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-rw-r--r--libexec/rtld-elf/amd64/reloc.c351
1 files changed, 163 insertions, 188 deletions
diff --git a/libexec/rtld-elf/amd64/reloc.c b/libexec/rtld-elf/amd64/reloc.c
index 7b002b2..35f33cc 100644
--- a/libexec/rtld-elf/amd64/reloc.c
+++ b/libexec/rtld-elf/amd64/reloc.c
@@ -125,213 +125,188 @@ reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, int flags,
const Elf_Rela *relalim;
const Elf_Rela *rela;
SymCache *cache;
- int r = -1;
+ const Elf_Sym *def;
+ const Obj_Entry *defobj;
+ Elf_Addr *where, symval;
+ Elf32_Addr *where32;
+ int r;
+ r = -1;
/*
* The dynamic loader may be called from a thread, we have
* limited amounts of stack available so we cannot use alloca().
*/
if (obj != obj_rtld) {
- cache = calloc(obj->dynsymcount, sizeof(SymCache));
- /* No need to check for NULL here */
+ cache = calloc(obj->dynsymcount, sizeof(SymCache));
+ /* No need to check for NULL here */
} else
- cache = NULL;
+ cache = NULL;
- relalim = (const Elf_Rela *) ((caddr_t) obj->rela + obj->relasize);
+ relalim = (const Elf_Rela *)((caddr_t)obj->rela + obj->relasize);
for (rela = obj->rela; rela < relalim; rela++) {
- Elf_Addr *where = (Elf_Addr *) (obj->relocbase + rela->r_offset);
- Elf32_Addr *where32 = (Elf32_Addr *)where;
-
- switch (ELF_R_TYPE(rela->r_info)) {
-
- case R_X86_64_NONE:
- break;
-
- case R_X86_64_64:
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
- goto done;
-
- *where = (Elf_Addr) (defobj->relocbase + def->st_value + rela->r_addend);
- }
- break;
-
- case R_X86_64_PC32:
- /*
- * I don't think the dynamic linker should ever see this
- * type of relocation. But the binutils-2.6 tools sometimes
- * generate it.
- */
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
- goto done;
-
- *where32 = (Elf32_Addr) (unsigned long) (defobj->relocbase +
- def->st_value + rela->r_addend - (Elf_Addr) where);
- }
- break;
- /* missing: R_X86_64_GOT32 R_X86_64_PLT32 */
-
- case R_X86_64_COPY:
/*
- * These are deferred until all other relocations have
- * been done. All we do here is make sure that the COPY
- * relocation is not in a shared library. They are allowed
- * only in executable files.
+ * First, resolve symbol for relocations which
+ * reference symbols.
*/
- if (!obj->mainprog) {
- _rtld_error("%s: Unexpected R_X86_64_COPY relocation"
- " in shared library", obj->path);
- goto done;
- }
- break;
-
- case R_X86_64_GLOB_DAT:
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
- goto done;
-
- *where = (Elf_Addr) (defobj->relocbase + def->st_value);
- }
- break;
-
- case R_X86_64_TPOFF64:
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
- goto done;
-
- /*
- * We lazily allocate offsets for static TLS as we
- * see the first relocation that references the
- * TLS block. This allows us to support (small
- * amounts of) static TLS in dynamically loaded
- * modules. If we run out of space, we generate an
- * error.
- */
- if (!defobj->tls_done) {
- if (!allocate_tls_offset((Obj_Entry*) defobj)) {
- _rtld_error("%s: No space available for static "
- "Thread Local Storage", obj->path);
- goto done;
+ switch (ELF_R_TYPE(rela->r_info)) {
+ case R_X86_64_64:
+ case R_X86_64_PC32:
+ case R_X86_64_GLOB_DAT:
+ case R_X86_64_TPOFF64:
+ case R_X86_64_TPOFF32:
+ case R_X86_64_DTPMOD64:
+ case R_X86_64_DTPOFF64:
+ case R_X86_64_DTPOFF32:
+ def = find_symdef(ELF_R_SYM(rela->r_info), obj,
+ &defobj, flags, cache, lockstate);
+ if (def == NULL)
+ goto done;
+ /*
+ * If symbol is IFUNC, only perform relocation
+ * when caller allowed it by passing
+ * SYMLOOK_IFUNC flag. Skip the relocations
+ * otherwise.
+ *
+ * Also error out in case IFUNC relocations
+ * are specified for TLS, which cannot be
+ * usefully interpreted.
+ */
+ if (ELF_ST_TYPE(def->st_info) == STT_GNU_IFUNC) {
+ switch (ELF_R_TYPE(rela->r_info)) {
+ case R_X86_64_64:
+ case R_X86_64_PC32:
+ case R_X86_64_GLOB_DAT:
+ if ((flags & SYMLOOK_IFUNC) == 0) {
+ obj->non_plt_gnu_ifunc = true;
+ continue;
+ }
+ symval = (Elf_Addr)rtld_resolve_ifunc(
+ defobj, def);
+ break;
+ case R_X86_64_TPOFF64:
+ case R_X86_64_TPOFF32:
+ case R_X86_64_DTPMOD64:
+ case R_X86_64_DTPOFF64:
+ case R_X86_64_DTPOFF32:
+ _rtld_error("%s: IFUNC for TLS reloc",
+ obj->path);
+ goto done;
+ }
+ } else {
+ if ((flags & SYMLOOK_IFUNC) != 0)
+ continue;
+ symval = (Elf_Addr)defobj->relocbase +
+ def->st_value;
}
- }
-
- *where = (Elf_Addr) (def->st_value - defobj->tlsoffset +
- rela->r_addend);
+ break;
+ default:
+ if ((flags & SYMLOOK_IFUNC) != 0)
+ continue;
+ break;
}
- break;
-
- case R_X86_64_TPOFF32:
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
- goto done;
-
- /*
- * We lazily allocate offsets for static TLS as we
- * see the first relocation that references the
- * TLS block. This allows us to support (small
- * amounts of) static TLS in dynamically loaded
- * modules. If we run out of space, we generate an
- * error.
