On Mon, 2022-04-18 at 09:44 +0800, Xiubo Li wrote: > 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. > > URL: https://tracker.ceph.com/issues/55327 > Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx> > --- > fs/ceph/caps.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c > index 69af17df59be..c70fd747c914 100644 > --- a/fs/ceph/caps.c > +++ b/fs/ceph/caps.c > @@ -2333,6 +2333,8 @@ 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++) { > @@ -2353,6 +2355,8 @@ 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++) { Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
