diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-03 14:45:33 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-03 14:45:33 -0700 |
commit | 9dee86896c5968a928e56828236af41c136bdfbd (patch) | |
tree | 0376318b30435785433917be4eb3094f995a6c67 | |
parent | 9ba19ccd2d283a79dd29e8130819c59beca80f62 (diff) | |
parent | d832c0051f4e9cc7d26ef3bc6e9b662bc6a90f3a (diff) |
Merge tag 'objtool-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- Add support for non-rela relocations, in preparation to merge
'recordmcount' functionality into objtool
- Fix assumption that broke under --ffunction-sections (LTO) builds
- Misc cleanups
* tag 'objtool-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Add support for relocations without addends
objtool: Rename rela to reloc
objtool: Use sh_info to find the base for .rela sections
objtool: Do not assume order of parent/child functions
-rw-r--r-- | tools/objtool/arch.h | 2 | ||||
-rw-r--r-- | tools/objtool/arch/x86/decode.c | 2 | ||||
-rw-r--r-- | tools/objtool/check.c | 202 | ||||
-rw-r--r-- | tools/objtool/check.h | 2 | ||||
-rw-r--r-- | tools/objtool/elf.c | 308 | ||||
-rw-r--r-- | tools/objtool/elf.h | 29 | ||||
-rw-r--r-- | tools/objtool/orc_gen.c | 46 | ||||
-rw-r--r-- | tools/objtool/special.c | 28 |
8 files changed, 375 insertions, 244 deletions
diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h index 3c5967748abb..2e2ce089b0e9 100644 --- a/tools/objtool/arch.h +++ b/tools/objtool/arch.h @@ -82,7 +82,7 @@ bool arch_callee_saved_reg(unsigned char reg); unsigned long arch_jump_destination(struct instruction *insn); -unsigned long arch_dest_rela_offset(int addend); +unsigned long arch_dest_reloc_offset(int addend); const char *arch_nop_insn(int len); diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index 9872195f998b..1967370440b3 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -67,7 +67,7 @@ bool arch_callee_saved_reg(unsigned char reg) } } -unsigned long arch_dest_rela_offset(int addend) +unsigned long arch_dest_reloc_offset(int addend) { return addend + 4; } diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 5e0d70a89fb8..e034a8f24f46 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -353,7 +353,7 @@ static struct instruction *find_last_insn(struct objtool_file *file, static int add_dead_ends(struct objtool_file *file) { struct section *sec; - struct rela *rela; + struct reloc *reloc; struct instruction *insn; /* @@ -371,24 +371,24 @@ static int add_dead_ends(struct objtool_file *file) if (!sec) goto reachable; - list_for_each_entry(rela, &sec->rela_list, list) { - if (rela->sym->type != STT_SECTION) { + list_for_each_entry(reloc, &sec->reloc_list, list) { + if (reloc->sym->type != STT_SECTION) { WARN("unexpected relocation symbol type in %s", sec->name); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (insn) insn = list_prev_entry(insn, list); - else if (rela->addend == rela->sym->sec->len) { - insn = find_last_insn(file, rela->sym->sec); + else if (reloc->addend == reloc->sym->sec->len) { + insn = find_last_insn(file, reloc->sym->sec); if (!insn) { WARN("can't find unreachable insn at %s+0x%x", - rela->sym->sec->name, rela->addend); + reloc->sym->sec->name, reloc->addend); return -1; } } else { WARN("can't find unreachable insn at %s+0x%x", - rela->sym->sec->name, rela->addend); + reloc->sym->sec->name, reloc->addend); return -1; } @@ -406,24 +406,24 @@ reachable: if (!sec) return 0; - list_for_each_entry(rela, &sec->rela_list, list) { - if (rela->sym->type != STT_SECTION) { + list_for_each_entry(reloc, &sec->reloc_list, list) { + if (reloc->sym->type != STT_SECTION) { WARN("unexpected relocation symbol