[PATCH 4.19 273/361] nfsd: Fix an Oops in free_session()

Greg Kroah-Hartman
2018-11-11T23:54:48Z

From: Trond Myklebust <trondmy@gmail.com>

commit bb6ad5572c0022e17e846b382d7413cdcf8055be upstream.

In call_xpt_users(), we delete the entry from the list, but we
do not reinitialise it. This triggers the list poisoning when
we later call unregister_xpt_user() in nfsd4_del_conns().

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
net/sunrpc/svc_xprt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -989,7 +989,7 @@ static void call_xpt_users(struct svc_xp
spin_lock(&xprt->xpt_lock);
while (!list_empty(&xprt->xpt_users)) {
u = list_first_entry(&xprt->xpt_users, struct svc_xpt_user, list);
- list_del(&u->list);
+ list_del_init(&u->list);
u->callback(u);
}
spin_unlock(&xprt->xpt_lock);