diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-11-19 13:27:52 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-11-19 13:27:52 -0800 |
commit | 9d7d4ad222aea8ab482e78858d03b10221c7fe78 (patch) | |
tree | b2e29edb5e4cdda157f629295cae0aaf1efab94f /tools | |
parent | 364eeb79a213fcf9164208b53764223ad522d6b3 (diff) | |
parent | d5173f7537505315557d8580e3a648f07f17deda (diff) |
Merge tag 'objtool-core-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- Detect non-relocated text references for more robust
IBT sealing (Josh Poimboeuf)
- Fix build error when building stripped down
UAPI headers (HONG Yifan)
- Exclude __tracepoints data from ENDBR checks to fix
false positives on clang builds (Peter Zijlstra)
- Fix ORC unwind for newly forked tasks (Zheng Yejian)
- Fix readelf related faddr2line regression (Carlos Llamas)
* tag 'objtool-core-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Exclude __tracepoints data from ENDBR checks
Revert "scripts/faddr2line: Check only two symbols when calculating symbol size"
x86/unwind/orc: Fix unwind for newly forked tasks
objtool: Also include tools/include/uapi
objtool: Detect non-relocated text references
Diffstat (limited to 'tools')
-rw-r--r-- | tools/objtool/Makefile | 1 | ||||
-rw-r--r-- | tools/objtool/arch/x86/decode.c | 15 | ||||
-rw-r--r-- | tools/objtool/check.c | 113 | ||||
-rw-r--r-- | tools/objtool/include/objtool/arch.h | 1 |
4 files changed, 77 insertions, 53 deletions
diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile index bf7f7f84ac62..f56e27727534 100644 --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -24,6 +24,7 @@ LIBELF_LIBS := $(shell $(HOSTPKG_CONFIG) libelf --libs 2>/dev/null || echo -lel all: $(OBJTOOL) INCLUDES := -I$(srctree)/tools/include \ + -I$(srctree)/tools/include/uapi \ -I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \ -I$(srctree)/tools/arch/$(SRCARCH)/include \ -I$(srctree)/tools/objtool/include \ diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index ed6bff0e01dc..fe1362c34564 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -456,10 +456,6 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec if (!rex_w) break; - /* skip RIP relative displacement */ - if (is_RIP()) - break; - /* skip nontrivial SIB */ if (have_SIB()) { modrm_rm = sib_base; @@ -467,6 +463,12 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec break; } + /* lea disp(%rip), %dst */ + if (is_RIP()) { + insn->type = INSN_LEA_RIP; + break; + } + /* lea disp(%src), %dst */ ADD_OP(op) { op->src.offset = ins.displacement.value; @@ -737,7 +739,10 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec break; } - insn->immediate = ins.immediate.nbytes ? ins.immediate.value : 0; + if (ins.immediate.nbytes) + insn->immediate = ins.immediate.value; + else if (ins.displacement.nbytes) + insn->immediate = ins.displacement.value; return 0; } diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 6604f5d038aa..f7586f82b967 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -4392,6 +4392,51 @@ static bool noendbr_range(struct objtool_file *file, struct instruction *insn) return insn->offset == sym->offset + sym->len; } +static int __validate_ibt_insn(struct objtool_file *file, struct instruction *insn, + struct instruction *dest) +{ + if (dest->type == INSN_ENDBR) { + mark_endbr_used(dest); + return 0; + } + + if (insn_func(dest) && insn_func(insn) && + insn_func(dest)->pfunc == insn_func(insn)->pfunc) { + /* + * Anything from->to self is either _THIS_IP_ or + * IRET-to-self. + * + * There is no sane way to annotate _THIS_IP_ since the + * compiler treats the relocation as a constant and is + * happy to fold in offsets, skewing any annotation we + * do, leading to