type in %s", sec->name); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (insn) insn = list_prev_entry(insn, list); - else if (rela->addend == rela->sym->sec->len) { - insn = find_last_insn(file, rela->sym->sec); + else if (reloc->addend == reloc->sym->sec->len) { + insn = find_last_insn(file, reloc->sym->sec); if (!insn) { WARN("can't find reachable insn at %s+0x%x", - rela->sym->sec->name, rela->addend); + reloc->sym->sec->name, reloc->addend); return -1; } } else { WARN("can't find reachable insn at %s+0x%x", - rela->sym->sec->name, rela->addend); + reloc->sym->sec->name, reloc->addend); return -1; } @@ -441,26 +441,26 @@ static void add_ignores(struct objtool_file *file) struct instruction *insn; struct section *sec; struct symbol *func; - struct rela *rela; + struct reloc *reloc; sec = find_section_by_name(file->elf, ".rela.discard.func_stack_frame_non_standard"); if (!sec) return; - list_for_each_entry(rela, &sec->rela_list, list) { - switch (rela->sym->type) { + list_for_each_entry(reloc, &sec->reloc_list, list) { + switch (reloc->sym->type) { case STT_FUNC: - func = rela->sym; + func = reloc->sym; break; case STT_SECTION: - func = find_func_by_offset(rela->sym->sec, rela->addend); + func = find_func_by_offset(reloc->sym->sec, reloc->addend); if (!func) continue; break; default: - WARN("unexpected relocation symbol type in %s: %d", sec->name, rela->sym->type); + WARN("unexpected relocation symbol type in %s: %d", sec->name, reloc->sym->type); continue; } @@ -580,20 +580,20 @@ static void add_uaccess_safe(struct objtool_file *file) static int add_ignore_alternatives(struct objtool_file *file) { struct section *sec; - struct rela *rela; + struct reloc *reloc; struct instruction *insn; sec = find_section_by_name(file->elf, ".rela.discard.ignore_alts"); if (!sec) return 0; - list_for_each_entry(rela, &sec->rela_list, list) { - if (rela->sym->type != STT_SECTION) { + list_for_each_entry(reloc, &sec->reloc_list, list) { + if (reloc->sym->type != STT_SECTION) { WARN("unexpected relocation symbol type in %s", sec->name); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (!insn) { WARN("bad .discard.ignore_alts entry"); return -1; @@ -611,7 +611,7 @@ static int add_ignore_alternatives(struct objtool_file *file) static int add_jump_destinations(struct objtool_file *file) { struct instruction *insn; - struct rela *rela; + struct reloc *reloc; struct section *dest_sec; unsigned long dest_off; @@ -622,19 +622,19 @@ static int add_jump_destinations(struct objtool_file *file) if (insn->ignore || insn->offset == FAKE_JUMP_OFFSET) continue; - rela = find_rela_by_dest_range(file->elf, insn->sec, + reloc = find_reloc_by_dest_range(file->elf, insn->sec, insn->offset, insn->len); - if (!rela) { + if (!reloc) { dest_sec = insn->sec; dest_off = arch_jump_destination(insn); - } else if (rela->sym->type == STT_SECTION) { - dest_sec = rela->sym->sec; - dest_off = arch_dest_rela_offset(rela->addend); - } else if (rela->sym->sec->idx) { - dest_sec = rela->sym->sec; - dest_off = rela->sym->sym.st_value + - arch_dest_rela_offset(rela->addend); - } else if (strstr(rela->sym->name, "_indirect_thunk_")) { + } else if (reloc->sym->type == STT_SECTION) { + dest_sec = reloc->sym->sec; + dest_off = arch_dest_reloc_offset(reloc->addend); + } else if (reloc->sym->sec->idx) { + dest_sec = reloc->sym->sec; + dest_off = reloc->sym->sym.st_value + + arch_dest_reloc_offset(reloc->addend); + } else if (strstr(reloc->sym->name, "_indirect_thunk_")) { /* * Retpoline jumps are really dynamic jumps in * disguise, so convert them accordingly. @@ -648,7 +648,7 @@ static int add_jump_destinations(struct objtool_file *file) continue; } else { /* external sibling call */ - insn->call_dest = rela->sym; + insn->call_dest = reloc->sym; continue; } @@ -724,15 +724,15 @@ static int add_call_destinations(struct objtool_file *file) { struct instruction *insn; unsigned long dest_off; - struct rela *rela; + struct reloc *reloc; for_each_insn(file, insn) { if (insn->type != INSN_CALL) continue; - rela = find_rela_by_dest_range(file->elf, insn->sec, + reloc = find_reloc_by_dest_range(file->elf, insn->sec, insn->offset, insn->len); - if (!rela) { + if (!reloc) { dest_off = arch_jump_destination(insn); insn->call_dest = find_func_by_offset(insn->sec, dest_off); if (!insn->call_dest) @@ -752,19 +752,19 @@ static int add_call_destinations(struct objtool_file *file) return -1; } - } else if (rela->sym->type == STT_SECTION) { - dest_off = arch_dest_rela_offset(rela->addend); - insn->call_dest = find_func_by_offset(rela->sym->sec, + } else if (reloc->sym->type == STT_SECTION) { + dest_off = arch_dest_reloc_offset(reloc->addend); + insn->call_dest = find_func_by_offset(reloc->sym->sec, dest_off); if (!insn->call_dest) { WARN_FUNC("can't find call dest symbol at %s+0x%lx", insn->sec, insn->offset, - rela->sym->sec->name, + reloc->sym->sec->name, dest_off); return -1; } } else - insn->call_dest = rela->sym; + insn->call_dest = reloc->sym; /* * Many compilers cannot disable KCOV with a function attribute @@ -773,9 +773,9 @@ static int add_call_destinations(struct objtool_file *file) */ if (insn->sec->noinstr && !strncmp(insn->call_dest->name, "__sanitizer_cov_", 16)) { - if (rela) { - rela->type = R_NONE; - elf_write_rela(file->elf, rela); + if (reloc) { + reloc->type = R_NONE; + elf_write_reloc(file->elf, reloc); } elf_write_insn(file->elf, insn->sec, @@ -890,7 +890,7 @@ static int handle_group_alt(struct objtool_file *file, */ if ((insn->offset != special_alt->new_off || (insn->type != INSN_CALL && !is_static_jump(insn))) && - find_rela_by_dest_range(file->elf, insn->sec, insn->offset, insn->len)) { + find_reloc_by_dest_range(file->elf, insn->sec, insn->offset, insn->len)) { WARN_FUNC("unsupported relocation in alternatives section", insn->sec, insn->offset); @@ -1036,34 +1036,34 @@ out: } static int add_jump_table(struct objtool_file *file, struct instruction *insn, - struct rela *table) + struct reloc *table) { - struct rela *rela = table; + struct reloc *reloc = table; struct instruction *dest_insn; struct alternative *alt; struct symbol *pfunc = insn->func->pfunc; unsigned int prev_offset = 0; /* - * Each @rela is a switch table relocation which points to the target + * Each @reloc is a switch table relocation which points to the target * instruction. */ - list_for_each_entry_from(rela, &table->sec->rela_list, list) { + list_for_each_entry_from(reloc, &table->sec->reloc_list, list) { /* Check for the end of the table: */ - if (rela != table && rela->jump_table_start) + if (reloc != table && reloc->jump_table_start) break; /* Make sure the table entries are consecutive: */ - if (prev_offset && rela->offset != prev_offset + 8) + if (prev_offset && reloc->offset != prev_offset + 8) break; /* Detect function pointers from contiguous objects: */ - if (rela->sym->sec == pfunc->sec && - rela->addend == pfunc->offset) + if (reloc->sym->sec == pfunc->sec && + reloc->addend == pfunc->offset) break; - dest_insn = find_insn(file, rela->sym->sec, rela->addend); + dest_insn = find_insn(file, reloc->sym->sec, reloc->addend); if (!dest_insn) break; @@ -1079,7 +1079,7 @@ static int add_jump_table(struct objtool_file *file, struct instruction *insn, alt->insn = dest_insn; list_add_tail(&alt->list, &insn->alts); - prev_offset = rela->offset; + prev_offset = reloc->offset; } if (!prev_offset) { @@ -1134,11 +1134,11 @@ static int add_jump_table(struct objtool_file *file, struct instruction *insn, * * NOTE: RETPOLINE made it harder still to decode dynamic jumps. */ -static struct rela *find_jump_table(struct objtool_file *file, +static struct reloc *find_jump_table(struct objtool_file *file, struct symbol *func, struct instruction *insn) { - struct rela *text_rela, *table_rela; + struct reloc *text_reloc, *table_reloc; struct instruction *dest_insn, *orig_insn = insn; struct section *table_sec; unsigned long table_offset; @@ -1163,16 +1163,16 @@ static struct rela *find_jump_table(struct objtool_file *file, break; /* look for a relocation which references .rodata */ - text_rela = find_rela_by_dest_range(file->elf, insn->sec, + text_reloc = find_reloc_by_dest_range(file->elf, insn->sec, insn->offset, insn->len); - if (!text_rela || text_rela->sym->type != STT_SECTION || - !text_rela->sym->sec->rodata) + if (!text_reloc || text_reloc->sym->type != STT_SECTION || + !text_reloc->sym->sec->rodata) continue; - table_offset = text_rela->addend; - table_sec = text_rela->sym->sec; + table_offset = text_reloc->addend; + table_sec = text_reloc->sym->sec; - if (text_rela->type == R_X86_64_PC32) + if (text_reloc->type == R_X86_64_PC32) table_offset += 4; /* @@ -1189,14 +1189,14 @@ static struct rela *find_jump_table(struct objtool_file *file, continue; /* - * Each table entry has a rela associated with it. The rela + * Each table entry has a reloc associated with it. The reloc * should reference text in the same function as the original * instruction. */ - table_rela = find_rela_by_dest(file->elf, table_sec, table_offset); - if (!table_rela) + table_reloc = find_reloc_by_dest(file->elf, table_sec, table_offset); + if (!table_reloc) continue; - dest_insn = find_insn(file, table_rela->sym->sec, table_rela->addend); + dest_insn = find_insn(file, table_reloc->sym->sec, table_reloc->addend); if (!dest_insn || !dest_insn->func || dest_insn->func->pfunc != func) continue; @@ -1205,10 +1205,10 @@ static struct rela *find_jump_table(struct objtool_file *file, * indicates a rare GCC quirk/bug which can leave dead code * behind. */ - if (text_rela->type == R_X86_64_PC32) + if (text_reloc->type == R_X86_64_PC32) file->ignore_unreachables = true; - return table_rela; + return table_reloc; } return NULL; @@ -1222,7 +1222,7 @@ static void mark_func_jump_tables(struct objtool_file *file, struct symbol *func) { struct instruction *insn, *last = NULL; - struct rela *rela; + struct reloc *reloc; func_for_each_insn(file, func, insn) { if (!last) @@ -1245,10 +1245,10 @@ static void mark_func_jump_tables(struct objtool_file *file, if (insn->type != INSN_JUMP_DYNAMIC) continue; - rela = find_jump_table(file, func, insn); - if (rela) { - rela->jump_table_start = true; - insn->jump_table = rela; + reloc = find_jump_table(file, func, insn); + if (reloc) { + reloc->jump_table_start = true; + insn->jump_table = reloc; } } } @@ -1302,8 +1302,8 @@ static int add_jump_table_alts(struct objtool_file *file) static int read_unwind_hints(struct objtool_file *file) { - struct section *sec, *relasec; - struct rela *rela; + struct section *sec, *relocsec; + struct reloc *reloc; struct unwind_hint *hint; struct instruction *insn; struct cfi_reg *cfa; @@ -1313,8 +1313,8 @@ static int read_unwind_hints(struct objtool_file *file) if (!sec) return 0; - relasec = sec->rela; - if (!relasec) { + relocsec = sec->reloc; + if (!relocsec) { WARN("missing .rela.discard.unwind_hints section"); return -1; } @@ -1329,13 +1329,13 @@ static int read_unwind_hints(struct objtool_file *file) for (i = 0; i < sec->len / sizeof(struct unwind_hint); i++) { hint = (struct unwind_hint *)sec->data->d_buf + i; - rela = find_rela_by_dest(file->elf, sec, i * sizeof(*hint)); - if (!rela) { - WARN("can't find rela for unwind_hints[%d]", i); + reloc = find_reloc_by_dest(file->elf, sec, i * sizeof(*hint)); + if (!reloc) { + WARN("can't find reloc for unwind_hints[%d]", i); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (!insn) { WARN("can't find insn for unwind_hints[%d]", i); return -1; @@ -1393,19 +1393,19 @@ static int read_retpoline_hints(struct objtool_file *file) { struct section *sec; struct instruction *insn; - struct rela *rela; + struct reloc *reloc; sec = find_section_by_name(file->elf, ".rela.discard.retpoline_safe"); if (!sec) return 0; - list_for_each_entry(rela, &sec->rela_list, list) { - if (rela->sym->type != STT_SECTION) { + list_for_each_entry(reloc, &sec->reloc_list, list) { + if (reloc->sym->type != STT_SECTION) { WARN("unexpected relocation symbol type in %s", sec->name); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (!insn) { WARN("bad .discard.retpoline_safe entry"); return -1; @@ -1428,19 +1428,19 @@ static int read_instr_hints(struct objtool_file *file) { struct section *sec; struct instruction *insn; - struct rela *rela; + struct reloc *reloc; sec = find_section_by_name(file->elf, ".rela.discard.instr_end"); if (!sec) return 0; - list_for_each_entry(rela, &sec->rela_list, list) { - if (rela->sym->type != STT_SECTION) { + list_for_each_entry(reloc, &sec->reloc_list, list) { + if (reloc->sym->type != STT_SECTION) { WARN("unexpected relocation symbol type in %s", sec->name); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (!insn) { WARN("bad .discard.instr_end entry"); return -1; @@ -1453,13 +1453,13 @@ static int read_instr_hints(struct objtool_file *file) if (!sec) return 0; - list_for_each_entry(rela, &sec->rela_list, list) { - if (rela->sym->type != STT_SECTION) { + list_for_each_entry(reloc, &sec->reloc_list, list) { + if (reloc->sym->type != STT_SECTION) { WARN("unexpected relocation symbol type in %s", sec->name); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (!insn) { WARN("bad .discard.instr_begin entry"); return -1; @@ -1475,22 +1475,22 @@ static int read_intra_function_calls(struct objtool_file *file) { struct instruction *insn; struct section *sec; - struct rela *rela; + struct reloc *reloc; sec = find_section_by_name(file->elf, ".rela.discard.intra_function_calls"); if (!sec) return 0; - list_for_each_entry(rela, &sec->rela_list, list) { + list_for_each_entry(reloc, &sec->reloc_list, list) { unsigned long dest_off; - if (rela->sym->type != STT_SECTION) { + if (reloc->sym->type != STT_SECTION) { WARN("unexpected relocation symbol type in %s", sec->name); return -1; } - insn = find_insn(file, rela->sym->sec, rela->addend); + insn = find_insn(file, reloc->sym->sec, reloc->addend); if (!insn) { WARN("bad .discard.intra_function_call entry"); return -1; diff --git a/tools/objtool/check.h b/tools/objtool/check.h index 906b5210f7ca..061aa96e15d3 100644 --- a/tools/objtool/check.h +++ b/tools/objtool/check.h @@ -37,7 +37,7 @@ struct instruction { struct symbol *call_dest; struct instruction *jump_dest; struct instruction *first_jump_src; - struct rela *jump_table; + struct reloc *jump_table; struct list_head alts; struct symbol *func; struct list_head stack_ops; diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index 26d11d821941..3ddbd66f1a37 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -228,26 +228,26 @@ struct symbol *find_symbol_by_name(const struct elf *elf, const char *name) return NULL; } -struct rela *find_rela_by_dest_range(const struct elf *elf, struct section *sec, +struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *sec, unsigned long offset, unsigned int len) { - struct rela *rela, *r = NULL; + struct reloc *reloc, *r = NULL; unsigned long o; - if (!sec->rela) + if (!sec->reloc) return NULL; - sec = sec->rela; + sec = sec->reloc; for_offset_range(o, offset, offset + len) { - elf_hash_for_each_possible(elf->rela_hash, rela, hash, + elf_hash_for_each_possible(elf->reloc_hash, reloc, hash, sec_offset_hash(sec, o)) { - if (rela->sec != sec) + if (reloc->sec != sec) continue; - if (rela->offset >= offset && rela->offset < offset + len) { - if (!r || rela->offset < r->offset) - r = rela; + if (reloc->offset >= offset && reloc->offset < offset + len) { + if (!r || reloc->offset < r->offset) + r = reloc; } } if (r) @@ -257,9 +257,9 @@ struct rela *find_rela_by_dest_range(const struct elf *elf, struct section *sec, return NULL; } -struct rela *find_rela_by_dest(const struct elf *elf, struct section *sec, unsigned long offset) +struct reloc *find_reloc_by_dest(const struct elf *elf, struct section *sec, unsigned long offset) { - return find_rela_by_dest_range(elf, sec, offset, 1); + return find_reloc_by_dest_range(elf, sec, offset, 1); } static int read_sections(struct elf *elf) @@ -288,7 +288,7 @@ static int read_sections(struct elf *elf) memset(sec, 0, sizeof(*sec)); INIT_LIST_HEAD(&sec->symbol_list); - INIT_LIST_HEAD(&sec->rela_list); + INIT_LIST_HEAD(&sec->reloc_list); s = elf_getscn(elf->elf, i); if (!s) { @@ -434,7 +434,13 @@ static int read_symbols(struct elf *elf) size_t pnamelen; if (sym->type != STT_FUNC) continue; - sym->pfunc = sym->cfunc = sym; + + if (sym->pfunc == NULL) + sym->pfunc = sym; + + if (sym->cfunc == NULL) + sym->cfunc = sym; + coldstr = strstr(sym->name, ".cold"); if (!coldstr) continue; @@ -482,72 +488,101 @@ err: return -1; } -void elf_add_rela(struct elf *elf, struct rela *rela) +void elf_add_reloc(struct elf *elf, struct reloc *reloc) +{ + struct section *sec = reloc->sec; + + list_add_tail(&reloc->list, &sec->reloc_list); + elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc)); +} + +static int read_rel_reloc(struct section *sec, int i, struct reloc *reloc, unsigned int *symndx) { - struct section *sec = rela->sec; + if (!gelf_getrel(sec->data, i, &reloc->rel)) { + WARN_ELF("gelf_getrel"); + return -1; + } + reloc->type = GELF_R_TYPE(reloc->rel.r_info); + reloc->addend = 0; + reloc->offset = reloc->rel.r_offset; + *symndx = GELF_R_SYM(reloc->rel.r_info); + return 0; +} - list_add_tail(&rela->list, &sec->rela_list); - elf_hash_add(elf->rela_hash, &rela->hash, rela_hash(rela)); +static int read_rela_reloc(struct section *sec, int i, struct reloc *reloc, unsigned int *symndx) +{ + if (!gelf_getrela(sec->data, i, &reloc->rela)) { + WARN_ELF("gelf_getrela"); + return -1; + } + reloc->type = GELF_R_TYPE(reloc->rela.r_info); + reloc->addend = reloc->rela.r_addend; + reloc->offset = reloc->rela.r_offset; + *symndx = GELF_R_SYM(reloc->rela.r_info); + return 0; } -static int read_relas(struct elf *elf) +static int read_relocs(struct elf *elf) { struct section *sec; - struct rela *rela; + struct reloc *reloc; int i; unsigned int symndx; - unsigned long nr_rela, max_rela = 0, tot_rela = 0; + unsigned long nr_reloc, max_reloc = 0, tot_reloc = 0; list_for_each_entry(sec, &elf->sections, list) { - if (sec->sh.sh_type != SHT_RELA) + if ((sec->sh.sh_type != SHT_RELA) && + (sec->sh.sh_type != SHT_REL)) continue; - sec->base = find_section_by_name(elf, sec->name + 5); + sec->base = find_section_by_index(elf, sec->sh.sh_info); if (!sec->base) { - WARN("can't find base section