Message ID | 20230721092725.3795-2-laoar.shao@gmail.com (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | BPF |
Headers | show |
Series | bpf: Fix fill_link_info and add selftest | expand |
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 7f4e8c3..ad9360d 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3376,16 +3376,16 @@ static int bpf_perf_link_fill_common(const struct perf_event *event, size_t len; int err; - 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 (!ulen ^ !uname) + return -EINVAL; + if (!uname) + return 0; + if (buf) { len = strlen(buf); err = bpf_copy_to_user(uname, buf, ulen, len);
The patch 1b715e1b0ec5: "bpf: Support ->fill_link_info for perf_event" from Jul 9, 2023, 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. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/bpf/85697a7e-f897-4f74-8b43-82721bebc462@kili.mountain/ Signed-off-by: Yafang Shao <laoar.shao@gmail.com> --- kernel/bpf/syscall.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)