kernel/linux.git/drivers/md, branch v4.14.217

dm: eliminate potential source of excessive kernel log noise

2021-01-23T14:48:44+00:00

commit 0378c625afe80eb3f212adae42cc33c9f6f31abf upstream. There wasn't ever a real need to log an error in the kernel log for ioctls issued with insufficient permissions. Simply return an error and if an admin/user is sufficiently motivated they can enable DM's dynamic debugging to see an explanation for why the ioctls were disallowed. Reported-by: Nir Soffer Fixes: e980f62353c6 ("dm: don't allow ioctls to targets that don't map to whole devices") Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm snapshot: flush merged data before committing metadata

2021-01-23T14:48:41+00:00

commit fcc42338375a1e67b8568dbb558f8b784d0f3b01 upstream. If the origin device has a volatile write-back cache and the following events occur: 1: After finishing merge operation of one set of exceptions, merge_callback() is invoked. 2: Update the metadata in COW device tracking the merge completion. This update to COW device is flushed cleanly. 3: System crashes and the origin device's cache where the recent merge was completed has not been flushed. During the next cycle when we read the metadata from the COW device, we will skip reading those metadata whose merge was completed in step (1). This will lead to data loss/corruption. To address this, flush the origin device post merge IO before updating the metadata. Cc: stable@vger.kernel.org Signed-off-by: Akilesh Kailash Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm verity: skip verity work if I/O error when system is shutting down

2021-01-09T12:37:39+00:00

[ Upstream commit 252bd1256396cebc6fc3526127fdb0b317601318 ] If emergency system shutdown is called, like by thermal shutdown, a dm device could be alive when the block device couldn't process I/O requests anymore. In this state, the handling of I/O errors by new dm I/O requests or by those already in-flight can lead to a verity corruption state, which is a misjudgment. So, skip verity work in response to I/O error when system is shutting down. Signed-off-by: Hyeongseok Kim Reviewed-by: Sami Tolvanen Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

md/raid10: initialize r10_bio->read_slot before use.

2021-01-09T12:37:36+00:00

commit 93decc563637c4288380912eac0eb42fb246cc04 upstream. In __make_request() a new r10bio is allocated and passed to raid10_read_request(). The read_slot member of the bio is not initialized, and the raid10_read_request() uses it to index an array. This leads to occasional panics. Fix by initializing the field to invalid value and checking for valid value in raid10_read_request(). Cc: stable@vger.kernel.org Signed-off-by: Kevin Vigor Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman

