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| author | Martin Schiller <ms@dev.tdt.de> | 2020-01-09 07:31:14 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-29 16:45:33 +0100 |
| commit | d8a11e0f4e26f033a217a24617c11bcd24b8f65a (patch) | |
| tree | bd17b521fb19453c36fa015317bb8f9d2899a3c9 /net/x25 | |
| parent | ce75dd3abbc8f1be531ac5de559d59df9098020c (diff) | |
| download | linux-stable-d8a11e0f4e26f033a217a24617c11bcd24b8f65a.tar.gz linux-stable-d8a11e0f4e26f033a217a24617c11bcd24b8f65a.tar.bz2 linux-stable-d8a11e0f4e26f033a217a24617c11bcd24b8f65a.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>
Diffstat (limited to 'net/x25')
| -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 6aee9f5e8e71..256f3e97d1f3 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -760,6 +760,10 @@ 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; @@ -806,7 +810,7 @@ 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) |