diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2022-06-27 22:21:17 +0000 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-06-29 17:43:41 +0200 |
| commit | f43b9876e857c739d407bc56df288b0ebe1a9164 (patch) | |
| tree | 22fcf2716b615556869c460a71ed3fd9b1393bd6 /tools/objtool | |
| parent | 26aae8ccbc1972233afd08fb3f368947c0314265 (diff) | |
| download | linux-f43b9876e857c739d407bc56df288b0ebe1a9164.tar.gz | |
x86/retbleed: Add fine grained Kconfig knobs
Do fine-grained Kconfig for all the various retbleed parts.
NOTE: if your compiler doesn't support return thunks this will
silently 'upgrade' your mitigation to IBPB, you might not like this.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/builtin-check.c | 7 | ||||
| -rw-r--r-- | tools/objtool/check.c | 9 | ||||
| -rw-r--r-- | tools/objtool/include/objtool/builtin.h | 1 |
3 files changed, 15 insertions, 2 deletions
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index c063e1ff96b2f..24fbe803a0d32 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -68,6 +68,7 @@ const struct option check_options[] = { OPT_BOOLEAN('n', "noinstr", &opts.noinstr, "validate noinstr rules"), OPT_BOOLEAN('o', "orc", &opts.orc, "generate ORC metadata"), OPT_BOOLEAN('r', "retpoline", &opts.retpoline, "validate and annotate retpoline usage"), + OPT_BOOLEAN(0, "rethunk", &opts.rethunk, "validate and annotate rethunk usage"), OPT_BOOLEAN(0, "unret", &opts.unret, "validate entry unret placement"), OPT_BOOLEAN('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"), OPT_BOOLEAN('s', "stackval", &opts.stackval, "validate frame pointer rules"), @@ -124,6 +125,7 @@ static bool opts_valid(void) opts.noinstr || opts.orc || opts.retpoline || + opts.rethunk || opts.sls || opts.stackval || opts.static_call || @@ -136,6 +138,11 @@ static bool opts_valid(void) return true; } + if (opts.unret && !opts.rethunk) { + ERROR("--unret requires --rethunk"); + return false; + } + if (opts.dump_orc) return true; diff --git a/tools/objtool/check.c b/tools/objtool/check.c index ddfdd138cc2a3..7bebdb8867cdc 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -3732,8 +3732,11 @@ static int validate_retpoline(struct objtool_file *file) continue; if (insn->type == INSN_RETURN) { - WARN_FUNC("'naked' return found in RETPOLINE build", - insn->sec, insn->offset); + if (opts.rethunk) { + WARN_FUNC("'naked' return found in RETHUNK build", + insn->sec, insn->offset); + } else + continue; } else { WARN_FUNC("indirect %s found in RETPOLINE build", insn->sec, insn->offset, @@ -4264,7 +4267,9 @@ int check(struct objtool_file *file) if (ret < 0) goto out; warnings += ret; + } + if (opts.rethunk) { ret = create_return_sites_sections(file); if (ret < 0) goto out; diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h index 0c476b0b40a3f..42a52f1a0add5 100644 --- a/tools/objtool/include/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h @@ -19,6 +19,7 @@ struct opts { bool noinstr; bool orc; bool retpoline; + bool rethunk; bool unret; bool sls; bool stackval; |