ceph: fix possible NULL pointer dereference for req->r_session

The request will be inserted into the ci->i_unsafe_dirops before
assigning the req->r_session, so it's possible that we will hit
NULL pointer dereference bug here.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/55327
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Xiubo Li 2022-04-14 09:07:21 +08:00 committed by Ilya Dryomov
parent 396ea16818
commit 7acae6183c

View file

@ -2274,6 +2274,8 @@ static int unsafe_request_wait(struct inode *inode)
list_for_each_entry(req, &ci->i_unsafe_dirops,
r_unsafe_dir_item) {
s = req->r_session;
if (!s)
continue;
if (unlikely(s->s_mds >= max_sessions)) {
spin_unlock(&ci->i_unsafe_lock);
for (i = 0; i < max_sessions; i++) {
@ -2294,6 +2296,8 @@ static int unsafe_request_wait(struct inode *inode)
list_for_each_entry(req, &ci->i_unsafe_iops,
r_unsafe_target_item) {
s = req->r_session;
if (!s)
continue;
if (unlikely(s->s_mds >= max_sessions)) {
spin_unlock(&ci->i_unsafe_lock);
for (i = 0; i < max_sessions; i++) {