From: Peter Zijlstra peterz@infradead.org
stable inclusion from stable-v5.10.133 commit 03c5c33e043e77a1a848c52f37c512efb412f2c3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5PTAS CVE: CVE-2022-29900,CVE-2022-23816,CVE-2022-29901
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit 1ffbe4e935f9b7308615c75be990aec07464d1e7 upstream.
Ignore all INT3 instructions for unreachable code warnings, similar to NOP. This allows using INT3 for various paddings instead of NOPs.
Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Acked-by: Josh Poimboeuf jpoimboe@redhat.com Link: https://lore.kernel.org/r/20220308154317.343312938@infradead.org Signed-off-by: Thadeu Lima de Souza Cascardo cascardo@canonical.com Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Lin Yujun linyujun809@huawei.com Reviewed-by: Zhang Jianhua chris.zjh@huawei.com --- tools/objtool/check.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 9943987b24a9..fdf96eef6e00 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2775,9 +2775,8 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, switch (insn->type) {
case INSN_RETURN: - if (next_insn && next_insn->type == INSN_TRAP) { - next_insn->ignore = true; - } else if (sls && !insn->retpoline_safe) { + if (sls && !insn->retpoline_safe && + next_insn && next_insn->type != INSN_TRAP) { WARN_FUNC("missing int3 after ret", insn->sec, insn->offset); } @@ -2824,9 +2823,8 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, break;
case INSN_JUMP_DYNAMIC: - if (next_insn && next_insn->type == INSN_TRAP) { - next_insn->ignore = true; - } else if (sls && !insn->retpoline_safe) { + if (sls && !insn->retpoline_safe && + next_insn && next_insn->type != INSN_TRAP) { WARN_FUNC("missing int3 after indirect jump", insn->sec, insn->offset); } @@ -2997,7 +2995,7 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio int i; struct instruction *prev_insn;
- if (insn->ignore || insn->type == INSN_NOP) + if (insn->ignore || insn->type == INSN_NOP || insn->type == INSN_TRAP) return true;
/*