md/cluster: fix deadlock when node is doing resync job

2020-12-29T12:47:10+00:00

commit bca5b0658020be90b6b504ca514fd80110204f71 upstream. md-cluster uses MD_CLUSTER_SEND_LOCK to make node can exclusively send msg. During sending msg, node can concurrently receive msg from another node. When node does resync job, grab token_lockres:EX may trigger a deadlock: ``` nodeA nodeB -------------------- -------------------- a. send METADATA_UPDATED held token_lockres:EX b. md_do_sync resync_info_update send RESYNCING + set MD_CLUSTER_SEND_LOCK + wait for holding token_lockres:EX c. mdadm /dev/md0 --remove /dev/sdg + held reconfig_mutex + send REMOVE + wait_event(MD_CLUSTER_SEND_LOCK) d. recv_daemon //METADATA_UPDATED from A process_metadata_update + (mddev_trylock(mddev) || MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD) //this time, both return false forever ``` Explaination: a. A send METADATA_UPDATED This will block another node to send msg b. B does sync jobs, which will send RESYNCING at intervals. This will be block for holding token_lockres:EX lock. c. B do "mdadm --remove", which will send REMOVE. This will be blocked by step : MD_CLUSTER_SEND_LOCK is 1. d. B recv METADATA_UPDATED msg, which send from A in step . This will be blocked by step : holding mddev lock, it makes wait_event can't hold mddev lock. (btw, MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD keep ZERO in this scenario.) There is a similar deadlock in commit 0ba959774e93 ("md-cluster: use sync way to handle METADATA_UPDATED msg") In that commit, step c is "update sb". This patch step c is "mdadm --remove". For fixing this issue, we can refer the solution of function: metadata_update_start. Which does the same grab lock_token action. lock_comm can use the same steps to avoid deadlock. By moving MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD from lock_token to lock_comm. It enlarge a little bit window of MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, but it is safe & can break deadlock. Repro steps (I only triggered 3 times with hundreds tests): two nodes share 3 iSCSI luns: sdg/sdh/sdi. Each lun size is 1GB. ``` ssh root@node2 "mdadm -S --scan" mdadm -S --scan for i in {g,h,i};do dd if=/dev/zero of=/dev/sd$i oflag=direct bs=1M \ count=20; done mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sdg /dev/sdh \ --bitmap-chunk=1M ssh root@node2 "mdadm -A /dev/md0 /dev/sdg /dev/sdh" sleep 5 mkfs.xfs /dev/md0 mdadm --manage --add /dev/md0 /dev/sdi mdadm --wait /dev/md0 mdadm --grow --raid-devices=3 /dev/md0 mdadm /dev/md0 --fail /dev/sdg mdadm /dev/md0 --remove /dev/sdg mdadm --grow --raid-devices=2 /dev/md0 ``` test script will hung when executing "mdadm --remove". ``` # dump stacks by "echo t > /proc/sysrq-trigger" md0_cluster_rec D 0 5329 2 0x80004000 Call Trace: __schedule+0x1f6/0x560 ? _cond_resched+0x2d/0x40 ? schedule+0x4a/0xb0 ? process_metadata_update.isra.0+0xdb/0x140 [md_cluster] ? wait_woken+0x80/0x80 ? process_recvd_msg+0x113/0x1d0 [md_cluster] ? recv_daemon+0x9e/0x120 [md_cluster] ? md_thread+0x94/0x160 [md_mod] ? wait_woken+0x80/0x80 ? md_congested+0x30/0x30 [md_mod] ? kthread+0x115/0x140 ? __kthread_bind_mask+0x60/0x60 ? ret_from_fork+0x1f/0x40 mdadm D 0 5423 1 0x00004004 Call Trace: __schedule+0x1f6/0x560 ? __schedule+0x1fe/0x560 ? schedule+0x4a/0xb0 ? lock_comm.isra.0+0x7b/0xb0 [md_cluster] ? wait_woken+0x80/0x80 ? remove_disk+0x4f/0x90 [md_cluster] ? hot_remove_disk+0xb1/0x1b0 [md_mod] ? md_ioctl+0x50c/0xba0 [md_mod] ? wait_woken+0x80/0x80 ? blkdev_ioctl+0xa2/0x2a0 ? block_ioctl+0x39/0x40 ? ksys_ioctl+0x82/0xc0 ? __x64_sys_ioctl+0x16/0x20 ? do_syscall_64+0x5f/0x150 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 md0_resync D 0 5425 2 0x80004000 Call Trace: __schedule+0x1f6/0x560 ? schedule+0x4a/0xb0 ? dlm_lock_sync+0xa1/0xd0 [md_cluster] ? wait_woken+0x80/0x80 ? lock_token+0x2d/0x90 [md_cluster] ? resync_info_update+0x95/0x100 [md_cluster] ? raid1_sync_request+0x7d3/0xa40 [raid1] ? md_do_sync.cold+0x737/0xc8f [md_mod] ? md_thread+0x94/0x160 [md_mod] ? md_congested+0x30/0x30 [md_mod] ? kthread+0x115/0x140 ? __kthread_bind_mask+0x60/0x60 ? ret_from_fork+0x1f/0x40 ``` At last, thanks for Xiao's solution. Cc: stable@vger.kernel.org Signed-off-by: Zhao Heming Suggested-by: Xiao Ni Reviewed-by: Xiao Ni Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman

dm ioctl: fix error return code in target_message

2020-12-29T12:46:58+00:00
[ Upstream commit 4d7659bfbe277a43399a4a2d90fca141e70f29e1 ] Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function. Fixes: 2ca4c92f58f9 ("dm ioctl: prevent empty message") Reported-by: Hulk Robot Signed-off-by: Qinglang Miao Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

md: fix a warning caused by a race between concurrent md_ioctl()s

2020-12-29T12:46:50+00:00
commit c731b84b51bf7fe83448bea8f56a6d55006b0615 upstream. Syzkaller reports a warning as belows. WARNING: CPU: 0 PID: 9647 at drivers/md/md.c:7169 ... Call Trace: ... RIP: 0010:md_ioctl+0x4017/0x5980 drivers/md/md.c:7169 RSP: 0018:ffff888096027950 EFLAGS: 00010293 RAX: ffff88809322c380 RBX: 0000000000000932 RCX: ffffffff84e266f2 RDX: 0000000000000000 RSI: ffffffff84e299f7 RDI: 0000000000000007 RBP: ffff888096027bc0 R08: ffff88809322c380 R09: ffffed101341a482 R10: ffff888096027940 R11: ffff88809a0d240f R12: 0000000000000932 R13: ffff8880a2c14100 R14: ffff88809a0d2268 R15: ffff88809a0d2408 __blkdev_driver_ioctl block/ioctl.c:304 [inline] blkdev_ioctl+0xece/0x1c10 block/ioctl.c:606 block_ioctl+0xee/0x130 fs/block_dev.c:1930 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe This is caused by a race between two concurrenct md_ioctl()s closing the array. CPU1 (md_ioctl()) CPU2 (md_ioctl()) ------ ------ set_bit(MD_CLOSING, &mddev->flags); did_set_md_closing = true; WARN_ON_ONCE(test_bit(MD_CLOSING, &mddev->flags)); if(did_set_md_closing) clear_bit(MD_CLOSING, &mddev->flags); Fix the warning by returning immediately if the MD_CLOSING bit is set in &mddev->flags which indicates that the array is being closed. Fixes: 065e519e71b2 ("md: MD_CLOSING needs to be cleared after called md_set_readonly or do_md_stop") Reported-by: syzbot+1e46a0864c1a6e9bd3d8@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Dae R. Jeong Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman

dm table: Remove BUG_ON(in_interrupt())

