diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2018-08-08 19:23:13 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2018-08-08 12:06:17 -0700 |
| commit | 5121700b346b6160ccc9411194e3f1f417c340d1 (patch) | |
| tree | 519bc8a547f5550b747006fefc61f0c120196164 | |
| parent | 74682128c6e456b529b25b95ba807484ce58a753 (diff) | |
| download | linux-4.18.y-5121700b346b6160ccc9411194e3f1f417c340d1.tar.gz | |
bpf, sockmap: fix bpf_tcp_sendmsg sock error handling
While working on bpf_tcp_sendmsg() code, I noticed that when a
sk->sk_err is set we error out with err = sk->sk_err. However
this is problematic since sk->sk_err is a positive error value
and therefore we will neither go into sk_stream_error() nor will
we report an error back to user space. I had this case with EPIPE
and user space was thinking sendmsg() succeeded since EPIPE is
a positive value, thinking we submitted 32 bytes. Fix it by
negating the sk->sk_err value.
Fixes: 4f738adba30a ("bpf: create tcp_bpf_ulp allowing BPF to monitor socket TX/RX data")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | kernel/bpf/sockmap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index 98fb7938beea9d..f7360c4d725026 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -1053,7 +1053,7 @@ static int bpf_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) int copy; if (sk->sk_err) { - err = sk->sk_err; + err = -sk->sk_err; goto out_err; } |