nfsd: Fix an Oops in free_session()

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>

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index d16a8b423c20b613fa2bf8b8fbbd87b5ecb95033..ea7b5a3a53f071da9612b532c7a0a2dd0908d317 100644 (file)
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -1040,7 +1040,7 @@ static void call_xpt_users(struct svc_xprt *xprt)
        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);