unix/caif: sk_socket can disappear when state is unlocked
got a rare NULL pointer dereference in clear_bit
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
----
v2: switch to sock_flag(sk, SOCK_DEAD) and added net/caif/caif_socket.c
v3: return -ECONNRESET in upstream caller of wait function for SOCK_DEAD
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
index 4ec0c80..112ad78 100644
--- a/net/caif/caif_socket.c
+++ b/net/caif/caif_socket.c
@@ -330,6 +330,10 @@
release_sock(sk);
timeo = schedule_timeout(timeo);
lock_sock(sk);
+
+ if (sock_flag(sk, SOCK_DEAD))
+ break;
+
clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
}
@@ -373,6 +377,10 @@
struct sk_buff *skb;
lock_sock(sk);
+ if (sock_flag(sk, SOCK_DEAD)) {
+ err = -ECONNRESET;
+ goto unlock;
+ }
skb = skb_dequeue(&sk->sk_receive_queue);
caif_check_flow_release(sk);