diff options
| -rw-r--r-- | tools/objtool/builtin-check.c | 11 | ||||
| -rw-r--r-- | tools/objtool/builtin.h | 2 | ||||
| -rw-r--r-- | tools/objtool/check.c | 98 | ||||
| -rw-r--r-- | tools/objtool/check.h | 3 | ||||
| -rw-r--r-- | tools/objtool/elf.h | 2 |
5 files changed, 112 insertions, 4 deletions
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index 10fbe75ab43d..be42b716166b 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -14,10 +14,11 @@ */ #include <subcmd/parse-options.h> +#include <string.h> #include "builtin.h" #include "check.h" -bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats; +bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux; static const char * const check_usage[] = { "objtool check [<options>] file.o", @@ -32,12 +33,14 @@ const struct option check_options[] = { OPT_BOOLEAN('b', "backtrace", &backtrace, "unwind on error"), OPT_BOOLEAN('a', "uaccess", &uaccess, "enable uaccess checking"), OPT_BOOLEAN('s', "stats", &stats, "print statistics"), + OPT_BOOLEAN('d', "duplicate", &validate_dup, "duplicate validation for vmlinux.o"), + OPT_BOOLEAN('l', "vmlinux", &vmlinux, "vmlinux.o validation"), OPT_END(), }; int cmd_check(int argc, const char **argv) { - const char *objname; + const char *objname, *s; argc = parse_options(argc, argv, check_options, check_usage, 0); @@ -46,5 +49,9 @@ int cmd_check(int argc, const char **argv) objname = argv[0]; + s = strstr(objname, "vmlinux.o"); + if (s && !s[9]) + vmlinux = true; + return check(objname, false); } diff --git a/tools/objtool/builtin.h b/tools/objtool/builtin.h index 0b907902ee79..85c979caa367 100644 --- a/tools/objtool/builtin.h +++ b/tools/objtool/builtin.h @@ -8,7 +8,7 @@ #include <subcmd/parse-options.h> extern const struct option check_options[]; -extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats; +extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux; extern int cmd_check(int argc, const char **argv); extern int cmd_orc(int argc, const char **argv); diff --git a/tools/objtool/check.c b/tools/objtool/check.c index abf97159bf1e..87e528c2840c 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -257,6 +257,9 @@ static int decode_instructions(struct objtool_file *file) strncmp(sec->name, ".discard.", 9)) sec->text = true; + if (!strcmp(sec->name, ".noinstr.text")) + sec->noinstr = true; + for (offset = 0; offset < sec->len; offset += insn->len) { insn = malloc(sizeof(*insn)); if (!insn) { @@ -1340,6 +1343,53 @@ static int read_retpoline_hints(struct objtool_file *file) return 0; } +static int read_instr_hints(struct objtool_file *file) +{ + struct section *sec; + struct instruction *insn; + struct rela *rela; + + 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) { + WARN("unexpected relocation symbol type in %s", sec->name); + return -1; + } + + insn = find_insn(file, rela->sym->sec, rela->addend); + if (!insn) { + WARN("bad .discard.instr_end entry"); + return -1; + } + + insn->instr--; + } + + sec = find_section_by_name(file->elf, ".rela.discard.instr_begin"); + if (!sec) + return 0; + + list_for_each_entry(rela, &sec->rela_list, list) { + if (rela->sym->type != STT_SECTION) { + WARN("unexpected relocation symbol type in %s", sec->name); + return -1; + } + + insn = find_insn(file, rela->sym->sec, rela->addend); + if (!insn) { + WARN("bad .discard.instr_begin entry"); + return -1; + } + + insn->instr++; + } + + return 0; +} + static void mark_rodata(struct objtool_file *file) { struct section *sec; @@ -1411,6 +1461,10 @@ static int decode_sections(struct objtool_file *file) if (ret) return ret; + ret = read_instr_hints(file); + if (ret) + return ret; + return 0; } @@ -2007,6 +2061,13 @@ static inline const char *call_dest_name(struct instruction *insn) static int validate_call(struct instruction *insn, struct insn_state *state) { + if (state->noinstr && state->instr <= 0 && + (!insn->call_dest || insn->call_dest->sec != insn->sec)) { + WARN_FUNC("call to %s() leaves .noinstr.text section", + insn->sec, insn->offset, call_dest_name(insn)); + return 1; + } + if (state->uaccess && !func_uaccess_safe(insn->call_dest)) { WARN_FUNC("call to %s() with UACCESS enabled", insn->sec, insn->offset, call_dest_name(insn)); @@ -2035,6 +2096,12 @@ static int validate_sibling_call(struct instruction *insn, struct insn_state *st static int validate_return(struct symbol *func, struct instruction *insn, struct insn_state *state) { + if (state->noinstr && state->instr > 0) { + WARN_FUNC("return with instrumentation enabled", + insn->sec, insn->offset); + return 1; + } + if (state->uaccess && !func_uaccess_safe(func)) { WARN_FUNC("return with UACCESS enabled", insn->sec, insn->offset); @@ -2115,6 +2182,9 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, return 0; } + if (state.noinstr) + state.instr += insn->instr; + if (insn->hint) state.cfi = insn->cfi; else @@ -2422,6 +2492,14 @@ static int validate_section(struct objtool_file *file, struct section *sec) struct insn_state state; int ret, warnings = 0; + /* + * We need the full vmlinux for noinstr validation, otherwise we can + * not correctly determine insn->call_dest->sec (external symbols do + * not have a section). + */ + if (vmlinux) + state.noinstr = sec->noinstr; + list_for_each_entry(func, &sec->symbol_list, list) { if (func->type != STT_FUNC) continue; @@ -2456,6 +2534,17 @@ static int validate_section(struct objtool_file *file, struct section *sec) return warnings; } +static int validate_vmlinux_functions(struct objtool_file *file) +{ + struct section *sec; + + sec = find_section_by_name(file->elf, ".noinstr.text"); + if (!sec) + return 0; + + return validate_section(file, sec); +} + static int validate_functions(struct objtool_file *file) { struct section *sec; @@ -2513,6 +2602,15 @@ int check(const char *_objname, bool orc) if (list_empty(&file.insn_list)) goto out; + if (vmlinux && !validate_dup) { + ret = validate_vmlinux_functions(&file); + if (ret < 0) + goto out; + + warnings += ret; + goto out; + } + if (retpoline) { ret = validate_retpoline(&file); if (ret < 0) diff --git a/tools/objtool/check.h b/tools/objtool/check.h index 99413d4ca4b1..12a9660c960b 100644 --- a/tools/objtool/check.h +++ b/tools/objtool/check.h @@ -18,6 +18,8 @@ struct insn_state { unsigned int uaccess_stack; bool uaccess; bool df; + bool noinstr; + s8 instr; }; struct instruction { @@ -31,6 +33,7 @@ struct instruction { bool alt_group, dead_end, ignore, ignore_alts; bool hint; bool retpoline_safe; + s8 instr; u8 visited; u8 ret_offset; struct symbol *call_dest; diff --git a/tools/objtool/elf.h b/tools/objtool/elf.h index 0b79c2353a21..eb79cb999209 100644 --- a/tools/objtool/elf.h +++ b/tools/objtool/elf.h @@ -39,7 +39,7 @@ struct section { char *name; int idx; unsigned int len; - bool changed, text, rodata; + bool changed, text, rodata, noinstr; }; struct symbol { |