linux-kernel - [PATCH RFC 1/5] tracing/probes: Fix to search structure fields correctly

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <170791694361.389532.10047514554799419688.stgit@devnote2>
Date: Wed, 14 Feb 2024 22:22:23 +0900
From: "Masami Hiramatsu (Google)" <mhiramat@...nel.org>
To: linux-trace-kernel@...r.kernel.org
Cc: linux-kernel@...r.kernel.org,
	Steven Rostedt <rostedt@...dmis.org>,
	mhiramat@...nel.org
Subject: [PATCH RFC 1/5] tracing/probes: Fix to search structure fields correctly

From: Masami Hiramatsu (Google) <mhiramat@...nel.org>

Fix to search a field from the structure which has anonymous union
correctly.
Since the reference `type` pointer was updated in the loop, the search
loop suddenly aborted where it hits an anonymous union. Thus it can not
find the field after the anonymous union. This avoids updating the
cursor `type` pointer in the loop.

Fixes: 302db0f5b3d8 ("tracing/probes: Add a function to search a member of a struct/union")
Cc: stable@...r.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@...nel.org>
---
 kernel/trace/trace_btf.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_btf.c b/kernel/trace/trace_btf.c
index ca224d53bfdc..5bbdbcbbde3c 100644
--- a/kernel/trace/trace_btf.c
+++ b/kernel/trace/trace_btf.c
@@ -91,8 +91,8 @@ const struct btf_member *btf_find_struct_member(struct btf *btf,
 	for_each_member(i, type, member) {
 		if (!member->name_off) {
 			/* Anonymous union/struct: push it for later use */
-			type = btf_type_skip_modifiers(btf, member->type, &tid);
-			if (type && top < BTF_ANON_STACK_MAX) {
+			if (btf_type_skip_modifiers(btf, member->type, &tid) &&
+			    top < BTF_ANON_STACK_MAX) {
 				anon_stack[top].tid = tid;
 				anon_stack[top++].offset =
 					cur_offset + member->offset;