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Diffstat (limited to 'elf/dl-runtime.c')
-rw-r--r--elf/dl-runtime.c174
1 files changed, 85 insertions, 89 deletions
diff --git a/elf/dl-runtime.c b/elf/dl-runtime.c
index e7132ed832..3f09d72c32 100644
--- a/elf/dl-runtime.c
+++ b/elf/dl-runtime.c
@@ -70,37 +70,16 @@ _dl_object_relocation_scope (struct link_map *l)
#include "dynamic-link.h"
-/* Figure out the right type, Rel or Rela. */
-#define elf_machine_rel 1
-#define elf_machine_rela 2
-#if elf_machine_relplt == elf_machine_rel
-# define PLTREL ElfW(Rel)
-#elif elf_machine_relplt == elf_machine_rela
-# define PLTREL ElfW(Rela)
+#if !defined ELF_MACHINE_NO_RELA || ELF_MACHINE_NO_REL
+# define PLTREL ElfW(Rela)
#else
-# error "dl-machine.h bug: elf_machine_relplt not rel or rela"
+# define PLTREL ElfW(Rel)
#endif
-#undef elf_machine_rel
-#undef elf_machine_rela
#ifndef VERSYMIDX
# define VERSYMIDX(sym) (DT_NUM + DT_PROCNUM + DT_VERSIONTAGIDX (sym))
#endif
-#ifndef ELF_FIXUP_RETURN_VALUE
-#define ELF_FIXUP_RETURN_VALUE(map, result) (result)
-#endif
-
-/* We need to define the function as a local symbol so that the reference
- in the trampoline code will be a local PC-relative call. Tell the
- compiler not to worry that the function appears not to be called. */
-
-static ElfW(Addr) fixup (
-#ifdef ELF_MACHINE_RUNTIME_FIXUP_ARGS
- ELF_MACHINE_RUNTIME_FIXUP_ARGS,
-#endif
- struct link_map *l, ElfW(Word) reloc_offset)
- __attribute__ ((unused));
/* This function is called through a special trampoline from the PLT the
first time each PLT entry is called. We must perform the relocation
@@ -109,7 +88,7 @@ static ElfW(Addr) fixup (
to that address. Future calls will bounce directly from the PLT to the
function. */
-static ElfW(Addr)
+static ElfW(Addr) __attribute__ ((unused))
fixup (
#ifdef ELF_MACHINE_RUNTIME_FIXUP_ARGS
ELF_MACHINE_RUNTIME_FIXUP_ARGS,
@@ -124,57 +103,63 @@ fixup (
const PLTREL *const reloc
= (const void *) (l->l_addr + l->l_info[DT_JMPREL]->d_un.d_ptr +
reloc_offset);
- ElfW(Addr) *const rel_addr = (ElfW(Addr) *)(l->l_addr + reloc->r_offset);
+ const ElfW(Sym) *sym = &symtab[ELFW(R_SYM) (reloc->r_info)];
+ void *const rel_addr = (void *)(l->l_addr + reloc->r_offset);
+ ElfW(Addr) value;
/* Set up the scope to find symbols referenced by this object. */
struct link_map **scope = _dl_object_relocation_scope (l);
- {
- const struct r_found_version *here_version;
-
- /* This macro is used as a callback from the elf_machine_relplt code. */
-#define RESOLVE(ref, version, flags) \
- ((version) != NULL && (version)->hash != 0 \
- ? _dl_lookup_versioned_symbol (strtab + (*ref)->st_name, (ref), scope, \
- l->l_name, (version), (flags)) \
- : _dl_lookup_symbol (strtab + (*ref)->st_name, (ref), scope, \
- l->l_name, (flags)))
-#include "dynamic-link.h"
+ /* Sanity check that we're really looking at a PLT relocation. */
+ assert (ELFW(R_TYPE)(reloc->r_info) == ELF_MACHINE_JMP_SLOT);
- /* Perform the specified relocation. */
- if (l->l_info[VERSYMIDX (DT_VERSYM)])
+ /* Look up the target symbol. */
+ switch (l->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
+ {
+ default:
{
- const ElfW(Half) *version =
- (const ElfW(Half) *) (l->l_addr +
- l->l_info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr);
- ElfW(Half) ndx = version[ELFW(R_SYM) (reloc->r_info)];
-
- here_version = &l->l_versions[ndx];
+ const ElfW(Half) *vernum = (const ElfW(Half) *)
+ (l->l_addr + l->l_info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr);
+ ElfW(Half) ndx = vernum[ELFW(R_SYM) (reloc->r_info)];
+ const struct r_found_version *version = &l->l_versions[ndx];
+
+ if (version->hash != 0)
+ {
+ value = _dl_lookup_versioned_symbol(strtab + sym->st_name,
+ &sym, scope, l->l_name,
+ version, ELF_MACHINE_JMP_SLOT);
+ break;
+ }
}
- else
- here_version = NULL;
+ case 0:
+ value = _dl_lookup_symbol (strtab + sym->st_name, &sym, scope,
+ l->l_name, ELF_MACHINE_JMP_SLOT);
+ }
+
+ /* Currently value contains the base load address of the object
+ that defines sym. Now add in the symbol offset. */
+ value = (sym ? value + sym->st_value : 0);
+
