summaryrefslogtreecommitdiff
path: root/fs/btrfs
AgeCommit message (Collapse)Author
2019-10-29btrfs: block-group: Fix a memory leak due to missing btrfs_put_block_group()Qu Wenruo
commit 4b654acdae850f48b8250b9a578a4eaa518c7a6f upstream. In btrfs_read_block_groups(), if we have an invalid block group which has mixed type (DATA|METADATA) while the fs doesn't have MIXED_GROUPS feature, we error out without freeing the block group cache. This patch will add the missing btrfs_put_block_group() to prevent memory leak. Note for stable backports: the file to patch in versions <= 5.3 is fs/btrfs/extent-tree.c Fixes: 49303381f19a ("Btrfs: bail out if block group has different mixed flag") CC: stable@vger.kernel.org # 4.9+ Reviewed-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05Btrfs: fix race setting up and completing qgroup rescan workersFilipe Manana
[ Upstream commit 13fc1d271a2e3ab8a02071e711add01fab9271f6 ] There is a race between setting up a qgroup rescan worker and completing a qgroup rescan worker that can lead to callers of the qgroup rescan wait ioctl to either not wait for the rescan worker to complete or to hang forever due to missing wake ups. The following diagram shows a sequence of steps that illustrates the race. CPU 1 CPU 2 CPU 3 btrfs_ioctl_quota_rescan() btrfs_qgroup_rescan() qgroup_rescan_init() mutex_lock(&fs_info->qgroup_rescan_lock) spin_lock(&fs_info->qgroup_lock) fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN init_completion( &fs_info->qgroup_rescan_completion) fs_info->qgroup_rescan_running = true mutex_unlock(&fs_info->qgroup_rescan_lock) spin_unlock(&fs_info->qgroup_lock) btrfs_init_work() --> starts the worker btrfs_qgroup_rescan_worker() mutex_lock(&fs_info->qgroup_rescan_lock) fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN mutex_unlock(&fs_info->qgroup_rescan_lock) starts transaction, updates qgroup status item, etc btrfs_ioctl_quota_rescan() btrfs_qgroup_rescan() qgroup_rescan_init() mutex_lock(&fs_info->qgroup_rescan_lock) spin_lock(&fs_info->qgroup_lock) fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN init_completion( &fs_info->qgroup_rescan_completion) fs_info->qgroup_rescan_running = true mutex_unlock(&fs_info->qgroup_rescan_lock) spin_unlock(&fs_info->qgroup_lock) btrfs_init_work() --> starts another worker mutex_lock(&fs_info->qgroup_rescan_lock) fs_info->qgroup_rescan_running = false mutex_unlock(&fs_info->qgroup_rescan_lock) complete_all(&fs_info->qgroup_rescan_completion) Before the rescan worker started by the task at CPU 3 completes, if another task calls btrfs_ioctl_quota_rescan(), it will get -EINPROGRESS because the flag BTRFS_QGROUP_STATUS_FLAG_RESCAN is set at fs_info->qgroup_flags, which is expected and correct behaviour. However if other task calls btrfs_ioctl_quota_rescan_wait() before the rescan worker started by the task at CPU 3 completes, it will return immediately without waiting for the new rescan worker to complete, because fs_info->qgroup_rescan_running is set to false by CPU 2. This race is making test case btrfs/171 (from fstests) to fail often: btrfs/171 9s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/171.out.bad) # --- tests/btrfs/171.out 2018-09-16 21:30:48.505104287 +0100 # +++ /home/fdmanana/git/hub/xfstests/results//btrfs/171.out.bad 2019-09-19 02:01:36.938486039 +0100 # @@ -1,2 +1,3 @@ # QA output created by 171 # +ERROR: quota rescan failed: Operation now in progress # Silence is golden # ... # (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/btrfs/171.out /home/fdmanana/git/hub/xfstests/results//btrfs/171.out.bad' to see the entire diff) That is because the test calls the btrfs-progs commands "qgroup quota rescan -w", "qgroup assign" and "qgroup remove" in a sequence that makes calls to the rescan start ioctl fail with -EINPROGRESS (note the "btrfs" commands 'qgroup assign' and 'qgroup remove' often call the rescan start ioctl after calling the qgroup assign ioctl, btrfs_ioctl_qgroup_assign()), since previous waits didn't actually wait for a rescan worker to complete. Another problem the race can cause is missing wake ups for waiters, since the call to complete_all() happens outside a critical section and after clearing the flag BTRFS_QGROUP_STATUS_FLAG_RESCAN. In the sequence diagram above, if we have a waiter for the first rescan task (executed by CPU 2), then fs_info->qgroup_rescan_completion.wait is not empty, and if after the rescan worker clears BTRFS_QGROUP_STATUS_FLAG_RESCAN and before it calls complete_all() against fs_info->qgroup_rescan_completion, the task at CPU 3 calls init_completion() against fs_info->qgroup_rescan_completion which re-initilizes its wait queue to an empty queue, therefore causing the rescan worker at CPU 2 to call complete_all() against an empty queue, never waking up the task waiting for that rescan worker. Fix this by clearing BTRFS_QGROUP_STATUS_FLAG_RESCAN and setting fs_info->qgroup_rescan_running to false in the same critical section, delimited by the mutex fs_info->qgroup_rescan_lock, as well as doing the call to complete_all() in that same critical section. This gives the protection needed to avoid rescan wait ioctl callers not waiting for a running rescan worker and the lost wake ups problem, since setting that rescan flag and boolean as well as initializing the wait queue is done already in a critical section delimited by that mutex (at qgroup_rescan_init()). Fixes: 57254b6ebce4ce ("Btrfs: add ioctl to wait for qgroup rescan completion") Fixes: d2c609b834d62f ("btrfs: properly track when rescan worker is running") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05btrfs: qgroup: Drop quota_root and fs_info parameters from ↵Lu Fengqi
update_qgroup_status_item [ Upstream commit 2e980acdd829742966c6a7e565ef3382c0717295 ] They can be fetched from the transaction handle. Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05btrfs: Relinquish CPUs in btrfs_compare_treesNikolay Borisov
commit 6af112b11a4bc1b560f60a618ac9c1dcefe9836e upstream. When doing any form of incremental send the parent and the child trees need to be compared via btrfs_compare_trees. This can result in long loop chains without ever relinquishing the CPU. This causes softlockup detector to trigger when comparing trees with a lot of items. Example report: watchdog: BUG: soft lockup - CPU#0 stuck for 24s! [snapperd:16153] CPU: 0 PID: 16153 Comm: snapperd Not tainted 5.2.9-1-default #1 openSUSE Tumbleweed (unreleased) Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 40000005 (nZcv daif -PAN -UAO) pc : __ll_sc_arch_atomic_sub_return+0x14/0x20 lr : btrfs_release_extent_buffer_pages+0xe0/0x1e8 [btrfs] sp : ffff00001273b7e0 Call trace: __ll_sc_arch_atomic_sub_return+0x14/0x20 release_extent_buffer+0xdc/0x120 [btrfs] free_extent_buffer.part.0+0xb0/0x118 [btrfs] free_extent_buffer+0x24/0x30 [btrfs] btrfs_release_path+0x4c/0xa0 [btrfs] btrfs_free_path.part.0+0x20/0x40 [btrfs] btrfs_free_path+0x24/0x30 [btrfs] get_inode_info+0xa8/0xf8 [btrfs] finish_inode_if_needed+0xe0/0x6d8 [btrfs] changed_cb+0x9c/0x410 [btrfs] btrfs_compare_trees+0x284/0x648 [btrfs] send_subvol+0x33c/0x520 [btrfs] btrfs_ioctl_send+0x8a0/0xaf0 [btrfs] btrfs_ioctl+0x199c/0x2288 [btrfs] do_vfs_ioctl+0x4b0/0x820 ksys_ioctl+0x84/0xb8 __arm64_sys_ioctl+0x28/0x38 el0_svc_common.constprop.0+0x7c/0x188 el0_svc_handler+0x34/0x90 el0_svc+0x8/0xc Fix this by adding a call to cond_resched at the beginning of the main loop in btrfs_compare_trees. Fixes: 7069830a9e38 ("Btrfs: add btrfs_compare_trees function") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05Btrfs: fix use-after-free when using the tree modification logFilipe Manana
commit efad8a853ad2057f96664328a0d327a05ce39c76 upstream. At ctree.c:get_old_root(), we are accessing a root's header owner field after we have freed the respective extent buffer. This results in an use-after-free that can lead to crashes, and when CONFIG_DEBUG_PAGEALLOC is set, results in a stack trace like the following: [ 3876.799331] stack segment: 0000 [#1] SMP DEBUG_PAGEALLOC PTI [ 3876.799363] CPU: 0 PID: 15436 Comm: pool Not tainted 5.3.0-rc3-btrfs-next-54 #1 [ 3876.799385] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 [ 3876.799433] RIP: 0010:btrfs_search_old_slot+0x652/0xd80 [btrfs] (...) [ 3876.799502] RSP: 0018:ffff9f08c1a2f9f0 EFLAGS: 00010286 [ 3876.799518] RAX: ffff8dd300000000 RBX: ffff8dd85a7a9348 RCX: 000000038da26000 [ 3876.799538] RDX: 0000000000000000 RSI: ffffe522ce368980 RDI: 0000000000000246 [ 3876.799559] RBP: dae1922adadad000 R08: 0000000008020000 R09: ffffe522c0000000 [ 3876.799579] R10: ffff8dd57fd788c8 R11: 000000007511b030 R12: ffff8dd781ddc000 [ 3876.799599] R13: ffff8dd9e6240578 R14: ffff8dd6896f7a88 R15: ffff8dd688cf90b8 [ 3876.799620] FS: 00007f23ddd97700(0000) GS:ffff8dda20200000(0000) knlGS:0000000000000000 [ 3876.799643] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3876.799660] CR2: 00007f23d4024000 CR3: 0000000710bb0005 CR4: 00000000003606f0 [ 3876.799682] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3876.799703] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3876.799723] Call Trace: [ 3876.799735] ? do_raw_spin_unlock+0x49/0xc0 [ 3876.799749] ? _raw_spin_unlock+0x24/0x30 [ 3876.799779] resolve_indirect_refs+0x1eb/0xc80 [btrfs] [ 3876.799810] find_parent_nodes+0x38d/0x1180 [btrfs] [ 3876.799841] btrfs_check_shared+0x11a/0x1d0 [btrfs] [ 3876.799870] ? extent_fiemap+0x598/0x6e0 [btrfs] [ 3876.799895] extent_fiemap+0x598/0x6e0 [btrfs] [ 3876.799913] do_vfs_ioctl+0x45a/0x700 [ 3876.799926] ksys_ioctl+0x70/0x80 [ 3876.799938] ? trace_hardirqs_off_thunk+0x1a/0x20 [ 3876.799953] __x64_sys_ioctl+0x16/0x20 [ 3876.799965] do_syscall_64+0x62/0x220 [ 3876.799977] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 3876.799993] RIP: 0033:0x7f23e0013dd7 (...) [ 3876.800056] RSP: 002b:00007f23ddd96ca8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 3876.800078] RAX: ffffffffffffffda RBX: 00007f23d80210f8 RCX: 00007f23e0013dd7 [ 3876.800099] RDX: 00007f23d80210f8 RSI: 00000000c020660b RDI: 0000000000000003 [ 3876.800626] RBP: 000055fa2a2a2440 R08: 0000000000000000 R09: 00007f23ddd96d7c [ 3876.801143] R10: 00007f23d8022000 R11: 0000000000000246 R12: 00007f23ddd96d80 [ 3876.801662] R13: 00007f23ddd96d78 R14: 00007f23d80210f0 R15: 00007f23ddd96d80 (...) [ 3876.805107] ---[ end trace e53161e179ef04f9 ]--- Fix that by saving the root's header owner field into a local variable before freeing the root's extent buffer, and then use that local variable when needed. Fixes: 30b0463a9394d9 ("Btrfs: fix accessing the root pointer in tree mod log functions") CC: stable@vger.kernel.org # 3.10+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05btrfs: extent-tree: Make sure we only allocate extents from block groups ↵Qu Wenruo
with the same type [ Upstream commit 2a28468e525f3924efed7f29f2bc5a2926e7e19a ] [BUG] With fuzzed image and MIXED_GROUPS super flag, we can hit the following BUG_ON(): kernel BUG at fs/btrfs/delayed-ref.c:491! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 1849 Comm: sync Tainted: G O 5.2.0-custom #27 RIP: 0010:update_existing_head_ref.cold+0x44/0x46 [btrfs] Call Trace: add_delayed_ref_head+0x20c/0x2d0 [btrfs] btrfs_add_delayed_tree_ref+0x1fc/0x490 [btrfs] btrfs_free_tree_block+0x123/0x380 [btrfs] __btrfs_cow_block+0x435/0x500 [btrfs] btrfs_cow_block+0x110/0x240 [btrfs] btrfs_search_slot+0x230/0xa00 [btrfs] ? __lock_acquire+0x105e/0x1e20 btrfs_insert_empty_items+0x67/0xc0 [btrfs] alloc_reserved_file_extent+0x9e/0x340 [btrfs] __btrfs_run_delayed_refs+0x78e/0x1240 [btrfs] ? kvm_clock_read+0x18/0x30 ? __sched_clock_gtod_offset+0x21/0x50 btrfs_run_delayed_refs.part.0+0x4e/0x180 [btrfs] btrfs_run_delayed_refs+0x23/0x30 [btrfs] btrfs_commit_transaction+0x53/0x9f0 [btrfs] btrfs_sync_fs+0x7c/0x1c0 [btrfs] ? __ia32_sys_fdatasync+0x20/0x20 sync_fs_one_sb+0x23/0x30 iterate_supers+0x95/0x100 ksys_sync+0x62/0xb0 __ia32_sys_sync+0xe/0x20 do_syscall_64+0x65/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe [CAUSE] This situation is caused by several factors: - Fuzzed image The extent tree of this fs missed one backref for extent tree root. So we can allocated space from that slot. - MIXED_BG feature Super block has MIXED_BG flag. - No mixed block groups exists All block groups are just regular ones. This makes data space_info->block_groups[] contains metadata block groups. And when we reserve space for data, we can use space in metadata block group. Then we hit the following file operations: - fallocate We need to allocate data extents. find_free_extent() choose to use the metadata block to allocate space from, and choose the space of extent tree root, since its backref is missing. This generate one delayed ref head with is_data = 1. - extent tree update We need to update extent tree at run_delayed_ref time. This generate one delayed ref head with is_data = 0, for the same bytenr of old extent tree root. Then we trigger the BUG_ON(). [FIX] The quick fix here is to check block_group->flags before using it. The problem can only happen for MIXED_GROUPS fs. Regular filesystems won't have space_info with DATA|METADATA flag, and no way to hit the bug. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203255 Reported-by: Jungyeon Yoon <jungyeon.yoon@gmail.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-21Btrfs: fix assertion failure during fsync and use of stale transactionFilipe Manana
commit 410f954cb1d1c79ae485dd83a175f21954fd87cd upstream. Sometimes when fsync'ing a file we need to log that other inodes exist and when we need to do that we acquire a reference on the inodes and then drop that reference using iput() after logging them. That generally is not a problem except if we end up doing the final iput() (dropping the last reference) on the inode and that inode has a link count of 0, which can happen in a very short time window if the logging path gets a reference on the inode while it's being unlinked. In that case we end up getting the eviction callback, btrfs_evict_inode(), invoked through the iput() call chain which needs to drop all of the inode's items from its subvolume btree, and in order to do that, it needs to join a transaction at the helper function evict_refill_and_join(). However because the task previously started a transaction at the fsync handler, btrfs_sync_file(), it has current->journal_info already pointing to a transaction handle and therefore evict_refill_and_join() will get that transaction handle from btrfs_join_transaction(). From this point on, two different problems can happen: 1) evict_refill_and_join() will often change the transaction handle's block reserve (->block_rsv) and set its ->bytes_reserved field to a value greater than 0. If evict_refill_and_join() never commits the transaction, the eviction handler ends up decreasing the reference count (->use_count) of the transaction handle through the call to btrfs_end_transaction(), and after that point we have a transaction handle with a NULL ->block_rsv (which is the value prior to the transaction join from evict_refill_and_join()) and a ->bytes_reserved value greater than 0. If after the eviction/iput completes the inode logging path hits an error or it decides that it must fallback to a transaction commit, the btrfs fsync handle, btrfs_sync_file(), gets a non-zero value from btrfs_log_dentry_safe(), and because of that non-zero value it tries to commit the transaction using a handle with a NULL ->block_rsv and a non-zero ->bytes_reserved value. This makes the transaction commit hit an assertion failure at btrfs_trans_release_metadata() because ->bytes_reserved is not zero but the ->block_rsv is NULL. The produced stack trace for that is like the following: [192922.917158] assertion failed: !trans->bytes_reserved, file: fs/btrfs/transaction.c, line: 816 [192922.917553] ------------[ cut here ]------------ [192922.917922] kernel BUG at fs/btrfs/ctree.h:3532! [192922.918310] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI [192922.918666] CPU: 2 PID: 883 Comm: fsstress Tainted: G W 5.1.4-btrfs-next-47 #1 [192922.919035] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [192922.919801] RIP: 0010:assfail.constprop.25+0x18/0x1a [btrfs] (...) [192922.920925] RSP: 0018:ffffaebdc8a27da8 EFLAGS: 00010286 [192922.921315] RAX: 0000000000000051 RBX: ffff95c9c16a41c0 RCX: 0000000000000000 [192922.921692] RDX: 0000000000000000 RSI: ffff95cab6b16838 RDI: ffff95cab6b16838 [192922.922066] RBP: ffff95c9c16a41c0 R08: 0000000000000000 R09: 0000000000000000 [192922.922442] R10: ffffaebdc8a27e70 R11: 0000000000000000 R12: ffff95ca731a0980 [192922.922820] R13: 0000000000000000 R14: ffff95ca84c73338 R15: ffff95ca731a0ea8 [192922.923200] FS: 00007f337eda4e80(0000) GS:ffff95cab6b00000(0000) knlGS:0000000000000000 [192922.923579] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [192922.923948] CR2: 00007f337edad000 CR3: 00000001e00f6002 CR4: 00000000003606e0 [192922.924329] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [192922.924711] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [192922.925105] Call Trace: [192922.925505] btrfs_trans_release_metadata+0x10c/0x170 [btrfs] [192922.925911] btrfs_commit_transaction+0x3e/0xaf0 [btrfs] [192922.926324] btrfs_sync_file+0x44c/0x490 [btrfs] [192922.926731] do_fsync+0x38/0x60 [192922.927138] __x64_sys_fdatasync+0x13/0x20 [192922.927543] do_syscall_64+0x60/0x1c0 [192922.927939] entry_SYSCALL_64_after_hwframe+0x49/0xbe (...) [192922.934077] ---[ end trace f00808b12068168f ]--- 2) If evict_refill_and_join() decides to commit the transaction, it will be able to do it, since the nested transaction join only increments the transaction handle's ->use_count reference counter and it does not prevent the transaction from getting committed. This means that after eviction completes, the fsync logging path will be using a transaction handle that refers to an already committed transaction. What happens when using such a stale transaction can be unpredictable, we are at least having a use-after-free on the transaction handle itself, since the transaction commit will call kmem_cache_free() against the handle regardless of its ->use_count value, or we can end up silently losing all the updates to the log tree after that iput() in the logging path, or using a transaction handle that in the meanwhile was allocated to another task for a new transaction, etc, pretty much unpredictable what can happen. In order to fix both of them, instead of using iput() during logging, use btrfs_add_delayed_iput(), so that the logging path of fsync never drops the last reference on an inode, that step is offloaded to a safe context (usually the cleaner kthread). The assertion failure issue was sporadically triggered by the test case generic/475 from fstests, which loads the dm error target while fsstress is running, which lead to fsync failing while logging inodes with -EIO errors and then trying later to commit the transaction, triggering the assertion failure. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-06Btrfs: fix incremental send failure after deduplicationFilipe Manana
commit b4f9a1a87a48c255bb90d8a6c3d555a1abb88130 upstream. When doing an incremental send operation we can fail if we previously did deduplication operations against a file that exists in both snapshots. In that case we will fail the send operation with -EIO and print a message to dmesg/syslog like the following: BTRFS error (device sdc): Send: inconsistent snapshot, found updated \ extent for inode 257 without updated inode item, send root is 258, \ parent root is 257 This requires that we deduplicate to the same file in both snapshots for the same amount of times on each snapshot. The issue happens because a deduplication only updates the iversion of an inode and does not update any other field of the inode, therefore if we deduplicate the file on each snapshot for the same amount of time, the inode will have the same iversion value (stored as the "sequence" field on the inode item) on both snapshots, therefore it will be seen as unchanged between in the send snapshot while there are new/updated/deleted extent items when comparing to the parent snapshot. This makes the send operation return -EIO and print an error message. Example reproducer: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt # Create our first file. The first half of the file has several 64Kb # extents while the second half as a single 512Kb extent. $ xfs_io -f -s -c "pwrite -S 0xb8 -b 64K 0 512K" /mnt/foo $ xfs_io -c "pwrite -S 0xb8 512K 512K" /mnt/foo # Create the base snapshot and the parent send stream from it. $ btrfs subvolume snapshot -r /mnt /mnt/mysnap1 $ btrfs send -f /tmp/1.snap /mnt/mysnap1 # Create our second file, that has exactly the same data as the first # file. $ xfs_io -f -c "pwrite -S 0xb8 0 1M" /mnt/bar # Create the second snapshot, used for the incremental send, before # doing the file deduplication. $ btrfs subvolume snapshot -r /mnt /mnt/mysnap2 # Now before creating the incremental send stream: # # 1) Deduplicate into a subrange of file foo in snapshot mysnap1. This # will drop several extent items and add a new one, also updating # the inode's iversion (sequence field in inode item) by 1, but not # any other field of the inode; # # 2) Deduplicate into a different subrange of file foo in snapshot # mysnap2. This will replace an extent item with a new one, also # updating the inode's iversion by 1 but not any other field of the # inode. # # After these two deduplication operations, the inode items, for file # foo, are identical in both snapshots, but we have different extent # items for this inode in both snapshots. We want to check this doesn't # cause send to fail with an error or produce an incorrect stream. $ xfs_io -r -c "dedupe /mnt/bar 0 0 512K" /mnt/mysnap1/foo $ xfs_io -r -c "dedupe /mnt/bar 512K 512K 512K" /mnt/mysnap2/foo # Create the incremental send stream. $ btrfs send -p /mnt/mysnap1 -f /tmp/2.snap /mnt/mysnap2 ERROR: send ioctl failed with -5: Input/output error This issue started happening back in 2015 when deduplication was updated to not update the inode's ctime and mtime and update only the iversion. Back then we would hit a BUG_ON() in send, but later in 2016 send was updated to return -EIO and print the error message instead of doing the BUG_ON(). A test case for fstests follows soon. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203933 Fixes: 1c919a5e13702c ("btrfs: don't update mtime/ctime on deduped inodes") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-06btrfs: fix minimum number of chunk errors for DUPDavid Sterba
[ Upstream commit 0ee5f8ae082e1f675a2fb6db601c31ac9958a134 ] The list of profiles in btrfs_chunk_max_errors lists DUP as a profile DUP able to tolerate 1 device missing. Though this profile is special with 2 copies, it still needs the device, unlike the others. Looking at the history of changes, thre's no clear reason why DUP is there, functions were refactored and blocks of code merged to one helper. d20983b40e828 Btrfs: fix writing data into the seed filesystem - factor code to a helper de11cc12df173 Btrfs: don't pre-allocate btrfs bio - unrelated change, DUP still in the list with max errors 1 a236aed14ccb0 Btrfs: Deal with failed writes in mirrored configurations - introduced the max errors, leaves DUP and RAID1 in the same group Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04Btrfs: add missing inode version, ctime and mtime updates when punching holeFilipe Manana
commit 179006688a7e888cbff39577189f2e034786d06a upstream. If the range for which we are punching a hole covers only part of a page, we end up updating the inode item but we skip the update of the inode's iversion, mtime and ctime. Fix that by ensuring we update those properties of the inode. A patch for fstests test case generic/059 that tests this as been sent along with this fix. Fixes: 2aaa66558172b0 ("Btrfs: add hole punching") Fixes: e8c1c76e804b18 ("Btrfs: add missing inode update when punching hole") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10btrfs: Ensure replaced device doesn't have pending chunk allocationNikolay Borisov
commit debd1c065d2037919a7da67baf55cc683fee09f0 upstream. Recent FITRIM work, namely bbbf7243d62d ("btrfs: combine device update operations during transaction commit") combined the way certain operations are recoded in a transaction. As a result an ASSERT was added in dev_replace_finish to ensure the new code works correctly. Unfortunately I got reports that it's possible to trigger the assert, meaning that during a device replace it's possible to have an unfinished chunk allocation on the source device. This is supposed to be prevented by the fact that a transaction is committed before finishing the replace oepration and alter acquiring the chunk mutex. This is not sufficient since by the time the transaction is committed and the chunk mutex acquired it's possible to allocate a chunk depending on the workload being executed on the replaced device. This bug has been present ever since device replace was introduced but there was never code which checks for it. The correct way to fix is to ensure that there is no pending device modification operation when the chunk mutex is acquire and if there is repeat transaction commit. Unfortunately it's not possible to just exclude the source device from btrfs_fs_devices::dev_alloc_list since this causes ENOSPC to be hit in transaction commit. Fixing that in another way would need to add special cases to handle the last writes and forbid new ones. The looped transaction fix is more obvious, and can be easily backported. The runtime of dev-replace is long so there's no noticeable delay caused by that. Reported-by: David Sterba <dsterba@suse.com> Fixes: 391cd9df81ac ("Btrfs: fix unprotected alloc list insertion during the finishing procedure of replace") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10btrfs: start readahead also in seed devicesNaohiro Aota
commit c4e0540d0ad49c8ceab06cceed1de27c4fe29f6e upstream. Currently, btrfs does not consult seed devices to start readahead. As a result, if readahead zone is added to the seed devices, btrfs_reada_wait() indefinitely wait for the reada_ctl to finish. You can reproduce the hung by modifying btrfs/163 to have larger initial file size (e.g. xfs_io pwrite 4M instead of current 256K). Fixes: 7414a03fbf9e ("btrfs: initial readahead code and prototypes") Cc: stable@vger.kernel.org # 3.2+: ce7791ffee1e: Btrfs: fix race between readahead and device replace/removal Cc: stable@vger.kernel.org # 3.2+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11Btrfs: fix race updating log root item during fsyncFilipe Manana
commit 06989c799f04810f6876900d4760c0edda369cf7 upstream. When syncing the log, the final phase of a fsync operation, we need to either create a log root's item or update the existing item in the log tree of log roots, and that depends on the current value of the log root's log_transid - if it's 1 we need to create the log root item, otherwise it must exist already and we update it. Since there is no synchronization between updating the log_transid and checking it for deciding whether the log root's item needs to be created or updated, we end up with a tiny race window that results in attempts to update the item to fail because the item was not yet created: CPU 1 CPU 2 btrfs_sync_log() lock root->log_mutex set log root's log_transid to 1 unlock root->log_mutex btrfs_sync_log() lock root->log_mutex sets log root's log_transid to 2 unlock root->log_mutex update_log_root() sees log root's log_transid with a value of 2 calls btrfs_update_root(), which fails with -EUCLEAN and causes transaction abort Until recently the race lead to a BUG_ON at btrfs_update_root(), but after the recent commit 7ac1e464c4d47 ("btrfs: Don't panic when we can't find a root key") we just abort the current transaction. A sample trace of the BUG_ON() on a SLE12 kernel: ------------[ cut here ]------------ kernel BUG at ../fs/btrfs/root-tree.c:157! Oops: Exception in kernel mode, sig: 5 [#1] SMP NR_CPUS=2048 NUMA pSeries (...) Supported: Yes, External CPU: 78 PID: 76303 Comm: rtas_errd Tainted: G X 4.4.156-94.57-default #1 task: c00000ffa906d010 ti: c00000ff42b08000 task.ti: c00000ff42b08000 NIP: d000000036ae5cdc LR: d000000036ae5cd8 CTR: 0000000000000000 REGS: c00000ff42b0b860 TRAP: 0700 Tainted: G X (4.4.156-94.57-default) MSR: 8000000002029033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 22444484 XER: 20000000 CFAR: d000000036aba66c SOFTE: 1 GPR00: d000000036ae5cd8 c00000ff42b0bae0 d000000036bda220 0000000000000054 GPR04: 0000000000000001 0000000000000000 c00007ffff8d37c8 0000000000000000 GPR08: c000000000e19c00 0000000000000000 0000000000000000 3736343438312079 GPR12: 3930373337303434 c000000007a3a800 00000000007fffff 0000000000000023 GPR16: c00000ffa9d26028 c00000ffa9d261f8 0000000000000010 c00000ffa9d2ab28 GPR20: c00000ff42b0bc48 0000000000000001 c00000ff9f0d9888 0000000000000001 GPR24: c00000ffa9d26000 c00000ffa9d261e8 c00000ffa9d2a800 c00000ff9f0d9888 GPR28: c00000ffa9d26028 c00000ffa9d2aa98 0000000000000001 c00000ffa98f5b20 NIP [d000000036ae5cdc] btrfs_update_root+0x25c/0x4e0 [btrfs] LR [d000000036ae5cd8] btrfs_update_root+0x258/0x4e0 [btrfs] Call Trace: [c00000ff42b0bae0] [d000000036ae5cd8] btrfs_update_root+0x258/0x4e0 [btrfs] (unreliable) [c00000ff42b0bba0] [d000000036b53610] btrfs_sync_log+0x2d0/0xc60 [btrfs] [c00000ff42b0bce0] [d000000036b1785c] btrfs_sync_file+0x44c/0x4e0 [btrfs] [c00000ff42b0bd80] [c00000000032e300] vfs_fsync_range+0x70/0x120 [c00000ff42b0bdd0] [c00000000032e44c] do_fsync+0x5c/0xb0 [c00000ff42b0be10] [c00000000032e8dc] SyS_fdatasync+0x2c/0x40 [c00000ff42b0be30] [c000000000009488] system_call+0x3c/0x100 Instruction dump: 7f43d378 4bffebb9 60000000 88d90008 3d220000 e8b90000 3b390009 e87a01f0 e8898e08 e8f90000 4bfd48e5 60000000 <0fe00000> e95b0060 39200004 394a0ea0 ---[ end trace 8f2dc8f919cabab8 ]--- So fix this by doing the check of log_transid and updating or creating the log root's item while holding the root's log_mutex. Fixes: 7237f1833601d ("Btrfs: fix tree logs parallel sync") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31Revert "btrfs: Honour FITRIM range constraints during free space trim"David Sterba
