From: David Howells <dhowells@redhat.com>
Date: Fri, 20 Oct 2017 16:01:22 +0000 (+0100)
Subject: rxrpc: Don't release call mutex on error pointer
X-Git-Tag: Ubuntu-5.13.0-19.19~12373^2~4
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=6cb3ece9685f78f9b288dd2afea58c35784e40b8;p=mirror_ubuntu-jammy-kernel.git

rxrpc: Don't release call mutex on error pointer

Don't release call mutex at the end of rxrpc_kernel_begin_call() if the
call pointer actually holds an error value.

Fixes: 540b1c48c37a ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index fb17552fd292..4b0a8288c98a 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -308,10 +308,11 @@ struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 	call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, tx_total_len,
 				     gfp);
 	/* The socket has been unlocked. */
-	if (!IS_ERR(call))
+	if (!IS_ERR(call)) {
 		call->notify_rx = notify_rx;
+		mutex_unlock(&call->user_mutex);
+	}
 
-	mutex_unlock(&call->user_mutex);
 	_leave(" = %p", call);
 	return call;
 }