[PATCH 4.14 155/496] xen/pvcalls: fix null pointer dereference on map->sock

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

[ Upstream commit 68d2059be660944152ba667e43c3b4ec225974bc ]

Currently if map is null then a potential null pointer deference
occurs when calling sock_release on map->sock.  I believe the
actual intention was to call sock_release on sock instead. Fix
this.

Fixes: 5db4d286a8ef ("xen/pvcalls: implement connect command")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/xen/pvcalls-back.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/xen/pvcalls-back.c
+++ b/drivers/xen/pvcalls-back.c
@@ -424,7 +424,7 @@ static int pvcalls_back_connect(struct x
 					sock);
 	if (!map) {
 		ret = -EFAULT;
-		sock_release(map->sock);
+		sock_release(sock);
 	}
 
 out: