From: Harshvardhan Jha <harshvardhan.jha@xxxxxxxxxx> commit 732b33d0dbf17e9483f0b50385bf606f724f50a2 upstream. This patch addresses the following problems: - priv can never be NULL, so this part of the check is useless - if the loop ran through the whole list, priv->client is invalid and it is more appropriate and sufficient to check for the end of list_for_each_entry loop condition. Link: http://lkml.kernel.org/r/20210727000709.225032-1-harshvardhan.jha@xxxxxxxxxx Signed-off-by: Harshvardhan Jha <harshvardhan.jha@xxxxxxxxxx> Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx> Tested-by: Stefano Stabellini <sstabellini@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Dominique Martinet <asmadeus@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/9p/trans_xen.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -138,7 +138,7 @@ static bool p9_xen_write_todo(struct xen static int p9_xen_request(struct p9_client *client, struct p9_req_t *p9_req) { - struct xen_9pfs_front_priv *priv = NULL; + struct xen_9pfs_front_priv *priv; RING_IDX cons, prod, masked_cons, masked_prod; unsigned long flags; u32 size = p9_req->tc.size; @@ -151,7 +151,7 @@ static int p9_xen_request(struct p9_clie break; } read_unlock(&xen_9pfs_lock); - if (!priv || priv->client != client) + if (list_entry_is_head(priv, &xen_9pfs_devs, list)) return -EINVAL; num = p9_req->tc.tag % priv->num_rings;