diff options
| author | Eric Dumazet <edumazet@google.com> | 2020-03-18 19:21:02 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-03-23 13:02:01 -0700 |
| commit | 6cd6cbf593bfa3ae6fc3ed34ac21da4d35045425 (patch) | |
| tree | a92fb9e1ad95e07b71c94a62cc42a322dc7fb167 | |
| parent | 83a9b6f639e9f6b632337f9776de17d51d969c77 (diff) | |
| download | linux-6cd6cbf593bfa3ae6fc3ed34ac21da4d35045425.tar.gz | |
tcp: repair: fix TCP_QUEUE_SEQ implementation
When application uses TCP_QUEUE_SEQ socket option to
change tp->rcv_next, we must also update tp->copied_seq.
Otherwise, stuff relying on tcp_inq() being precise can
eventually be confused.
For example, tcp_zerocopy_receive() might crash because
it does not expect tcp_recv_skb() to return NULL.
We could add tests in various places to fix the issue,
or simply make sure tcp_inq() wont return a random value,
and leave fast path as it is.
Note that this fixes ioctl(fd, SIOCINQ, &val) at the same
time.
Fixes: ee9952831cfd ("tcp: Initial repair mode")
Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index eb2d80519f8e5a..dc77c303e6f7f6 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2948,8 +2948,10 @@ static int do_tcp_setsockopt(struct sock *sk, int level, err = -EPERM; else if (tp->repair_queue == TCP_SEND_QUEUE) WRITE_ONCE(tp->write_seq, val); - else if (tp->repair_queue == TCP_RECV_QUEUE) + else if (tp->repair_queue == TCP_RECV_QUEUE) { WRITE_ONCE(tp->rcv_nxt, val); + WRITE_ONCE(tp->copied_seq, val); + } else err = -EINVAL; break; |