- */
- if (!defobj->tls_done) {
- if (!allocate_tls_offset((Obj_Entry*) defobj)) {
- _rtld_error("%s: No space available for static "
- "Thread Local Storage", obj->path);
- goto done;
+ where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
+ where32 = (Elf32_Addr *)where;
+
+ switch (ELF_R_TYPE(rela->r_info)) {
+ case R_X86_64_NONE:
+ break;
+ case R_X86_64_64:
+ *where = symval + rela->r_addend;
+ break;
+ case R_X86_64_PC32:
+ /*
+ * I don't think the dynamic linker should
+ * ever see this type of relocation. But the
+ * binutils-2.6 tools sometimes generate it.
+ */
+ *where32 = (Elf32_Addr)(unsigned long)(symval +
+ rela->r_addend - (Elf_Addr)where);
+ break;
+ /* missing: R_X86_64_GOT32 R_X86_64_PLT32 */
+ case R_X86_64_COPY:
+ /*
+ * These are deferred until all other relocations have
+ * been done. All we do here is make sure that the COPY
+ * relocation is not in a shared library. They are allowed
+ * only in executable files.
+ */
+ if (!obj->mainprog) {
+ _rtld_error("%s: Unexpected R_X86_64_COPY "
+ "relocation in shared library", obj->path);
+ goto done;
}
- }
-
- *where32 = (Elf32_Addr) (def->st_value -
- defobj->tlsoffset +
- rela->r_addend);
- }
- break;
-
- case R_X86_64_DTPMOD64:
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
- goto done;
-
- *where += (Elf_Addr) defobj->tlsindex;
- }
- break;
-
- case R_X86_64_DTPOFF64:
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
- goto done;
-
- *where += (Elf_Addr) (def->st_value + rela->r_addend);
- }
- break;
-
- case R_X86_64_DTPOFF32:
- {
- const Elf_Sym *def;
- const Obj_Entry *defobj;
-
- def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
- flags, cache, lockstate);
- if (def == NULL)
+ break;
+ case R_X86_64_GLOB_DAT:
+ *where = symval;
+ break;
+ case R_X86_64_TPOFF64:
+ /*
+ * We lazily allocate offsets for static TLS
+ * as we see the first relocation that
+ * references the TLS block. This allows us to
+ * support (small amounts of) static TLS in
+ * dynamically loaded modules. If we run out
+ * of space, we generate an error.
+ */
+ if (!defobj->tls_done) {
+ if (!allocate_tls_offset((Obj_Entry*) defobj)) {
+ _rtld_error("%s: No space available "
+ "for static Thread Local Storage",
+ obj->path);
+ goto done;
+ }
+ }
+ *where = (Elf_Addr)(def->st_value - defobj->tlsoffset +
+ rela->r_addend);
+ break;
+ case R_X86_64_TPOFF32:
+ /*
+ * We lazily allocate offsets for static TLS
+ * as we see the first relocation that
+ * references the TLS block. This allows us to
+ * support (small amounts of) static TLS in
+ * dynamically loaded modules. If we run out
+ * of space, we generate an error.
+ */
+ if (!defobj->tls_done) {
+ if (!allocate_tls_offset((Obj_Entry*) defobj)) {
+ _rtld_error("%s: No space available "
+ "for static Thread Local Storage",
+ obj->path);
+ goto done;
+ }
+ }
+ *where32 = (Elf32_Addr)(def->st_value -
+ defobj->tlsoffset + rela->r_addend);
+ break;
+ case R_X86_64_DTPMOD64:
+ *where += (Elf_Addr)defobj->tlsindex;
+ break;
+ case R_X86_64_DTPOFF64:
+ *where += (Elf_Addr)(def->st_value + rela->r_addend);
+ break;
+ case R_X86_64_DTPOFF32:
+ *where32 += (Elf32_Addr)(def->st_value +
+ rela->r_addend);
+ break;
+ case R_X86_64_RELATIVE:
+ *where = (Elf_Addr)(obj->relocbase + rela->r_addend);
+ break;
+ /*
+ * missing:
+ * R_X86_64_GOTPCREL, R_X86_64_32, R_X86_64_32S, R_X86_64_16,
+ * R_X86_64_PC16, R_X86_64_8, R_X86_64_PC8
+ */
+ default:
+ _rtld_error("%s: Unsupported relocation type %u"
+ " in non-PLT relocations\n", obj->path,
+ (unsigned int)ELF_R_TYPE(rela->r_info));
goto done;
-
- *where32 += (Elf32_Addr) (def->st_value + rela->r_addend);
}
- break;
-
- case R_X86_64_RELATIVE:
- *where = (Elf_Addr)(obj->relocbase + rela->r_addend);
- break;
-
- /* missing: R_X86_64_GOTPCREL, R_X86_64_32, R_X86_64_32S, R_X86_64_16, R_X86_64_PC16, R_X86_64_8, R_X86_64_PC8 */
-
- default:
- _rtld_error("%s: Unsupported relocation type %u"
- " in non-PLT relocations\n", obj->path,
- (unsigned int)ELF_R_TYPE(rela->r_info));
- goto done;
- }
}
r = 0;
done:
- if (cache != NULL)
- free(cache);
+ free(cache);
return (r);
}
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