELF_MACHINE_IRELATIVE
if (ELFW(R_TYPE) (r->r_info) == ELF_MACHINE_IRELATIVE)
{
if (r2 == NULL)
@@ -138,7 +146,7 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
elf_machine_rel (map, scope, r, sym, rversion, r_addr_arg,
skip_ifunc);
-#if defined SHARED && !defined RTLD_BOOTSTRAP
+#if defined SHARED
if (ELFW(R_TYPE) (r->r_info) == ELF_MACHINE_JMP_SLOT
&& GLRO(dl_naudit) > 0)
{
@@ -151,7 +159,7 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
#endif
}
-#if defined ELF_MACHINE_IRELATIVE && !defined RTLD_BOOTSTRAP
+#if defined ELF_MACHINE_IRELATIVE
if (r2 != NULL)
for (; r2 <= end2; ++r2)
if (ELFW(R_TYPE) (r2->r_info) == ELF_MACHINE_IRELATIVE)
@@ -166,7 +174,6 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
}
#endif
}
-#ifndef RTLD_BOOTSTRAP
else
{
for (; r < end; ++r)
@@ -184,7 +191,7 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
# endif
elf_machine_rel (map, scope, r, sym, NULL, r_addr_arg,
skip_ifunc);
-# if defined SHARED && !defined RTLD_BOOTSTRAP
+# if defined SHARED
if (ELFW(R_TYPE) (r->r_info) == ELF_MACHINE_JMP_SLOT
&& GLRO(dl_naudit) > 0)
{
@@ -207,8 +214,8 @@ elf_dynamic_do_Rel (struct link_map *map, struct r_scope_elem *scope[],
skip_ifunc);
# endif
}
-#endif
}
+#endif /* !RTLD_BOOTSTRAP */
}
#undef elf_dynamic_do_Rel