kernel/git/stable/linux.git/fs/ceph/caps.c, branch linux-5.4.y

ceph: fix deadlock or deadcode of misusing dget()

2024-02-23T07:25:03+00:00

[ Upstream commit b493ad718b1f0357394d2cdecbf00a44a36fa085 ] The lock order is incorrect between denty and its parent, we should always make sure that the parent get the lock first. But since this deadcode is never used and the parent dir will always be set from the callers, let's just remove it. Link: https://lore.kernel.org/r/20231116081919.GZ1957730@ZenIV Reported-by: Al Viro Signed-off-by: Xiubo Li Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin

ceph: show tasks waiting on caps in debugfs caps file

2023-08-11T09:54:00+00:00

[ Upstream commit 3a3430affce5de301fc8e6e50fa3543d7597820e ] Add some visibility of tasks that are waiting for caps to the "caps" debugfs file. Display the tgid of the waiting task, inode number, and the caps the task needs and wants. Signed-off-by: Jeff Layton Reviewed-by: "Yan, Zheng" Signed-off-by: Ilya Dryomov Stable-dep-of: e7e607bd0048 ("ceph: defer stopping mdsc delayed_work") Signed-off-by: Sasha Levin

ceph: don't let check_caps skip sending responses for revoke msgs

2023-07-27T06:37:38+00:00

commit 257e6172ab36ebbe295a6c9ee9a9dd0fe54c1dc2 upstream. If a client sends out a cap update dropping caps with the prior 'seq' just before an incoming cap revoke request, then the client may drop the revoke because it believes it's already released the requested capabilities. This causes the MDS to wait indefinitely for the client to respond to the revoke. It's therefore always a good idea to ack the cap revoke request with the bumped up 'seq'. Cc: stable@vger.kernel.org Link: https://tracker.ceph.com/issues/61782 Signed-off-by: Xiubo Li Reviewed-by: Milind Changire Reviewed-by: Patrick Donnelly Signed-off-by: Ilya Dryomov Signed-off-by: Greg Kroah-Hartman

ceph: fix use-after-free bug for inodes when flushing capsnaps

2023-06-14T08:59:57+00:00

commit 409e873ea3c1fd3079909718bbeb06ac1ec7f38b upstream. There is a race between capsnaps flush and removing the inode from 'mdsc->snap_flush_list' list: == Thread A == == Thread B == ceph_queue_cap_snap() -> allocate 'capsnapA' ->ihold('&ci->vfs_inode') ->add 'capsnapA' to 'ci->i_cap_snaps' ->add 'ci' to 'mdsc->snap_flush_list' ... == Thread C == ceph_flush_snaps() ->__ceph_flush_snaps() ->__send_flush_snap() handle_cap_flushsnap_ack() ->iput('&ci->vfs_inode') this also will release 'ci' ... == Thread D == ceph_handle_snap() ->flush_snaps() ->iterate 'mdsc->snap_flush_list' ->get the stale 'ci' ->remove 'ci' from ->ihold(&ci->vfs_inode) this 'mdsc->snap_flush_list' will WARNING To fix this we will increase the inode's i_count ref when adding 'ci' to the 'mdsc->snap_flush_list' list. [ idryomov: need_put int -> bool ] Cc: stable@vger.kernel.org Link: https://bugzilla.redhat.com/show_bug.cgi?id=2209299 Signed-off-by: Xiubo Li Reviewed-by: Milind Changire Reviewed-by: Ilya Dryomov Signed-off-by: Ilya Dryomov Signed-off-by: Greg Kroah-Hartman

ceph: fix handling of "meta" errors

2021-10-27T07:54:27+00:00

commit 1bd85aa65d0e7b5e4d09240f492f37c569fdd431 upstream. Currently, we check the wb_err too early for directories, before all of the unsafe child requests have been waited on. In order to fix that we need to check the mapping->wb_err later nearer to the end of ceph_fsync. We also have an overly-complex method for tracking errors after blocklisting. The errors recorded in cleanup_session_requests go to a completely separate field in the inode, but we end up reporting them the same way we would for any other error (in fsync). There's no real benefit to tracking these errors in two different places, since the only reporting mechanism for them is in fsync, and we'd need to advance them both every time. Given that, we can just remove i_meta_err, and convert the places that used it to instead just use mapping->wb_err instead. That also fixes the original problem by ensuring that we do a check_and_advance of the wb_err at the end of the fsync op. Cc: stable@vger.kernel.org URL: https://tracker.ceph.com/issues/52864 Reported-by: Patrick Donnelly Signed-off-by: Jeff Layton Reviewed-by: Xiubo Li Signed-off-by: Ilya Dryomov Signed-off-by: Greg Kroah-Hartman

ceph: lockdep annotations for try_nonblocking_invalidate

2021-09-26T12:07:11+00:00

[ Upstream commit 3eaf5aa1cfa8c97c72f5824e2e9263d6cc977b03 ] Signed-off-by: Jeff Layton Reviewed-by: Ilya Dryomov Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin

ceph: reduce contention in ceph_check_delayed_caps()

2021-08-18T06:56:57+00:00

commit bf2ba432213fade50dd39f2e348085b758c0726e upstream. Function ceph_check_delayed_caps() is called from the mdsc->delayed_work workqueue and it can be kept looping for quite some time if caps keep being added back to the mdsc->cap_delay_list. This may result in the watchdog tainting the kernel with the softlockup flag. This patch breaks this loop if the caps have been recently (i.e. during the loop execution). Any new caps added to the list will be handled in the next run. Also, allow schedule_delayed() callers to explicitly set the delay value instead of defaulting to 5s, so we can ensure that it runs soon afterward if it looks like there is more work. Cc: stable@vger.kernel.org URL: https://tracker.ceph.com/issues/46284 Signed-off-by: Luis Henriques Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Greg Kroah-Hartman

ceph: fix fscache invalidation

2021-05-22T09:38:29+00:00

[ Upstream commit 10a7052c7868bc7bc72d947f5aac6f768928db87 ] Ensure that we invalidate the fscache whenever we invalidate the pagecache. Signed-off-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin

ceph: fix race in concurrent __ceph_remove_cap invocations

2020-12-30T10:51:40+00:00

commit e5cafce3ad0f8652d6849314d951459c2bff7233 upstream. A NULL pointer dereference may occur in __ceph_remove_cap with some of the callbacks used in ceph_iterate_session_caps, namely trim_caps_cb and remove_session_caps_cb. Those callers hold the session->s_mutex, so they are prevented from concurrent execution, but ceph_evict_inode does not. Since the callers of this function hold the i_ceph_lock, the fix is simply a matter of returning immediately if caps->ci is NULL. Cc: stable@vger.kernel.org URL: https://tracker.ceph.com/issues/43272 Suggested-by: Jeff Layton Signed-off-by: Luis Henriques Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Greg Kroah-Hartman

ceph: fix potential race in ceph_check_caps

2020-10-01T11:18:08+00:00

[ Upstream commit dc3da0461cc4b76f2d0c5b12247fcb3b520edbbf ] Nothing ensures that session will still be valid by the time we dereference the pointer. Take and put a reference. In principle, we should always be able to get a reference here, but throw a warning if that's ever not the case. Signed-off-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin