diff options
| author | Martin Schiller <ms@dev.tdt.de> | 2020-01-09 09:31:14 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-01-10 05:39:33 +0300 |
| commit | e21dba7a4df4d93da237da65a096084b4f2e87b4 (patch) | |
| tree | fe4194f409a60212ac0b10cc6a18b19dc14e730f | |
| parent | 3249b1e442a1be1a6b9f1026785b519d1443f807 (diff) | |
| download | linux-e21dba7a4df4d93da237da65a096084b4f2e87b4.tar.xz | |
net/x25: fix nonblocking connect
This patch fixes 2 issues in x25_connect():
1. It makes absolutely no sense to reset the neighbour and the
connection state after a (successful) nonblocking call of x25_connect.
This prevents any connection from being established, since the response
(call accept) cannot be processed.
2. Any further calls to x25_connect() while a call is pending should
simply return, instead of creating new Call Request (on different
logical channels).
This patch should also fix the "KASAN: null-ptr-deref Write in
x25_connect" and "BUG: unable to handle kernel NULL pointer dereference
in x25_connect" bugs reported by syzbot.
Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Reported-by: syzbot+429c200ffc8772bfe070@syzkaller.appspotmail.com
Reported-by: syzbot+eec0c87f31a7c3b66f7b@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/x25/af_x25.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c index 2efe44a34644..d5b09bbff375 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -766,6 +766,10 @@ static int x25_connect(struct socket *sock, struct sockaddr *uaddr, if (sk->sk_state == TCP_ESTABLISHED) goto out; + rc = -EALREADY; /* Do nothing if call is already in progress */ + if (sk->sk_state == TCP_SYN_SENT) + goto out; + sk->sk_state = TCP_CLOSE; sock->state = SS_UNCONNECTED; @@ -812,7 +816,7 @@ static int x25_connect(struct socket *sock, struct sockaddr *uaddr, /* Now the loop */ rc = -EINPROGRESS; if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) - goto out_put_neigh; + goto out; rc = x25_wait_for_connection_establishment(sk); if (rc) |