From: Masami Hiramatsu (Google) Date: Sat, 17 Feb 2024 12:25:42 +0000 (+0900) Subject: tracing/probes: Fix to search structure fields correctly X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=9704669c386f9bbfef2e002e7e690c56b7dcf5de;p=linux.git tracing/probes: Fix to search structure fields correctly 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. Link: https://lore.kernel.org/all/170791694361.389532.10047514554799419688.stgit@devnote2/ Fixes: 302db0f5b3d8 ("tracing/probes: Add a function to search a member of a struct/union") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) --- diff --git a/kernel/trace/trace_btf.c b/kernel/trace/trace_btf.c index ca224d53bfdcd..5bbdbcbbde3cd 100644 --- a/kernel/trace/trace_btf.c +++ b/kernel/trace/trace_btf.c @@ -91,8 +91,8 @@ retry: 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;