diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2018-08-24 22:08:51 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2018-08-28 05:22:05 +0200 |
| commit | 15c480efab01197c965ce0562a43ffedd852b8f9 (patch) | |
| tree | 2f1a088152b28f8eb27233cf2aa2bc6a209f4974 /kernel | |
| parent | bpf, sockmap: fix potential use after free in bpf_tcp_close (diff) | |
| download | linux-15c480efab01197c965ce0562a43ffedd852b8f9.tar.xz linux-15c480efab01197c965ce0562a43ffedd852b8f9.zip | |
bpf, sockmap: fix psock refcount leak in bpf_tcp_recvmsg
In bpf_tcp_recvmsg() we first took a reference on the psock, however
once we find that there are skbs in the normal socket's receive queue
we return with processing them through tcp_recvmsg(). Problem is that
we leak the taken reference on the psock in that path. Given we don't
really do anything with the psock at this point, move the skb_queue_empty()
test before we fetch the psock to fix this case.
Fixes: 8934ce2fd081 ("bpf: sockmap redirect ingress support")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/sockmap.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index 01879e4d599a..26d8a3053407 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -912,6 +912,8 @@ static int bpf_tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, if (unlikely(flags & MSG_ERRQUEUE)) return inet_recv_error(sk, msg, len, addr_len); + if (!skb_queue_empty(&sk->sk_receive_queue)) + return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); rcu_read_lock(); psock = smap_psock_sk(sk); @@ -922,9 +924,6 @@ static int bpf_tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, goto out; rcu_read_unlock(); - if (!skb_queue_empty(&sk->sk_receive_queue)) - return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); - lock_sock(sk); bytes_ready: while (copied != len) { |