kernel/git/stable/linux.git/fs/gfs2, branch linux-5.11.y

gfs2: report "already frozen/thawed" errors

2021-04-16T09:38:13+00:00

[ Upstream commit ff132c5f93c06bd4432bbab5c369e468653bdec4 ] Before this patch, gfs2's freeze function failed to report an error when the target file system was already frozen as it should (and as generic vfs function freeze_super does. Similarly, gfs2's thaw function failed to report an error when trying to thaw a file system that is not frozen, as vfs function thaw_super does. The errors were checked, but it always returned a 0 return code. This patch adds the missing error return codes to gfs2 freeze and thaw. Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher Signed-off-by: Sasha Levin

gfs2: Flag a withdraw if init_threads() fails

2021-04-16T09:38:12+00:00

[ Upstream commit 62dd0f98a0e5668424270b47a0c2e973795faba7 ] Interrupting mount with ^C quickly enough can cause the kthread_run() calls in gfs2's init_threads() to fail and the error path leads to a deadlock on the s_umount rwsem. The abridged chain of events is: [mount path] get_tree_bdev() sget_fc() alloc_super() down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING); [acquired] gfs2_fill_super() gfs2_make_fs_rw() init_threads() kthread_run() ( Interrupted ) [Error path] gfs2_gl_hash_clear() flush_workqueue(glock_workqueue) wait_for_completion() [workqueue context] glock_work_func() run_queue() do_xmote() freeze_go_sync() freeze_super() down_write(&sb->s_umount) [deadlock] In freeze_go_sync() there is a gfs2_withdrawn() check that we can use to make sure freeze_super() is not called in the error path, so add a gfs2_withdraw_delayed() call when init_threads() fails. Ref: https://bugzilla.kernel.org/show_bug.cgi?id=212231 Reported-by: Alexander Aring Signed-off-by: Andrew Price Signed-off-by: Andreas Gruenbacher Signed-off-by: Sasha Levin

gfs2: fix use-after-free in trans_drain

2021-03-30T12:30:08+00:00

[ Upstream commit 1a5a2cfd34c17db73c53ef127272c8c1ae220485 ] This patch adds code to function trans_drain to remove drained bd elements from the ail lists, if queued, before freeing the bd. If we don't remove the bd from the ail, function ail_drain will try to reference the bd after it has been freed by trans_drain. Thanks to Andy Price for his analysis of the problem. Reported-by: Andy Price Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher Signed-off-by: Sasha Levin

gfs2: bypass signal_our_withdraw if no journal

2021-03-20T09:51:13+00:00

[ Upstream commit d5bf630f355d8c532bef2347cf90e8ae60a5f1bd ] Before this patch, function signal_our_withdraw referenced the journal inode immediately. But corrupt file systems may have some invalid journals, in which case our attempt to read it in will withdraw and the resulting signal_our_withdraw would dereference the NULL value. This patch adds a check to signal_our_withdraw so that if the journal has not yet been initialized, it simply returns and does the old-style withdraw. Thanks, Andy Price, for his analysis. Reported-by: syzbot+50a8a9cf8127f2c6f5df@syzkaller.appspotmail.com Fixes: 601ef0d52e96 ("gfs2: Force withdraw to replay journals and wait for it to finish") Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher Signed-off-by: Sasha Levin

gfs2: move freeze glock outside the make_fs_rw and _ro functions

2021-03-20T09:51:13+00:00

[ Upstream commit 96b1454f2e8ede4c619fde405a1bb4e9ba8d218e ] Before this patch, sister functions gfs2_make_fs_rw and gfs2_make_fs_ro locked (held) the freeze glock by calling gfs2_freeze_lock and gfs2_freeze_unlock. The problem is, not all the callers of gfs2_make_fs_ro should be doing this. The three callers of gfs2_make_fs_ro are: remount (gfs2_reconfigure), signal_our_withdraw, and unmount (gfs2_put_super). But when unmounting the file system we can get into the following circular lock dependency: deactivate_super down_write(&s->s_umount); <-------------------------------------- s_umount deactivate_locked_super gfs2_kill_sb kill_block_super generic_shutdown_super gfs2_put_super gfs2_make_fs_ro gfs2_glock_nq_init sd_freeze_gl freeze_go_sync if (freeze glock in SH) freeze_super (vfs) down_write(&sb->s_umount); <------- s_umount This patch moves the hold of the freeze glock outside the two sister rw/ro functions to their callers, but it doesn't request the glock from gfs2_put_super, thus eliminating the circular dependency. Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher Signed-off-by: Sasha Levin