2020-12-29T12:46:48+00:00
[ Upstream commit e7b624183d921b49ef0a96329f21647d38865ee9 ] The BUG_ON(in_interrupt()) in dm_table_event() is a historic leftover from a rework of the dm table code which changed the calling context. Issuing a BUG for a wrong calling context is frowned upon and in_interrupt() is deprecated and only covering parts of the wrong contexts. The sanity check for the context is covered by CONFIG_DEBUG_ATOMIC_SLEEP and other debug facilities already. Signed-off-by: Thomas Gleixner Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

md/raid5: fix oops during stripe resizing

2020-11-05T10:06:58+00:00
commit b44c018cdf748b96b676ba09fdbc5b34fc443ada upstream. KoWei reported crash during raid5 reshape: [ 1032.252932] Oops: 0002 [#1] SMP PTI [...] [ 1032.252943] RIP: 0010:memcpy_erms+0x6/0x10 [...] [ 1032.252947] RSP: 0018:ffffba1ac0c03b78 EFLAGS: 00010286 [ 1032.252949] RAX: 0000784ac0000000 RBX: ffff91bec3d09740 RCX: 0000000000001000 [ 1032.252951] RDX: 0000000000001000 RSI: ffff91be6781c000 RDI: 0000784ac0000000 [ 1032.252953] RBP: ffffba1ac0c03bd8 R08: 0000000000001000 R09: ffffba1ac0c03bf8 [ 1032.252954] R10: 0000000000000000 R11: 0000000000000000 R12: ffffba1ac0c03bf8 [ 1032.252955] R13: 0000000000001000 R14: 0000000000000000 R15: 0000000000000000 [ 1032.252958] FS: 0000000000000000(0000) GS:ffff91becf500000(0000) knlGS:0000000000000000 [ 1032.252959] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1032.252961] CR2: 0000784ac0000000 CR3: 000000031780a002 CR4: 00000000001606e0 [ 1032.252962] Call Trace: [ 1032.252969] ? async_memcpy+0x179/0x1000 [async_memcpy] [ 1032.252977] ? raid5_release_stripe+0x8e/0x110 [raid456] [ 1032.252982] handle_stripe_expansion+0x15a/0x1f0 [raid456] [ 1032.252988] handle_stripe+0x592/0x1270 [raid456] [ 1032.252993] handle_active_stripes.isra.0+0x3cb/0x5a0 [raid456] [ 1032.252999] raid5d+0x35c/0x550 [raid456] [ 1032.253002] ? schedule+0x42/0xb0 [ 1032.253006] ? schedule_timeout+0x10e/0x160 [ 1032.253011] md_thread+0x97/0x160 [ 1032.253015] ? wait_woken+0x80/0x80 [ 1032.253019] kthread+0x104/0x140 [ 1032.253022] ? md_start_sync+0x60/0x60 [ 1032.253024] ? kthread_park+0x90/0x90 [ 1032.253027] ret_from_fork+0x35/0x40 This is because cache_size_mutex was unlocked too early in resize_stripes, which races with grow_one_stripe() that grow_one_stripe() allocates a stripe with wrong pool_size. Fix this issue by unlocking cache_size_mutex after updating pool_size. Cc: # v4.4+ Reported-by: KoWei Sung Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman

md/bitmap: md_bitmap_get_counter returns wrong blocks

2020-11-05T10:06:56+00:00
[ Upstream commit d837f7277f56e70d82b3a4a037d744854e62f387 ] md_bitmap_get_counter() has code: ``` if (bitmap->bp[page].hijacked || bitmap->bp[page].map == NULL) csize = ((sector_t)1) << (bitmap->chunkshift + PAGE_COUNTER_SHIFT - 1); ``` The minus 1 is wrong, this branch should report 2048 bits of space. With "-1" action, this only report 1024 bit of space. This bug code returns wrong blocks, but it doesn't inflence bitmap logic: 1. Most callers focus this function return value (the counter of offset), not the parameter blocks. 2. The bug is only triggered when hijacked is true or map is NULL. the hijacked true condition is very rare. the "map == null" only true when array is creating or resizing. 3. Even the caller gets wrong blocks, current code makes caller just to call md_bitmap_get_counter() one more time. Signed-off-by: Zhao Heming Signed-off-by: Song Liu Signed-off-by: Sasha Levin