diff options
| author | Martin Schiller <ms@dev.tdt.de> | 2020-01-09 07:31:14 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-29 10:21:53 +0100 |
| commit | 52a9551156693ae6fd7ce7962e76e22b890d4335 (patch) | |
| tree | aba5dc12cdf8e4341d38191cc06cd31c31af796a /net/x25/af_x25.c | |
| parent | 2348440cfde4422e4ccec56f5d5cdd0a699cec80 (diff) | |
net/x25: fix nonblocking connect
commit e21dba7a4df4d93da237da65a096084b4f2e87b4 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/x25/af_x25.c')
| -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 f330475a87ff..f9fb8613fb28 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -764,6 +764,10 @@ 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; @@ -810,7 +814,7 @@ 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) |