gfs2: Add common helper for holding and releasing the freeze glock

2021-03-20T09:51:13+00:00

[ Upstream commit c77b52c0a137994ad796f44544c802b0b766e496 ] Many places in the gfs2 code queued and dequeued the freeze glock. Almost all of them acquire it in SHARED mode, and need to specify the same LM_FLAG_NOEXP and GL_EXACT flags. This patch adds common helper functions gfs2_freeze_lock and gfs2_freeze_unlock to make the code more readable, and to prepare for the next patch. Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher Signed-off-by: Sasha Levin

gfs2: Recursive gfs2_quota_hold in gfs2_iomap_end

2021-03-04T11:15:41+00:00

commit 7009fa9cd9a5262944b30eb7efb1f0561d074b68 upstream. When starting an iomap write, gfs2_quota_lock_check -> gfs2_quota_lock -> gfs2_quota_hold is called from gfs2_iomap_begin. At the end of the write, before unlocking the quotas, punch_hole -> gfs2_quota_hold can be called again in gfs2_iomap_end, which is incorrect and leads to a failed assertion. Instead, move the call to gfs2_quota_unlock before the call to punch_hole to fix that. Fixes: 64bc06bb32ee ("gfs2: iomap buffered write support") Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Andreas Gruenbacher Signed-off-by: Greg Kroah-Hartman

gfs2: Lock imbalance on error path in gfs2_recover_one

2021-03-04T11:15:41+00:00

commit 834ec3e1ee65029029225a86c12337a6cd385af7 upstream. In gfs2_recover_one, fix a sd_log_flush_lock imbalance when a recovery pass fails. Fixes: c9ebc4b73799 ("gfs2: allow journal replay to hold sd_log_flush_lock") Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Andreas Gruenbacher Signed-off-by: Greg Kroah-Hartman

gfs2: Don't skip dlm unlock if glock has an lvb

2021-03-04T11:15:41+00:00

commit 78178ca844f0eb88f21f31c7fde969384be4c901 upstream. Patch fb6791d100d1 was designed to allow gfs2 to unmount quicker by skipping the step where it tells dlm to unlock glocks in EX with lvbs. This was done because when gfs2 unmounts a file system, it destroys the dlm lockspace shortly after it destroys the glocks so it doesn't need to unlock them all: the unlock is implied when the lockspace is destroyed by dlm. However, that patch introduced a use-after-free in dlm: as part of its normal dlm_recoverd process, it can call ls_recovery to recover dead locks. In so doing, it can call recover_rsbs which calls recover_lvb for any mastered rsbs. Func recover_lvb runs through the list of lkbs queued to the given rsb (if the glock is cached but unlocked, it will still be queued to the lkb, but in NL--Unlocked--mode) and if it has an lvb, copies it to the rsb, thus trying to preserve the lkb. However, when gfs2 skips the dlm unlock step, it frees the glock and its lvb, which means dlm's function recover_lvb references the now freed lvb pointer, copying the freed lvb memory to the rsb. This patch changes the check in gdlm_put_lock so that it calls dlm_unlock for all glocks that contain an lvb pointer. Fixes: fb6791d100d1 ("GFS2: skip dlm_unlock calls in unmount") Cc: stable@vger.kernel.org # v3.8+ Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher Signed-off-by: Greg Kroah-Hartman

gfs2: fix glock confusion in function signal_our_withdraw

2021-03-04T11:15:41+00:00

commit f5f02fde9f52b2d769c1c2ddfd3d9c4a1fe739a7 upstream. If go_free is defined, function signal_our_withdraw is supposed to synchronize on the GLF_FREEING flag of the inode glock, but it accidentally does that on the live glock. Fix that and disambiguate the glock variables. Fixes: 601ef0d52e96 ("gfs2: Force withdraw to replay journals and wait for it to finish") Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Bob Peterson Signed-off-by: Greg Kroah-Hartman