diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2018-08-16 22:49:07 +0300 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2018-08-17 00:58:08 +0300 |
| commit | 90545cdc3f2b2ea700e24335610cd181e73756da (patch) | |
| tree | cf5bf1385744bb864f8f7844c2b98c88b9e695f4 | |
| parent | 037b0b86ecf5646f8eae777d8b52ff8b401692ec (diff) | |
| download | linux-90545cdc3f2b2ea700e24335610cd181e73756da.tar.xz | |
tcp, ulp: fix leftover icsk_ulp_ops preventing sock from reattach
I found that in BPF sockmap programs once we either delete a socket
from the map or we updated a map slot and the old socket was purged
from the map that these socket can never get reattached into a map
even though their related psock has been dropped entirely at that
point.
Reason is that tcp_cleanup_ulp() leaves the old icsk->icsk_ulp_ops
intact, so that on the next tcp_set_ulp_id() the kernel returns an
-EEXIST thinking there is still some active ULP attached.
BPF sockmap is the only one that has this issue as the other user,
kTLS, only calls tcp_cleanup_ulp() from tcp_v4_destroy_sock() whereas
sockmap semantics allow dropping the socket from the map with all
related psock state being cleaned up.
Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | net/ipv4/tcp_ulp.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/ipv4/tcp_ulp.c b/net/ipv4/tcp_ulp.c index 7dd44b6156c7..a5995bb2eaca 100644 --- a/net/ipv4/tcp_ulp.c +++ b/net/ipv4/tcp_ulp.c @@ -129,6 +129,8 @@ void tcp_cleanup_ulp(struct sock *sk) if (icsk->icsk_ulp_ops->release) icsk->icsk_ulp_ops->release(sk); module_put(icsk->icsk_ulp_ops->owner); + + icsk->icsk_ulp_ops = NULL; } /* Change upper layer protocol for socket */ |