4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jason Wang <jasowang@xxxxxxxxxx>
[ Upstream commit b8f1f65882f07913157c44673af7ec0b308d03eb ]
Sock will be NULL if we pass -1 to vhost_net_set_backend(), but when
we meet errors during ubuf allocation, the code does not check for
NULL before calling sockfd_put(), this will lead NULL
dereferencing. Fixing by checking sock pointer before.
Fixes: bab632d69ee4 ("vhost: vhost TX zero-copy support")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vhost/net.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -955,7 +955,8 @@ err_used:
if (ubufs)
vhost_net_ubuf_put_wait_and_free(ubufs);
err_ubufs:
- sockfd_put(sock);
+ if (sock)
+ sockfd_put(sock);
err_vq:
mutex_unlock(&vq->mutex);
err:
