nbd: prevent memory leak

commit 03bf73c315edca28f47451913177e14cd040a216 upstream.

In nbd_add_socket when krealloc succeeds, if nsock's allocation fail the
reallocted memory is leak. The correct behaviour should be assigning the
reallocted memory to config->socks right after success.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 19e7599..5753246 100644 (file)
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1032,14 +1032,15 @@ static int nbd_add_socket(struct nbd_device *nbd, unsigned long arg,
                sockfd_put(sock);
                return -ENOMEM;
        }
+
+       config->socks = socks;
+
        nsock = kzalloc(sizeof(struct nbd_sock), GFP_KERNEL);
        if (!nsock) {
                sockfd_put(sock);
                return -ENOMEM;
        }
 
-       config->socks = socks;
-
        nsock->fallback_index = -1;
        nsock->dead = false;
        mutex_init(&nsock->tx_lock);