From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Mon, 6 Sep 2021 09:43:01 +0000 (+0300)
Subject: ceph: fix off by one bugs in unsafe_request_wait()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=708c87168b6121abc74b2a57d0c498baaf70cbea;p=linux.git

ceph: fix off by one bugs in unsafe_request_wait()

The "> max" tests should be ">= max" to prevent an out of bounds access
on the next lines.

Fixes: e1a4541ec0b9 ("ceph: flush the mdlog before waiting on unsafe reqs")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 6c0e52fd0743e..3e42d0466521f 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -2263,7 +2263,7 @@ retry:
 			list_for_each_entry(req, &ci->i_unsafe_dirops,
 					    r_unsafe_dir_item) {
 				s = req->r_session;
-				if (unlikely(s->s_mds > max)) {
+				if (unlikely(s->s_mds >= max)) {
 					spin_unlock(&ci->i_unsafe_lock);
 					goto retry;
 				}
@@ -2277,7 +2277,7 @@ retry:
 			list_for_each_entry(req, &ci->i_unsafe_iops,
 					    r_unsafe_target_item) {
 				s = req->r_session;
-				if (unlikely(s->s_mds > max)) {
+				if (unlikely(s->s_mds >= max)) {
 					spin_unlock(&ci->i_unsafe_lock);
 					goto retry;
 				}