From: Yan, Zheng <zyan@xxxxxxxxxx> commit d6e47819721ae2d9d090058ad5570a66f3c42e39 upstream. ceph_d_revalidate(, LOOKUP_RCU) may call __ceph_caps_issued_mask() on a freeing inode. Signed-off-by: "Yan, Zheng" <zyan@xxxxxxxxxx> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ceph/caps.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -1237,20 +1237,23 @@ static int send_cap_msg(struct cap_msg_a } /* - * 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); } /*