This reverts commit 038ec2c13e0d1f7b9d45a081786f18f75b65f11b. There is currently no corresponding patch in master due to additional changes that would be significantly different from plain revert in the respective stable branch. The range argument was not handled correctly and could cause trim to overlap allocated areas or reach beyond the end of the device. The address space that fitrim normally operates on is in logical coordinates, while the discards are done on the physical device extents. This distinction cannot be made with the current ioctl interface and caused the confusion. The bug depends on the layout of block groups and does not always happen. The whole-fs trim (run by default by the fstrim tool) is not affected. Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31btrfs: sysfs: don't leak memory when failing add fsidTobin C. Harding
commit e32773357d5cc271b1d23550b3ed026eb5c2a468 upstream. A failed call to kobject_init_and_add() must be followed by a call to kobject_put(). Currently in the error path when adding fs_devices we are missing this call. This could be fixed by calling btrfs_sysfs_remove_fsid() if btrfs_sysfs_add_fsid() returns an error or by adding a call to kobject_put() directly in btrfs_sysfs_add_fsid(). Here we choose the second option because it prevents the slightly unusual error path handling requirements of kobject from leaking out into btrfs functions. Add a call to kobject_put() in the error path of kobject_add_and_init(). This causes the release method to be called if kobject_init_and_add() fails. open_tree() is the function that calls btrfs_sysfs_add_fsid() and the error code in this function is already written with the assumption that the release method is called during the error path of open_tree() (as seen by the call to btrfs_sysfs_remove_fsid() under the fail_fsdev_sysfs label). Cc: stable@vger.kernel.org # v4.4+ Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tobin C. Harding <tobin@kernel.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31Btrfs: fix race between ranged fsync and writeback of adjacent rangesFilipe Manana
commit 0c713cbab6200b0ab6473b50435e450a6e1de85d upstream. When we do a full fsync (the bit BTRFS_INODE_NEEDS_FULL_SYNC is set in the inode) that happens to be ranged, which happens during a msync() or writes for files opened with O_SYNC for example, we can end up with a corrupt log, due to different file extent items representing ranges that overlap with each other, or hit some assertion failures. When doing a ranged fsync we only flush delalloc and wait for ordered exents within that range. If while we are logging items from our inode ordered extents for adjacent ranges complete, we end up in a race that can make us insert the file extent items that overlap with others we logged previously and the assertion failures. For example, if tree-log.c:copy_items() receives a leaf that has the following file extents items, all with a length of 4K and therefore there is an implicit hole in the range 68K to 72K - 1: (257 EXTENT_ITEM 64K), (257 EXTENT_ITEM 72K), (257 EXTENT_ITEM 76K), ... It copies them to the log tree. However due to the need to detect implicit holes, it may release the path, in order to look at the previous leaf to detect an implicit hole, and then later it will search again in the tree for the first file extent item key, with the goal of locking again the leaf (which might have changed due to concurrent changes to other inodes). However when it locks again the leaf containing the first key, the key corresponding to the extent at offset 72K may not be there anymore since there is an ordered extent for that range that is finishing (that is, somewhere in the middle of btrfs_finish_ordered_io()), and it just removed the file extent item but has not yet replaced it with a new file extent item, so the part of copy_items() that does hole detection will decide that there is a hole in the range starting from 68K to 76K - 1, and therefore insert a file extent item to represent that hole, having a key offset of 68K. After that we now have a log tree with 2 different extent items that have overlapping ranges: 1) The file extent item copied before copy_items() released the path, which has a key offset of 72K and a length of 4K, representing the file range 72K to 76K - 1. 2) And a file extent item representing a hole that has a key offset of 68K and a length of 8K, representing the range 68K to 76K - 1. This item was inserted after releasing the path, and overlaps with the extent item inserted before. The overlapping extent items can cause all sorts of unpredictable and incorrect behaviour, either when replayed or if a fast (non full) fsync happens later, which can trigger a BUG_ON() when calling btrfs_set_item_key_safe() through __btrfs_drop_extents(), producing a trace like the following: [61666.783269] ------------[ cut here ]------------ [61666.783943] kernel BUG at fs/btrfs/ctree.c:3182! [61666.784644] invalid opcode: 0000 [#1] PREEMPT SMP (...) [61666.786253] task: ffff880117b88c40 task.stack: ffffc90008168000 [61666.786253] RIP: 0010:btrfs_set_item_key_safe+0x7c/0xd2 [btrfs] [61666.786253] RSP: 0018:ffffc9000816b958 EFLAGS: 00010246 [61666.786253] RAX: 0000000000000000 RBX: 000000000000000f RCX: 0000000000030000 [61666.786253] RDX: 0000000000000000 RSI: ffffc9000816ba4f RDI: ffffc9000816b937 [61666.786253] RBP: ffffc9000816b998 R08: ffff88011dae2428 R09: 0000000000001000 [61666.786253] R10: 0000160000000000 R11: 6db6db6db6db6db7 R12: ffff88011dae2418 [61666.786253] R13: ffffc9000816ba4f R14: ffff8801e10c4118 R15: ffff8801e715c000 [61666.786253] FS: 00007f6060a18700(0000) GS:ffff88023f5c0000(0000) knlGS:0000000000000000 [61666.786253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [61666.786253] CR2: 00007f6060a28000 CR3: 0000000213e69000 CR4: 00000000000006e0 [61666.786253] Call Trace: [61666.786253] __btrfs_drop_extents+0x5e3/0xaad [btrfs] [61666.786253] ? time_hardirqs_on+0x9/0x14 [61666.786253] btrfs_log_changed_extents+0x294/0x4e0 [btrfs] [61666.786253] ? release_extent_buffer+0x38/0xb4 [btrfs] [61666.786253] btrfs_log_inode+0xb6e/0xcdc [btrfs] [61666.786253] ? lock_acquire+0x131/0x1c5 [61666.786253] ? btrfs_log_inode_parent+0xee/0x659 [btrfs] [61666.786253] ? arch_local_irq_save+0x9/0xc [61666.786253] ? btrfs_log_inode_parent+0x1f5/0x659 [btrfs] [61666.786253] btrfs_log_inode_parent+0x223/0x659 [btrfs] [61666.786253] ? arch_local_irq_save+0x9/0xc [61666.786253] ? lockref_get_not_zero+0x2c/0x34 [61666.786253] ? rcu_read_unlock+0x3e/0x5d [61666.786253] btrfs_log_dentry_safe+0x60/0x7b [btrfs] [61666.786253] btrfs_sync_file+0x317/0x42c [btrfs] [61666.786253] vfs_fsync_range+0x8c/0x9e [61666.786253] SyS_msync+0x13c/0x1c9 [61666.786253] entry_SYSCALL_64_fastpath+0x18/0xad A sample of a corrupt log tree leaf with overlapping extents I got from running btrfs/072: item 14 key (295 108 200704) itemoff 2599 itemsize 53 extent data disk bytenr 0 nr 0 extent data offset 0 nr 458752 ram 458752 item 15 key (295 108 659456) itemoff 2546 itemsize 53 extent data disk bytenr 4343541760 nr 770048 extent data offset 606208 nr 163840 ram 770048 item 16 key (295 108 663552) itemoff 2493 itemsize 53 extent data disk bytenr 4343541760 nr 770048 extent data offset 610304 nr 155648 ram 770048 item 17 key (295 108 819200) itemoff 2440 itemsize 53 extent data disk bytenr 4334788608 nr 4096 extent data offset 0 nr 4096 ram 4096 The file extent item at offset 659456 (item 15) ends at offset 823296 (659456 + 163840) while the next file extent item (item 16) starts at offset 663552. Another different problem that the race can trigger is a failure in the assertions at tree-log.c:copy_items(), which expect that the first file extent item key we found before releasing the path exists after we have released path and that the last key we found before releasing the path also exists after releasing the path: $ cat -n fs/btrfs/tree-log.c 4080 if (need_find_last_extent) { 4081 /* btrfs_prev_leaf could return 1 without releasing the path */ 4082 btrfs_release_path(src_path); 4083 ret = btrfs_search_slot(NULL, inode->root, &first_key, 4084 src_path, 0, 0); 4085 if (ret < 0) 4086 return ret; 4087 ASSERT(ret == 0); (...) 4103 if (i >= btrfs_header_nritems(src_path->nodes[0])) { 4104 ret = btrfs_next_leaf(inode->root, src_path); 4105 if (ret < 0) 4106 return ret; 4107 ASSERT(ret == 0); 4108 src = src_path->nodes[0]; 4109 i = 0; 4110 need_find_last_extent = true; 4111 } (...) The second assertion implicitly expects that the last key before the path release still exists, because the surrounding while loop only stops after we have found that key. When this assertion fails it produces a stack like this: [139590.037075] assertion failed: ret == 0, file: fs/btrfs/tree-log.c, line: 4107 [139590.037406] ------------[ cut here ]------------ [139590.037707] kernel BUG at fs/btrfs/ctree.h:3546! [139590.038034] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI [139590.038340] CPU: 1 PID: 31841 Comm: fsstress Tainted: G W 5.0.0-btrfs-next-46 #1 (...) [139590.039354] RIP: 0010:assfail.constprop.24+0x18/0x1a [btrfs] (...) [139590.040397] RSP: 0018:ffffa27f48f2b9b0 EFLAGS: 00010282 [139590.040730] RAX: 0000000000000041 RBX: ffff897c635d92c8 RCX: 0000000000000000 [139590.041105] RDX: 0000000000000000 RSI: ffff897d36a96868 RDI: ffff897d36a96868 [139590.041470] RBP: ffff897d1b9a0708 R08: 0000000000000000 R09: 0000000000000000 [139590.041815] R10: 0000000000000008 R11: 0000000000000000 R12: 0000000000000013 [139590.042159] R13: 0000000000000227 R14: ffff897cffcbba88 R15: 0000000000000001 [139590.042501] FS: 00007f2efc8dee80(0000) GS:ffff897d36a80000(0000) knlGS:0000000000000000 [139590.042847] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [139590.043199] CR2: 00007f8c064935e0 CR3: 0000000232252002 CR4: 00000000003606e0 [139590.043547] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [139590.043899] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [139590.044250] Call Trace: [139590.044631] copy_items+0xa3f/0x1000 [btrfs] [139590.045009] ? generic_bin_search.constprop.32+0x61/0x200 [btrfs] [139590.045396] btrfs_log_inode+0x7b3/0xd70 [btrfs] [139590.045773] btrfs_log_inode_parent+0x2b3/0xce0 [btrfs] [139590.046143] ? do_raw_spin_unlock+0x49/0xc0 [139590.046510] btrfs_log_dentry_safe+0x4a/0x70 [btrfs] [139590.046872] btrfs_sync_file+0x3b6/0x440 [btrfs] [139590.047243] btrfs_file_write_iter+0x45b/0x5c0 [btrfs] [139590.047592] __vfs_write+0x129/0x1c0 [139590.047932] vfs_write+0xc2/0x1b0 [139590.048270] ksys_write+0x55/0xc0 [139590.048608] do_syscall_64+0x60/0x1b0 [139590.048946] entry_SYSCALL_64_after_hwframe+0x49/0xbe [139590.049287] RIP: 0033:0x7f2efc4be190 (...) [139590.050342] RSP: 002b:00007ffe743243a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [139590.050701] RAX: ffffffffffffffda RBX: 0000000000008d58 RCX: 00007f2efc4be190 [139590.051067] RDX: 0000000000008d58 RSI: 00005567eca0f370 RDI: 0000000000000003 [139590.051459] RBP: 0000000000000024 R08: 0000000000000003 R09: 0000000000008d60 [139590.051863] R10: 0000000000000078 R11: 0000000000000246 R12: 0000000000000003 [139590.052252] R13: 00000000003d3507 R14: 00005567eca0f370 R15: 0000000000000000 (...) [139590.055128] ---[ end trace 193f35d0215cdeeb ]--- So fix this race between a full ranged fsync and writeback of adjacent ranges by flushing all delalloc and waiting for all ordered extents to complete before logging the inode. This is the simplest way to solve the problem because currently the full fsync path does not deal with ranges at all (it assumes a full range from 0 to LLONG_MAX) and it always needs to look at adjacent ranges for hole detection. For use cases of ranged fsyncs this can make a few fsyncs slower but on the other hand it can make some following fsyncs to other ranges do less work or no need to do anything at all. A full fsync is rare anyway and happens only once after loading/creating an inode and once after less common operations such as a shrinking truncate. This is an issue that exists for a long time, and was often triggered by generic/127, because it does mmap'ed writes and msync (which triggers a ranged fsync). Adding support for the tree checker to detect overlapping extents (next patch in the series) and trigger a WARN() when such cases are found, and then calling btrfs_check_leaf_full() at the end of btrfs_insert_file_extent() made the issue much easier to detect. Running btrfs/072 with that change to the tree checker and making fsstress open files always with O_SYNC made it much easier to trigger the issue (as triggering it with generic/127 is very rare). CC: stable@vger.kernel.org # 3.16+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31Btrfs: do not abort transaction at btrfs_update_root() after failure to COW pathFilipe Manana
commit 72bd2323ec87722c115a5906bc6a1b31d11e8f54 upstream. Currently when we fail to COW a path at btrfs_update_root() we end up always aborting the transaction. However all the current callers of btrfs_update_root() are able to deal with errors returned from it, many do end up aborting the transaction themselves (directly or not, such as the transaction commit path), other BUG_ON() or just gracefully cancel whatever they were doing. When syncing the fsync log, we call btrfs_update_root() through tree-log.c:update_log_root(), and if it returns an -ENOSPC error, the log sync code does not abort the transaction, instead it gracefully handles the error and returns -EAGAIN to the fsync handler, so that it falls back to a transaction commit. Any other error different from -ENOSPC, makes the log sync code abort the transaction. So remove the transaction abort from btrfs_update_log() when we fail to COW a path to update the root item, so that if an -ENOSPC failure happens we avoid aborting the current transaction and have a chance of the fsync succeeding after falling back to a transaction commit. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203413 Fixes: 79787eaab46121 ("btrfs: replace many BUG_ONs with proper error handling") Cc: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25btrfs: Honour FITRIM range constraints during free space trimNikolay Borisov
commit c2d1b3aae33605a61cbab445d8ae1c708ccd2698 upstream. Up until now trimming the freespace was done irrespective of what the arguments of the FITRIM ioctl were. For example fstrim's -o/-l arguments will be entirely ignored. Fix it by correctly handling those paramter. This requires breaking if the found freespace extent is after the end of the passed range as well as completing trim after trimming fstrim_range::len bytes. Fixes: 499f377f49f0 ("btrfs: iterate over unused chunk space in FITRIM") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21Btrfs: do not start a transaction at iterate_extent_inodes()Filipe Manana
commit bfc61c36260ca990937539cd648ede3cd749bc10 upstream. When finding out which inodes have references on a particular extent, done by backref.c:iterate_extent_inodes(), from the BTRFS_IOC_LOGICAL_INO (both v1 and v2) ioctl and from scrub we use the transaction join API to grab a reference on the currently running transaction, since in order to give accurate results we need to inspect the delayed references of the currently running transaction. However, if there is currently no running transaction, the join operation will create a new transaction. This is inefficient as the transaction will eventually be committed, doing unnecessary IO and introducing a potential point of failure that will lead to a transaction abort due to -ENOSPC, as recently reported [1]. That's because the join, creates the transaction but does not reserve any space, so when attempting to update the root item of the root passed to btrfs_join_transaction(), during the transaction commit, we can end up failling with -ENOSPC. Users of a join operation are supposed to actually do some filesystem changes and reserve space by some means, which is not the case of iterate_extent_inodes(), it is a read-only operation for all contextes from which it is called. The reported [1] -ENOSPC failure stack trace is the following: heisenberg kernel: ------------[ cut here ]------------ heisenberg kernel: BTRFS: Transaction aborted (error -28) heisenberg kernel: WARNING: CPU: 0 PID: 7137 at fs/btrfs/root-tree.c:136 btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: CPU: 0 PID: 7137 Comm: btrfs-transacti Not tainted 4.19.0-4-amd64 #1 Debian 4.19.28-2 heisenberg kernel: Hardware name: FUJITSU LIFEBOOK U757/FJNB2A5, BIOS Version 1.21 03/19/2018 heisenberg kernel: RIP: 0010:btrfs_update_root+0x22b/0x320 [btrfs] (...) heisenberg kernel: RSP: 0018:ffffb5448828bd40 EFLAGS: 00010286 heisenberg kernel: RAX: 0000000000000000 RBX: ffff8ed56bccef50 RCX: 0000000000000006 heisenberg kernel: RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8ed6bda166a0 heisenberg kernel: RBP: 00000000ffffffe4 R08: 00000000000003df R09: 0000000000000007 heisenberg kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ed63396a078 heisenberg kernel: R13: ffff8ed092d7c800 R14: ffff8ed64f5db028 R15: ffff8ed6bd03d068 heisenberg kernel: FS: 0000000000000000(0000) GS:ffff8ed6bda00000(0000) knlGS:0000000000000000 heisenberg kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 heisenberg kernel: CR2: 00007f46f75f8000 CR3: 0000000310a0a002 CR4: 00000000003606f0 heisenberg kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 heisenberg kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 heisenberg kernel: Call Trace: heisenberg kernel: commit_fs_roots+0x166/0x1d0 [btrfs] heisenberg kernel: ? _cond_resched+0x15/0x30 heisenberg kernel: ? btrfs_run_delayed_refs+0xac/0x180 [btrfs] heisenberg kernel: btrfs_commit_transaction+0x2bd/0x870 [btrfs] heisenberg kernel: ? start_transaction+0x9d/0x3f0 [btrfs] heisenberg kernel: transaction_kthread+0x147/0x180 [btrfs] heisenberg kernel: ? btrfs_cleanup_transaction+0x530/0x530 [btrfs] heisenberg kernel: kthread+0x112/0x130 heisenberg kernel: ? kthread_bind+0x30/0x30 heisenberg kernel: ret_from_fork+0x35/0x40 heisenberg kernel: ---[ end trace 05de912e30e012d9 ]--- So fix that by using the attach API, which does not create a transaction when there is currently no running transaction. [1] https://lore.kernel.org/linux-btrfs/b2a668d7124f1d3e410367f587926f622b3f03a4.camel@scientia.net/ Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-17Btrfs: do not allow trimming when a fs is mounted with the nologreplay optionFilipe Manana
commit f35f06c35560a86e841631f0243b83a984dc11a9 upstream. Whan a filesystem is mounted with the nologreplay mount option, which requires it to be mounted in RO mode as well, we can not allow discard on free space inside block groups, because log trees refer to extents that are not pinned in a block group's free space cache (pinning the extents is precisely the first phase of replaying a log tree). So do not allow the fitrim ioctl to do anything when the filesystem is mounted with the nologreplay option, because later it can be mounted RW without that option, which causes log replay to happen and result in either a failure to replay the log trees (leading to a mount failure), a crash or some silent corruption. Reported-by: Darrick J. Wong <darrick.wong@oracle.com> Fixes: 96da09192cda ("btrfs: Introduce new mount option to disable tree log replay") CC: stable@vger.kernel.org # 4.9+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03btrfs: raid56: properly unmap parity page in finish_parity_scrub()Andrea Righi
commit 3897b6f0a859288c22fb793fad11ec2327e60fcd upstream. Parity page is incorrectly unmapped in finish_parity_scrub(), triggering a reference counter bug on i386, i.e.: [ 157.662401] kernel BUG at mm/highmem.c:349! [ 157.666725] invalid opcode: 0000 [#1] SMP PTI The reason is that kunmap(p_page) was completely left out, so we never did an unmap for the p_page and the loop unmapping the rbio page was iterating over the wrong number of stripes: unmapping should be done with nr_data instead of rbio->real_stripes. Test case to reproduce the bug: - create a raid5 btrfs filesystem: # mkfs.btrfs -m raid5 -d raid5 /dev/sdb /dev/sdc /dev/sdd /dev/sde - mount it: # mount /dev/sdb /mnt - run btrfs scrub in a loop: # while :; do btrfs scrub start -BR /mnt; done BugLink: https://bugs.launchpad.net/bugs/1812845 Fixes: 5a6ac9eacb49 ("Btrfs, raid56: support parity scrub on raid56") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03btrfs: remove WARN_ON in log_dir_itemsJosef Bacik
commit 2cc8334270e281815c3850c3adea363c51f21e0d upstream. When Filipe added the recursive directory logging stuff in 2f2ff0ee5e430 ("Btrfs: fix metadata inconsistencies after directory fsync") he specifically didn't take the directory i_mutex for the children directories that we need to log because of lockdep. This is generally fine, but can lead to this WARN_ON() tripping if we happen to run delayed deletion's in between our first search and our second search of dir_item/dir_indexes for this directory. We expect this to happen, so the WARN_ON() isn't necessary. Drop the WARN_ON() and add a comment so we know why this case can happen. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23Btrfs: fix corruption reading shared and compressed extents after hole punchingFilipe Manana
commit 8e928218780e2f1cf2f5891c7575e8f0b284fcce upstream. In the past we had data corruption when reading compressed extents that are shared within the same file and they are consecutive, this got fixed by commit 005efedf2c7d0 ("Btrfs: fix read corruption of compressed and shared extents") and by commit 808f80b46790f ("Btrfs: update fix for read corruption of compressed and shared extents"). However there was a case that was missing in those fixes, which is when the shared and compressed extents are referenced with a non-zero offset. The following shell script creates a reproducer for this issue: #!/bin/bash mkfs.btrfs -f /dev/sdc &> /dev/null mount -o compress /dev/sdc /mnt/sdc # Create a file with 3 consecutive compressed extents, each has an # uncompressed size of 128Kb and a compressed size of 4Kb. for ((i = 1; i <= 3; i++)); do head -c 4096 /dev/zero for ((j = 1; j <= 31; j++)); do head -c 4096 /dev/zero | tr '\0' "\377" done done > /mnt/sdc/foobar sync echo "Digest after file creation: $(md5sum /mnt/sdc/foobar)" # Clone the first extent into offsets 128K and 256K. xfs_io -c "reflink /mnt/sdc/foobar 0 128K 128K" /mnt/sdc/foobar xfs_io -c "reflink /mnt/sdc/foobar 0 256K 128K" /mnt/sdc/foobar sync echo "Digest after cloning: $(md5sum /mnt/sdc/foobar)" # Punch holes into the regions that are already full of zeroes. xfs_io -c "fpunch 0 4K" /mnt/sdc/foobar xfs_io -c "fpunch 128K 4K" /mnt/sdc/foobar xfs_io -c "fpunch 256K 4K" /mnt/sdc/foobar sync echo "Digest after hole punching: $(md5sum /mnt/sdc/foobar)" echo "Dropping page cache..." sysctl -q vm.drop_caches=1 echo "Digest after hole punching: $(md5sum /mnt/sdc/foobar)" umount /dev/sdc When running the script we get the following output: Digest after file creation: 5a0888d80d7ab1fd31c229f83a3bbcc8 /mnt/sdc/foobar linked 131072/131072 bytes at offset 131072 128 KiB, 1 ops; 0.0033 sec (36.960 MiB/sec and 295.6830 ops/sec) linked 131072/131072 bytes at offset 262144 128 KiB, 1 ops; 0.0015 sec (78.567 MiB/sec and 628.5355 ops/sec) Digest after cloning: 5a0888d80d7ab1fd31c229f83a3bbcc8 /mnt/sdc/foobar Digest after hole punching: 5a0888d80d7ab1fd31c229f83a3bbcc8 /mnt/sdc/foobar Dropping page cache... Digest after hole punching: fba694ae8664ed0c2e9ff8937e7f1484 /mnt/sdc/foobar This happens because after reading all the pages of the extent in the range from 128K to 256K for example, we read the hole at offset 256K and then when reading the page at offset 260K we don't submit the existing bio, which is responsible for filling all the page in the range 128K to 256K only, therefore adding the pages from range 260K to 384K to the existing bio and submitting it after iterating over the entire range. Once the bio completes, the uncompressed data fills only the pages in the range 128K to 256K because there's no more data read from disk, leaving the pages in the range 260K to 384K unfilled. It is just a slightly different variant of what was solved by commit 005efedf2c7d0 ("Btrfs: fix read corruption of compressed and shared extents"). Fix this by forcing a bio submit, during readpages(), whenever we find a compressed extent map for a page that is different from the extent map for the previous page or has a different starting offset (in case it's the same compressed extent), instead of the extent map's original start offset. A test case for fstests follows soon. Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Fixes: 808f80b46790f ("Btrfs: update fix for read corruption of compressed and shared extents") Fixes: 005efedf2c7d0 ("Btrfs: fix read corruption of compressed and shared extents") Cc: stable@vger.kernel.org # 4.3+ Tested-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23btrfs: ensure that a DUP or RAID1 block group has exactly two stripesJohannes Thumshirn
commit 349ae63f40638a28c6fce52e8447c2d14b84cc0c upstream. We recently had a customer issue with a corrupted filesystem. When trying to mount this image btrfs panicked with a division by zero in calc_stripe_length(). The corrupt chunk had a 'num_stripes' value of 1. calc_stripe_length() takes this value and divides it by the number of copies the RAID profile is expected to have to calculate the amount of data stripes. As a DUP profile is expected to have 2 copies this division resulted in 1/2 = 0. Later then the 'data_stripes' variable is used as a divisor in the stripe length calculation which results in a division by 0 and thus a kernel panic. When encountering a filesystem with a DUP block group and a 'num_stripes' value unequal to 2, refuse mounting as the image is corrupted and will lead to unexpected behaviour. Code inspection showed a RAID1 block group has the same issues. Fixes: e06cd3dd7cea ("Btrfs: add validadtion checks for chunk loading") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-23btrfs: Remove false alert when fiemap range is smaller than on-disk extentQu Wenruo
commit 848c23b78fafdcd3270b06a30737f8dbd70c347f upstream. Commit 4751832da990 ("btrfs: fiemap: Cache and merge fiemap extent before submit it to user") introduced a warning to catch unemitted cached fiemap extent. However such warning doesn't take the following case into consideration: 0 4K 8K |<---- fiemap range --->| |<----------- On-disk extent ------------------>| In this case, the whole 0~8K is cached, and since it's larger than fiemap range, it break the fiemap extent emit loop. This leaves the fiemap extent cached but not emitted, and caught by the final fiemap extent sanity check, causing kernel warning. This patch removes the kernel warning and renames the sanity check to emit_last_fiemap_cache() since it's possible and valid to have cached fiemap extent. Reported-by: David Sterba <dsterba@suse.cz> Reported-by: Adam Borowski <kilobyte@angband.pl> Fixes: 4751832da990 ("btrfs: fiemap: Cache and merge fiemap extent ...") Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31btrfs: dev-replace: go back to suspended state if target device is missingAnand Jain
commit 0d228ece59a35a9b9e8ff0d40653234a6d90f61e upstream. At the time of forced unmount we place the running replace to BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state, so when the system comes back and expect the target device is missing. Then let the replace state continue to be in BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state instead of BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED as there isn't any matching scrub running as part of replace. Fixes: e93c89c1aaaa ("Btrfs: add new sources for device replace code") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31btrfs: fix error handling in btrfs_dev_replace_startJeff Mahoney