vast amounts of false-positives. + * + * There's also compiler generated _THIS_IP_ through + * KCOV and such which we have no hope of annotating. + * + * As such, blanket accept self-references without + * issue. + */ + return 0; + } + + /* + * Accept anything ANNOTATE_NOENDBR. + */ + if (dest->noendbr) + return 0; + + /* + * Accept if this is the instruction after a symbol + * that is (no)endbr -- typical code-range usage. + */ + if (noendbr_range(file, dest)) + return 0; + + WARN_INSN(insn, "relocation to !ENDBR: %s", offstr(dest->sec, dest->offset)); + return 1; +} + static int validate_ibt_insn(struct objtool_file *file, struct instruction *insn) { struct instruction *dest; @@ -4404,6 +4449,7 @@ static int validate_ibt_insn(struct objtool_file *file, struct instruction *insn * direct/indirect branches: */ switch (insn->type) { + case INSN_CALL: case INSN_CALL_DYNAMIC: case INSN_JUMP_CONDITIONAL: @@ -4413,6 +4459,23 @@ static int validate_ibt_insn(struct objtool_file *file, struct instruction *insn case INSN_RETURN: case INSN_NOP: return 0; + + case INSN_LEA_RIP: + if (!insn_reloc(file, insn)) { + /* local function pointer reference without reloc */ + + off = arch_jump_destination(insn); + + dest = find_insn(file, insn->sec, off); + if (!dest) { + WARN_INSN(insn, "corrupt function pointer reference"); + return 1; + } + + return __validate_ibt_insn(file, insn, dest); + } + break; + default: break; } @@ -4423,13 +4486,6 @@ static int validate_ibt_insn(struct objtool_file *file, struct instruction *insn reloc_offset(reloc) + 1, (insn->offset + insn->len) - (reloc_offset(reloc) + 1))) { - /* - * static_call_update() references the trampoline, which - * doesn't have (or need) ENDBR. Skip warning in that case. - */ - if (reloc->sym->static_call_tramp) - continue; - off = reloc->sym->offset; if (reloc_type(reloc) == R_X86_64_PC32 || reloc_type(reloc) == R_X86_64_PLT32) @@ -4441,47 +4497,7 @@ static int validate_ibt_insn(struct objtool_file *file, struct instruction *insn if (!dest) continue; - if (dest->type == INSN_ENDBR) { - mark_endbr_used(dest); - continue; - } - - if (insn_func(dest) && insn_func(insn) && - insn_func(dest)->pfunc == insn_func(insn)->pfunc) { - /* - * Anything from->to self is either _THIS_IP_ or - * IRET-to-self. - * - * There is no sane way to annotate _THIS_IP_ since the - * compiler treats the relocation as a constant and is - * happy to fold in offsets, skewing any annotation we - * do, leading to vast amounts of false-positives. - * - * There's also compiler generated _THIS_IP_ through - * KCOV and such which we have no hope of annotating. - * - * As such, blanket accept self-references without - * issue. - */ - continue; - } - - /* - * Accept anything ANNOTATE_NOENDBR. - */ - if (dest->noendbr) - continue; - - /* - * Accept if this is the instruction after a symbol - * that is (no)endbr -- typical code-range usage. - */ - if (noendbr_range(file, dest)) - continue; - - WARN_INSN(insn, "relocation to !ENDBR: %s", offstr(dest->sec, dest->offset)); - - warnings++; + warnings += __validate_ibt_insn(file, insn, dest); } return warnings; @@ -4557,6 +4573,7 @@ static int validate_ibt(struct objtool_file *file) !strcmp(sec->name, "__jump_table") || !strcmp(sec->name, "__mcount_loc") || !strcmp(sec->name, ".kcfi_traps") || + !strcmp(sec->name, "__tracepoints") || strstr(sec->name, "__patchable_function_entries")) continue; diff --git a/tools/objtool/include/objtool/arch.h b/tools/objtool/include/objtool/arch.h index 0b303eba660e..d63b46a19f39 100644 --- a/tools/objtool/include/objtool/arch.h +++ b/tools/objtool/include/objtool/arch.h @@ -28,6 +28,7 @@ enum insn_type { INSN_CLD, INSN_TRAP, INSN_ENDBR, + INSN_LEA_RIP, INSN_OTHER, }; |