From: Fedor Pchelkin <pchelkin@xxxxxxxxx>
commit 5f397409f8ee5bc82901eeaf799e1cbc4f8edcf1 upstream.
A NULL sock pointer is passed into l2cap_sock_alloc() when it is called
from l2cap_sock_new_connection_cb() and the error handling paths should
also be aware of it.
Seemingly a more elegant solution would be to swap bt_sock_alloc() and
l2cap_chan_create() calls since they are not interdependent to that moment
but then l2cap_chan_create() adds the soon to be deallocated and still
dummy-initialized channel to the global list accessible by many L2CAP
paths. The channel would be removed from the list in short period of time
but be a bit more straight-forward here and just check for NULL instead of
changing the order of function calls.
Found by Linux Verification Center (linuxtesting.org) with SVACE static
analysis tool.
Fixes: 7c4f78cdb8e7 ("Bluetooth: L2CAP: do not leave dangling sk pointer on error in l2cap_sock_create()")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/bluetooth/l2cap_sock.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -1864,7 +1864,8 @@ static struct sock *l2cap_sock_alloc(str
chan = l2cap_chan_create();
if (!chan) {
sk_free(sk);
- sock->sk = NULL;
+ if (sock)
+ sock->sk = NULL;
return NULL;
}
Patches currently in stable-queue which might be from pchelkin@xxxxxxxxx are
queue-5.10/bluetooth-l2cap-handle-null-sock-pointer-in-l2cap_sock_alloc.patch
queue-5.10/bluetooth-l2cap-accept-zero-as-a-special-value-for-mtu-auto-selection.patch