commit 5c06147128fbbdf7a84232c5f0d808f53153defe upstream. When we fail to start a transaction in btrfs_dev_replace_start, we leave dev_replace->replace_start set to STARTED but clear ->srcdev and ->tgtdev. Later, that can result in an Oops in btrfs_dev_replace_progress when having state set to STARTED or SUSPENDED implies that ->srcdev is valid. Also fix error handling when the state is already STARTED or SUSPENDED while starting. That, too, will clear ->srcdev and ->tgtdev even though it doesn't own them. This should be an impossible case to hit since we should be protected by the BTRFS_FS_EXCL_OP bit being set. Let's add an ASSERT there while we're at it. Fixes: e93c89c1aaaaa (Btrfs: add new sources for device replace code) CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-23btrfs: wait on ordered extents on abort cleanupJosef Bacik
commit 74d5d229b1bf60f93bff244b2dfc0eb21ec32a07 upstream. If we flip read-only before we initiate writeback on all dirty pages for ordered extents we've created then we'll have ordered extents left over on umount, which results in all sorts of bad things happening. Fix this by making sure we wait on ordered extents if we have to do the aborted transaction cleanup stuff. generic/475 can produce this warning: [ 8531.177332] WARNING: CPU: 2 PID: 11997 at fs/btrfs/disk-io.c:3856 btrfs_free_fs_root+0x95/0xa0 [btrfs] [ 8531.183282] CPU: 2 PID: 11997 Comm: umount Tainted: G W 5.0.0-rc1-default+ #394 [ 8531.185164] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014 [ 8531.187851] RIP: 0010:btrfs_free_fs_root+0x95/0xa0 [btrfs] [ 8531.193082] RSP: 0018:ffffb1ab86163d98 EFLAGS: 00010286 [ 8531.194198] RAX: ffff9f3449494d18 RBX: ffff9f34a2695000 RCX:0000000000000000 [ 8531.195629] RDX: 0000000000000002 RSI: 0000000000000001 RDI:0000000000000000 [ 8531.197315] RBP: ffff9f344e930000 R08: 0000000000000001 R09:0000000000000000 [ 8531.199095] R10: 0000000000000000 R11: ffff9f34494d4ff8 R12:ffffb1ab86163dc0 [ 8531.200870] R13: ffff9f344e9300b0 R14: ffffb1ab86163db8 R15:0000000000000000 [ 8531.202707] FS: 00007fc68e949fc0(0000) GS:ffff9f34bd800000(0000)knlGS:0000000000000000 [ 8531.204851] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8531.205942] CR2: 00007ffde8114dd8 CR3: 000000002dfbd000 CR4:00000000000006e0 [ 8531.207516] Call Trace: [ 8531.208175] btrfs_free_fs_roots+0xdb/0x170 [btrfs] [ 8531.210209] ? wait_for_completion+0x5b/0x190 [ 8531.211303] close_ctree+0x157/0x350 [btrfs] [ 8531.212412] generic_shutdown_super+0x64/0x100 [ 8531.213485] kill_anon_super+0x14/0x30 [ 8531.214430] btrfs_kill_super+0x12/0xa0 [btrfs] [ 8531.215539] deactivate_locked_super+0x29/0x60 [ 8531.216633] cleanup_mnt+0x3b/0x70 [ 8531.217497] task_work_run+0x98/0xc0 [ 8531.218397] exit_to_usermode_loop+0x83/0x90 [ 8531.219324] do_syscall_64+0x15b/0x180 [ 8531.220192] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 8531.221286] RIP: 0033:0x7fc68e5e4d07 [ 8531.225621] RSP: 002b:00007ffde8116608 EFLAGS: 00000246 ORIG_RAX:00000000000000a6 [ 8531.227512] RAX: 0000000000000000 RBX: 00005580c2175970 RCX:00007fc68e5e4d07 [ 8531.229098] RDX: 0000000000000001 RSI: 0000000000000000 RDI:00005580c2175b80 [ 8531.230730] RBP: 0000000000000000 R08: 00005580c2175ba0 R09:00007ffde8114e80 [ 8531.232269] R10: 0000000000000000 R11: 0000000000000246 R12:00005580c2175b80 [ 8531.233839] R13: 00007fc68eac61c4 R14: 00005580c2175a68 R15:0000000000000000 Leaving a tree in the rb-tree: 3853 void btrfs_free_fs_root(struct btrfs_root *root) 3854 { 3855 iput(root->ino_cache_inode); 3856 WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree)); CC: stable@vger.kernel.org Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> [ add stacktrace ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17Btrfs: send, fix infinite loop due to directory rename dependenciesRobbie Ko
[ Upstream commit a4390aee72713d9e73f1132bcdeb17d72fbbf974 ] When doing an incremental send, due to the need of delaying directory move (rename) operations we can end up in infinite loop at apply_children_dir_moves(). An example scenario that triggers this problem is described below, where directory names correspond to the numbers of their respective inodes. Parent snapshot: . |--- 261/ |--- 271/ |--- 266/ |--- 259/ |--- 260/ | |--- 267 | |--- 264/ | |--- 258/ | |--- 257/ | |--- 265/ |--- 268/ |--- 269/ | |--- 262/ | |--- 270/ |--- 272/ | |--- 263/ | |--- 275/ | |--- 274/ |--- 273/ Send snapshot: . |-- 275/ |-- 274/ |-- 273/ |-- 262/ |-- 269/ |-- 258/ |-- 271/ |-- 268/ |-- 267/ |-- 270/ |-- 259/ | |-- 265/ | |-- 272/ |-- 257/ |-- 260/ |-- 264/ |-- 263/ |-- 261/ |-- 266/ When processing inode 257 we delay its move (rename) operation because its new parent in the send snapshot, inode 272, was not yet processed. Then when processing inode 272, we delay the move operation for that inode because inode 274 is its ancestor in the send snapshot. Finally we delay the move operation for inode 274 when processing it because inode 275 is its new parent in the send snapshot and was not yet moved. When finishing processing inode 275, we start to do the move operations that were previously delayed (at apply_children_dir_moves()), resulting in the following iterations: 1) We issue the move operation for inode 274; 2) Because inode 262 depended on the move operation of inode 274 (it was delayed because 274 is its ancestor in the send snapshot), we issue the move operation for inode 262; 3) We issue the move operation for inode 272, because it was delayed by inode 274 too (ancestor of 272 in the send snapshot); 4) We issue the move operation for inode 269 (it was delayed by 262); 5) We issue the move operation for inode 257 (it was delayed by 272); 6) We issue the move operation for inode 260 (it was delayed by 272); 7) We issue the move operation for inode 258 (it was delayed by 269); 8) We issue the move operation for inode 264 (it was delayed by 257); 9) We issue the move operation for inode 271 (it was delayed by 258); 10) We issue the move operation for inode 263 (it was delayed by 264); 11) We issue the move operation for inode 268 (it was delayed by 271); 12) We verify if we can issue the move operation for inode 270 (it was delayed by 271). We detect a path loop in the current state, because inode 267 needs to be moved first before we can issue the move operation for inode 270. So we delay again the move operation for inode 270, this time we will attempt to do it after inode 267 is moved; 13) We issue the move operation for inode 261 (it was delayed by 263); 14) We verify if we can issue the move operation for inode 266 (it was delayed by 263). We detect a path loop in the current state, because inode 270 needs to be moved first before we can issue the move operation for inode 266. So we delay again the move operation for inode 266, this time we will attempt to do it after inode 270 is moved (its move operation was delayed in step 12); 15) We issue the move operation for inode 267 (it was delayed by 268); 16) We verify if we can issue the move operation for inode 266 (it was delayed by 270). We detect a path loop in the current state, because inode 270 needs to be moved first before we can issue the move operation for inode 266. So we delay again the move operation for inode 266, this time we will attempt to do it after inode 270 is moved (its move operation was delayed in step 12). So here we added again the same delayed move operation that we added in step 14; 17) We attempt again to see if we can issue the move operation for inode 266, and as in step 16, we realize we can not due to a path loop in the current state due to a dependency on inode 270. Again we delay inode's 266 rename to happen after inode's 270 move operation, adding the same dependency to the empty stack that we did in steps 14 and 16. The next iteration will pick the same move dependency on the stack (the only entry) and realize again there is still a path loop and then again the same dependency to the stack, over and over, resulting in an infinite loop. So fix this by preventing adding the same move dependency entries to the stack by removing each pending move record from the red black tree of pending moves. This way the next call to get_pending_dir_moves() will not return anything for the current parent inode. A test case for fstests, with this reproducer, follows soon. Signed-off-by: Robbie Ko <robbieko@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> [Wrote changelog with example and more clear explanation] Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-08btrfs: tree-checker: Fix misleading group system informationShaokun Zhang
commit 761333f2f50ccc887aa9957ae829300262c0d15b upstream. block_group_err shows the group system as a decimal value with a '0x' prefix, which is somewhat misleading. Fix it to print hexadecimal, as was intended. Fixes: fce466eab7ac6 ("btrfs: tree-checker: Verify block_group_item") Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-checker: Check level for leaves and nodesQu Wenruo
commit f556faa46eb4e96d0d0772e74ecf66781e132f72 upstream. Although we have tree level check at tree read runtime, it's completely based on its parent level. We still need to do accurate level check to avoid invalid tree blocks sneak into kernel space. The check itself is simple, for leaf its level should always be 0. For nodes its level should be in range [1, BTRFS_MAX_LEVEL - 1]. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: - Pass root instead of fs_info to generic_err() - Adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Check that each block group has corresponding chunk at mount timeQu Wenruo