for rela section %s", + WARN("can't find base section for reloc section %s", sec->name); return -1; } - sec->base->rela = sec; + sec->base->reloc = sec; - nr_rela = 0; + nr_reloc = 0; for (i = 0; i < sec->sh.sh_size / sec->sh.sh_entsize; i++) { - rela = malloc(sizeof(*rela)); - if (!rela) { + reloc = malloc(sizeof(*reloc)); + if (!reloc) { perror("malloc"); return -1; } - memset(rela, 0, sizeof(*rela)); - - if (!gelf_getrela(sec->data, i, &rela->rela)) { - WARN_ELF("gelf_getrela"); - return -1; + memset(reloc, 0, sizeof(*reloc)); + switch (sec->sh.sh_type) { + case SHT_REL: + if (read_rel_reloc(sec, i, reloc, &symndx)) + return -1; + break; + case SHT_RELA: + if (read_rela_reloc(sec, i, reloc, &symndx)) + return -1; + break; + default: return -1; } - rela->type = GELF_R_TYPE(rela->rela.r_info); - rela->addend = rela->rela.r_addend; - rela->offset = rela->rela.r_offset; - symndx = GELF_R_SYM(rela->rela.r_info); - rela->sec = sec; - rela->idx = i; - rela->sym = find_symbol_by_index(elf, symndx); - if (!rela->sym) { - WARN("can't find rela entry symbol %d for %s", + reloc->sec = sec; + reloc->idx = i; + reloc->sym = find_symbol_by_index(elf, symndx); + if (!reloc->sym) { + WARN("can't find reloc entry symbol %d for %s", symndx, sec->name); return -1; } - elf_add_rela(elf, rela); - nr_rela++; + elf_add_reloc(elf, reloc); + nr_reloc++; } - max_rela = max(max_rela, nr_rela); - tot_rela += nr_rela; + max_reloc = max(max_reloc, nr_reloc); + tot_reloc += nr_reloc; } if (stats) { - printf("max_rela: %lu\n", max_rela); - printf("tot_rela: %lu\n", tot_rela); + printf("max_reloc: %lu\n", max_reloc); + printf("tot_reloc: %lu\n", tot_reloc); } return 0; @@ -573,7 +608,7 @@ struct elf *elf_open_read(const char *name, int flags) elf_hash_init(elf->symbol_name_hash); elf_hash_init(elf->section_hash); elf_hash_init(elf->section_name_hash); - elf_hash_init(elf->rela_hash); + elf_hash_init(elf->reloc_hash); elf->fd = open(name, flags); if (elf->fd == -1) { @@ -606,7 +641,7 @@ struct elf *elf_open_read(const char *name, int flags) if (read_symbols(elf)) goto err; - if (read_relas(elf)) + if (read_relocs(elf)) goto err; return elf; @@ -632,7 +667,7 @@ struct section *elf_create_section(struct elf *elf, const char *name, memset(sec, 0, sizeof(*sec)); INIT_LIST_HEAD(&sec->symbol_list); - INIT_LIST_HEAD(&sec->rela_list); + INIT_LIST_HEAD(&sec->reloc_list); s = elf_newscn(elf->elf); if (!s) { @@ -719,28 +754,28 @@ struct section *elf_create_section(struct elf *elf, const char *name, return sec; } -struct section *elf_create_rela_section(struct elf *elf, struct section *base) +static struct section *elf_create_rel_reloc_section(struct elf *elf, struct section *base) { - char *relaname; + char *relocname; struct section *sec; - relaname = malloc(strlen(base->name) + strlen(".rela") + 1); - if (!relaname) { + relocname = malloc(strlen(base->name) + strlen(".rel") + 1); + if (!relocname) { perror("malloc"); return NULL; } - strcpy(relaname, ".rela"); - strcat(relaname, base->name); + strcpy(relocname, ".rel"); + strcat(relocname, base->name); - sec = elf_create_section(elf, relaname, sizeof(GElf_Rela), 0); - free(relaname); + sec = elf_create_section(elf, relocname, sizeof(GElf_Rel), 0); + free(relocname); if (!sec) return NULL; - base->rela = sec; + base->reloc = sec; sec->base = base; - sec->sh.sh_type = SHT_RELA; + sec->sh.sh_type = SHT_REL; sec->sh.sh_addralign = 8; sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx; sec->sh.sh_info = base->idx; @@ -749,42 +784,125 @@ struct section *elf_create_rela_section(struct elf *elf, struct section *base) return sec; } -int elf_rebuild_rela_section(struct elf *elf, struct section *sec) +static struct section *elf_create_rela_reloc_section(struct elf *elf, struct section *base) { - struct rela *rela; - int nr, idx = 0, size; - GElf_Rela *relas; + char *relocname; + struct section *sec; - nr = 0; - list_for_each_entry(rela, &sec->rela_list, list) - nr++; + relocname = malloc(strlen(base->name) + strlen(".rela") + 1); + if (!relocname) { + perror("malloc"); + return NULL; + } + strcpy(relocname, ".rela"); + strcat(relocname, base->name); + + sec = elf_create_section(elf, relocname, sizeof(GElf_Rela), 0); + free(relocname); + if (!sec) + return NULL; - size = nr * sizeof(*relas); - relas = malloc(size); - if (!relas) { + base->reloc = sec; + sec->base = base; + + sec->sh.sh_type = SHT_RELA; + sec->sh.sh_addralign = 8; + sec->sh.sh_link = find_section_by_name(elf, ".symtab")->idx; + sec->sh.sh_info = base->idx; + sec->sh.sh_flags = SHF_INFO_LINK; + + return sec; +} + +struct section *elf_create_reloc_section(struct elf *elf, + struct section *base, + int reltype) +{ + switch (reltype) { + case SHT_REL: return elf_create_rel_reloc_section(elf, base); + case SHT_RELA: return elf_create_rela_reloc_section(elf, base); + default: return NULL; + } +} + +static int elf_rebuild_rel_reloc_section(struct section *sec, int nr) +{ + struct reloc *reloc; + int idx = 0, size; + GElf_Rel *relocs; + + /* Allocate a buffer for relocations */ + size = nr * sizeof(*relocs); + relocs = malloc(size); + if (!relocs) { perror("malloc"); return -1; } - sec->changed = true; - elf->changed = true; + sec->data->d_buf = relocs; + sec->data->d_size = size; + + sec->sh.sh_size = size; + + idx = 0; + list_for_each_entry(reloc, &sec->reloc_list, list) { + relocs[idx].r_offset = reloc->offset; + relocs[idx].r_info = GELF_R_INFO(reloc->sym->idx, reloc->type); + idx++; + } + + return 0; +} + +static int elf_rebuild_rela_reloc_section(struct section *sec, int nr) +{ + struct reloc *reloc; + int idx = 0, size; + GElf_Rela *relocs; + + /* Allocate a buffer for relocations with addends */ + size = nr * sizeof(*relocs); + relocs = malloc(size); + if (!relocs) { + perror("malloc"); + return -1; + } - sec->data->d_buf = relas; + sec->data->d_buf = relocs; sec->data->d_size = size; sec->sh.sh_size = size; idx = 0; - list_for_each_entry(rela, &sec->rela_list, list) { - relas[idx].r_offset = rela->offset; - relas[idx].r_addend = rela->addend; - relas[idx].r_info = GELF_R_INFO(rela->sym->idx, rela->type); + list_for_each_entry(reloc, &sec->reloc_list, list) { + relocs[idx].r_offset = reloc->offset; + relocs[idx].r_addend = reloc->addend; + relocs[idx].r_info = GELF_R_INFO(reloc->sym->idx, reloc->type); idx++; } return 0; } +int elf_rebuild_reloc_section(struct elf *elf, struct section *sec) +{ + struct reloc *reloc; + int nr; + + sec->changed = true; + elf->changed = true; + + 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); + default: return -1; + } +} + int elf_write_insn(struct elf *elf, struct section *sec, unsigned long offset, unsigned int len, const char *insn) @@ -804,17 +922,27 @@ int elf_write_insn(struct elf *elf, struct section *sec, return 0; } -int elf_write_rela(struct elf *elf, struct rela *rela) +int elf_write_reloc(struct elf *elf, struct reloc *reloc) { - struct section *sec = rela->sec; + struct section *sec = reloc->sec; - rela->rela.r_info = GELF_R_INFO(rela->sym->idx, rela->type); - rela->rela.r_addend = rela->addend; - rela->rela.r_offset = rela->offset; + if (sec->sh.sh_type == SHT_REL) { + reloc->rel.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type); + reloc->rel.r_offset = reloc->offset; - if (!gelf_update_rela(sec->data, rela->idx, &rela->rela)) { |