From 0aa35162d2a1ed7ae5303b8d91f7290d3b8b9219 Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Sun, 13 Aug 2023 14:18:59 +0000 Subject: [PATCH] bpf: Fix uninitialized symbol in bpf_perf_link_fill_kprobe() The commit 1b715e1b0ec5 ("bpf: Support ->fill_link_info for perf_event") leads to the following Smatch static checker warning: kernel/bpf/syscall.c:3416 bpf_perf_link_fill_kprobe() error: uninitialized symbol 'type'. That can happens when uname is NULL. So fix it by verifying the uname when we really need to fill it. Fixes: 1b715e1b0ec5 ("bpf: Support ->fill_link_info for perf_event") Reported-by: Dan Carpenter Signed-off-by: Yafang Shao Signed-off-by: Daniel Borkmann Acked-by: Yonghong Song Acked-by: Jiri Olsa Closes: https://lore.kernel.org/bpf/85697a7e-f897-4f74-8b43-82721bebc462@kili.mountain Link: https://lore.kernel.org/bpf/20230813141900.1268-2-laoar.shao@gmail.com --- kernel/bpf/syscall.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 7f4e8c357a6af..cb658543bdb46 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3378,14 +3378,13 @@ static int bpf_perf_link_fill_common(const struct perf_event *event, if (!ulen ^ !uname) return -EINVAL; - if (!uname) - return 0; err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, probe_offset, probe_addr); if (err) return err; - + if (!uname) + return 0; if (buf) { len = strlen(buf); err = bpf_copy_to_user(uname, buf, ulen, len); -- 2.30.2