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 16:43:24 +0100 |
| commit | 868f9e509e8f774681e387a0f39f850c06560c7e (patch) | |
| tree | d5650af8132e0b726087cfe51dbc1773a7e0a17f | |
| parent | 1f7a1bcd27c388b4cc286e943218c69db2d3ba71 (diff) | |
| download | linux-stable-868f9e509e8f774681e387a0f39f850c06560c7e.tar.gz linux-stable-868f9e509e8f774681e387a0f39f850c06560c7e.tar.bz2 linux-stable-868f9e509e8f774681e387a0f39f850c06560c7e.zip | |
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>
| -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 20a511398389..bd1cbbfe5924 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -765,6 +765,10 @@ 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; @@ -811,7 +815,7 @@ 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) |