+ /* And now the relocation addend. */
+#ifndef ELF_MACHINE_NO_RELA
+ if (l->l_info[DT_PLTRELSZ]->d_un.d_val == sizeof (ElfW(Rela)))
+ value += reloc->r_addend;
+#elif ELF_MACHINE_NO_REL
+ value += reloc->r_addend;
+#endif
- elf_machine_relplt (l, reloc, &symtab[ELFW(R_SYM) (reloc->r_info)],
- here_version, (void *) rel_addr);
- }
+ /* Finally, fix up the plt itself. */
+ elf_machine_fixup_plt (l, reloc, rel_addr, value);
*_dl_global_scope_end = NULL;
- /* Return the address that was written by the relocation. */
- return ELF_FIXUP_RETURN_VALUE(l, *rel_addr);
+ return value;
}
#ifndef PROF
-static ElfW(Addr)
-profile_fixup (
-#ifdef ELF_MACHINE_RUNTIME_FIXUP_ARGS
- ELF_MACHINE_RUNTIME_FIXUP_ARGS,
-#endif
- struct link_map *l, ElfW(Word) reloc_offset, ElfW(Addr) retaddr)
- __attribute__ ((unused));
-static ElfW(Addr)
+static ElfW(Addr) __attribute__ ((unused))
profile_fixup (
#ifdef ELF_MACHINE_RUNTIME_FIXUP_ARGS
ELF_MACHINE_RUNTIME_FIXUP_ARGS,
@@ -182,6 +167,7 @@ profile_fixup (
struct link_map *l, ElfW(Word) reloc_offset, ElfW(Addr) retaddr)
{
void (*mcount_fct) (ElfW(Addr), ElfW(Addr)) = _dl_mcount;
+
const ElfW(Sym) *const symtab
= (const ElfW(Sym) *) (l->l_addr + l->l_info[DT_SYMTAB]->d_un.d_ptr);
const char *strtab =
@@ -190,47 +176,57 @@ profile_fixup (
const PLTREL *const reloc
= (const void *) (l->l_addr + l->l_info[DT_JMPREL]->d_un.d_ptr +
reloc_offset);
- ElfW(Addr) result;
+ const ElfW(Sym) *sym = &symtab[ELFW(R_SYM) (reloc->r_info)];
+ ElfW(Addr) value;
/* Set up the scope to find symbols referenced by this object. */
struct link_map **scope = _dl_object_relocation_scope (l);
- {
- const struct r_found_version *here_version;
+ /* Sanity check that we're really looking at a PLT relocation. */
+ assert (ELFW(R_TYPE)(reloc->r_info) == ELF_MACHINE_JMP_SLOT);
- /* This macro is used as a callback from the elf_machine_relplt code. */
-#define RESOLVE(ref, version, flags) \
- ((version) != NULL && (version)->hash != 0 \
- ? _dl_lookup_versioned_symbol (strtab + (*ref)->st_name, (ref), scope, \
- l->l_name, (version), (flags)) \
- : _dl_lookup_symbol (strtab + (*ref)->st_name, (ref), scope, \
- l->l_name, (flags)))
-#include "dynamic-link.h"
-
- /* Perform the specified relocation. */
- if (l->l_info[VERSYMIDX (DT_VERSYM)])
+ /* Look up the target symbol. */
+ switch (l->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
+ {
+ default:
{
- const ElfW(Half) *version =
- (const ElfW(Half) *) (l->l_addr +
- l->l_info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr);
- ElfW(Half) ndx = version[ELFW(R_SYM) (reloc->r_info)];
-
- here_version = &l->l_versions[ndx];
+ const ElfW(Half) *vernum = (const ElfW(Half) *)
+ (l->l_addr + l->l_info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr);
+ ElfW(Half) ndx = vernum[ELFW(R_SYM) (reloc->r_info)];
+ const struct r_found_version *version = &l->l_versions[ndx];
+
+ if (version->hash != 0)
+ {
+ value = _dl_lookup_versioned_symbol(strtab + sym->st_name,
+ &sym, scope, l->l_name,
+ version, ELF_MACHINE_JMP_SLOT);
+ break;
+ }
}
- else
- here_version = NULL;
+ case 0:
+ value = _dl_lookup_symbol (strtab + sym->st_name, &sym, scope,
+ l->l_name, ELF_MACHINE_JMP_SLOT);
+ }
+
+ /* Currently value contains the base load address of the object
+ that defines sym. Now add in the symbol offset. */
+ value = (sym ? value + sym->st_value : 0);
- elf_machine_relplt (l, reloc, &symtab[ELFW(R_SYM) (reloc->r_info)],
- here_version, (void *) &result);
- }
+ /* And now the relocation addend. */
+#ifndef ELF_MACHINE_NO_RELA
+ if (l->l_info[DT_PLTRELSZ]->d_un.d_val == sizeof (ElfW(Rela)))
+ value += reloc->r_addend;
+#elif ELF_MACHINE_NO_REL
+ value += reloc->r_addend;
+#endif
*_dl_global_scope_end = NULL;
- (*mcount_fct) (retaddr, ELF_FIXUP_RETURN_VALUE (l, result));
+ (*mcount_fct) (retaddr, value);
- /* Return the address that was written by the relocation. */
- return ELF_FIXUP_RETURN_VALUE (l, result);
+ return value;
}
-#endif
+
+#endif /* PROF */
/* This macro is defined in dl-machine.h to define the entry point called
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-27 19:37:11 +0000