linux-kernel - [PATCH 4.4 158/158] ceph: hold i_ceph_lock when removing caps for freeing inode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190802092233.875646888@linuxfoundation.org>
Date:   Fri,  2 Aug 2019 11:29:39 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, "Yan, Zheng" <zyan@...hat.com>,
        Jeff Layton <jlayton@...hat.com>,
        Ilya Dryomov <idryomov@...il.com>
Subject: [PATCH 4.4 158/158] ceph: hold i_ceph_lock when removing caps for freeing inode

From: Yan, Zheng <zyan@...hat.com>

commit d6e47819721ae2d9d090058ad5570a66f3c42e39 upstream.

ceph_d_revalidate(, LOOKUP_RCU) may call __ceph_caps_issued_mask()
on a freeing inode.

Signed-off-by: "Yan, Zheng" <zyan@...hat.com>
Reviewed-by: Jeff Layton <jlayton@...hat.com>
Signed-off-by: Ilya Dryomov <idryomov@...il.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 fs/ceph/caps.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1072,20 +1072,23 @@ static int send_cap_msg(struct ceph_mds_
 }
 
 /*
- * Queue cap releases when an inode is dropped from our cache.  Since
- * inode is about to be destroyed, there is no need for i_ceph_lock.
+ * Queue cap releases when an inode is dropped from our cache.
  */
 void ceph_queue_caps_release(struct inode *inode)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct rb_node *p;
 
+	/* lock i_ceph_lock, because ceph_d_revalidate(..., LOOKUP_RCU)
+	 * may call __ceph_caps_issued_mask() on a freeing inode. */
+	spin_lock(&ci->i_ceph_lock);
 	p = rb_first(&ci->i_caps);
 	while (p) {
 		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
 		p = rb_next(p);
 		__ceph_remove_cap(cap, true);
 	}
+	spin_unlock(&ci->i_ceph_lock);
 }
 
 /*