diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2018-08-08 19:23:14 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2018-08-08 12:06:17 -0700 |
| commit | 7c81c71730456845e6212dccbf00098faa66740f (patch) | |
| tree | 22562f2b30e843b45f880f531ac8986253355462 | |
| parent | 5121700b346b6160ccc9411194e3f1f417c340d1 (diff) | |
| download | linux-4.18.y-7c81c71730456845e6212dccbf00098faa66740f.tar.gz | |
bpf, sockmap: fix leak in bpf_tcp_sendmsg wait for mem path
In bpf_tcp_sendmsg() the sk_alloc_sg() may fail. In the case of
ENOMEM, it may also mean that we've partially filled the scatterlist
entries with pages. Later jumping to sk_stream_wait_memory()
we could further fail with an error for several reasons, however
we miss to call free_start_sg() if the local sk_msg_buff was used.
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 | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index f7360c4d725026..c4d75c52b4fc13 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -1048,7 +1048,7 @@ static int bpf_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); while (msg_data_left(msg)) { - struct sk_msg_buff *m; + struct sk_msg_buff *m = NULL; bool enospc = false; int copy; @@ -1116,8 +1116,11 @@ wait_for_sndbuf: set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); wait_for_memory: err = sk_stream_wait_memory(sk, &timeo); - if (err) + if (err) { + if (m && m != psock->cork) + free_start_sg(sk, m); goto out_err; + } } out_err: if (err < 0) |