commit 514c7dca85a0bf40be984dab0b477403a6db901f upstream. A crafted btrfs image with incorrect chunk<->block group mapping will trigger a lot of unexpected things as the mapping is essential. Although the problem can be caught by block group item checker added in "btrfs: tree-checker: Verify block_group_item", it's still not sufficient. A sufficiently valid block group item can pass the check added by the mentioned patch but could fail to match the existing chunk. This patch will add extra block group -> chunk mapping check, to ensure we have a completely matching (start, len, flags) chunk for each block group at mount time. Here we reuse the original helper find_first_block_group(), which is already doing the basic bg -> chunk checks, adding further checks of the start/len and type flags. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199837 Reported-by: Xu Wen <wen.xu@gatech.edu> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: Use root->fs_info instead of fs_info] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-checker: Detect invalid and empty essential treesQu Wenruo
commit ba480dd4db9f1798541eb2d1c423fc95feee8d36 upstream. A crafted image has empty root tree block, which will later cause NULL pointer dereference. The following trees should never be empty: 1) Tree root Must contain at least root items for extent tree, device tree and fs tree 2) Chunk tree Or we can't even bootstrap as it contains the mapping. 3) Fs tree At least inode item for top level inode (.). 4) Device tree Dev extents for chunks 5) Extent tree Must have corresponding extent for each chunk. If any of them is empty, we are sure the fs is corrupted and no need to mount it. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199847 Reported-by: Xu Wen <wen.xu@gatech.edu> Signed-off-by: Qu Wenruo <wqu@suse.com> Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: Pass root instead of fs_info to generic_err()] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-checker: Verify block_group_itemQu Wenruo
commit fce466eab7ac6baa9d2dcd88abcf945be3d4a089 upstream. A crafted image with invalid block group items could make free space cache code to cause panic. We could detect such invalid block group item by checking: 1) Item size Known fixed value. 2) Block group size (key.offset) We have an upper limit on block group item (10G) 3) Chunk objectid Known fixed value. 4) Type Only 4 valid type values, DATA, METADATA, SYSTEM and DATA|METADATA. No more than 1 bit set for profile type. 5) Used space No more than the block group size. This should allow btrfs to detect and refuse to mount the crafted image. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199849 Reported-by: Xu Wen <wen.xu@gatech.edu> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: - In check_leaf_item(), pass root->fs_info to check_block_group_item() - Adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-check: reduce stack consumption in check_dir_itemDavid Sterba
commit e2683fc9d219430f5b78889b50cde7f40efeba7b upstream. I've noticed that the updated item checker stack consumption increased dramatically in 542f5385e20cf97447 ("btrfs: tree-checker: Add checker for dir item") tree-checker.c:check_leaf +552 (176 -> 728) The array is 255 bytes long, dynamic allocation would slow down the sanity checks so it's more reasonable to keep it on-stack. Moving the variable to the scope of use reduces the stack usage again tree-checker.c:check_leaf -264 (728 -> 464) Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-checker: use %zu format string for size_tArnd Bergmann
commit 7cfad65297bfe0aa2996cd72d21c898aa84436d9 upstream. The return value of sizeof() is of type size_t, so we must print it using the %z format modifier rather than %l to avoid this warning on some architectures: fs/btrfs/tree-checker.c: In function 'check_dir_item': fs/btrfs/tree-checker.c:273:50: error: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'u32' {aka 'unsigned int'} [-Werror=format=] Fixes: 005887f2e3e0 ("btrfs: tree-checker: Add checker for dir item") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-checker: Add checker for dir itemQu Wenruo
commit ad7b0368f33cffe67fecd302028915926e50ef7e upstream. Add checker for dir item, for key types DIR_ITEM, DIR_INDEX and XATTR_ITEM. This checker does comprehensive checks for: 1) dir_item header and its data size Against item boundary and maximum name/xattr length. This part is mostly the same as old verify_dir_item(). 2) dir_type Against maximum file types, and against key type. Since XATTR key should only have FT_XATTR dir item, and normal dir item type should not have XATTR key. The check between key->type and dir_type is newly introduced by this patch. 3) name hash For XATTR and DIR_ITEM key, key->offset is name hash (crc32c). Check the hash of the name against the key to ensure it's correct. The name hash check is only found in btrfs-progs before this patch. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: BTRFS_MAX_XATTR_SIZE() takes a root not an fs_info] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-checker: Fix false panic for sanity testQu Wenruo
commit 69fc6cbbac542c349b3d350d10f6e394c253c81d upstream. [BUG] If we run btrfs with CONFIG_BTRFS_FS_RUN_SANITY_TESTS=y, it will instantly cause kernel panic like: ------ ... assertion failed: 0, file: fs/btrfs/disk-io.c, line: 3853 ... Call Trace: btrfs_mark_buffer_dirty+0x187/0x1f0 [btrfs] setup_items_for_insert+0x385/0x650 [btrfs] __btrfs_drop_extents+0x129a/0x1870 [btrfs] ... ----- [Cause] Btrfs will call btrfs_check_leaf() in btrfs_mark_buffer_dirty() to check if the leaf is valid with CONFIG_BTRFS_FS_RUN_SANITY_TESTS=y. However quite some btrfs_mark_buffer_dirty() callers(*) don't really initialize its item data but only initialize its item pointers, leaving item data uninitialized. This makes tree-checker catch uninitialized data as error, causing such panic. *: These callers include but not limited to setup_items_for_insert() btrfs_split_item() btrfs_expand_item() [Fix] Add a new parameter @check_item_data to btrfs_check_leaf(). With @check_item_data set to false, item data check will be skipped and fallback to old btrfs_check_leaf() behavior. So we can still get early warning if we screw up item pointers, and avoid false panic. Cc: Filipe Manana <fdmanana@gmail.com> Reported-by: Lakshmipathi.G <lakshmipathi.g@gmail.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: tree-checker: Enhance btrfs_check_node outputQu Wenruo
commit bba4f29896c986c4cec17bc0f19f2ce644fceae1 upstream. Use inline function to replace macro since we don't need stringification. (Macro still exists until all callers get updated) And add more info about the error, and replace EIO with EUCLEAN. For nr_items error, report if it's too large or too small, and output the valid value range. For node block pointer, added a new alignment checker. For key order, also output the next key to make the problem more obvious. Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com> [ wording adjustments, unindented long strings ] Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: - Use root->sectorsize instead of root->fs_info->sectorsize - BTRFS_NODEPTRS_PER_BLOCK() takes a root instead of an fs_info] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: struct-funcs, constify readersJeff Mahoney
commit 1cbb1f454e5321e47fc1e6b233066c7ccc979d15 upstream. We have reader helpers for most of the on-disk structures that use an extent_buffer and pointer as offset into the buffer that are read-only. We should mark them as const and, in turn, allow consumers of these interfaces to mark the buffers const as well. No impact on code, but serves as documentation that a buffer is intended not to be modified. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Move leaf and node validation checker to tree-checker.cQu Wenruo
commit 557ea5dd003d371536f6b4e8f7c8209a2b6fd4e3 upstream. It's no doubt the comprehensive tree block checker will become larger, so moving them into their own files is quite reasonable. Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com> [ wording adjustments ] Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: The moved code is slightly different] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Add checker for EXTENT_CSUMQu Wenruo
commit 4b865cab96fe2a30ed512cf667b354bd291b3b0a upstream. EXTENT_CSUM checker is a relatively easy one, only needs to check: 1) Objectid Fixed to BTRFS_EXTENT_CSUM_OBJECTID 2) Key offset alignment Must be aligned to sectorsize 3) Item size alignedment Must be aligned to csum size Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: Use root->sectorsize instead of root->fs_info->sectorsize] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Add sanity check for EXTENT_DATA when reading out leafQu Wenruo
commit 40c3c40947324d9f40bf47830c92c59a9bbadf4a upstream. Add extra checks for item with EXTENT_DATA type. This checks the following thing: 0) Key offset All key offsets must be aligned to sectorsize. Inline extent must have 0 for key offset. 1) Item size Uncompressed inline file extent size must match item size. (Compressed inline file extent has no information about its on-disk size.) Regular/preallocated file extent size must be a fixed value. 2) Every member of regular file extent item Including alignment for bytenr and offset, possible value for compression/encryption/type. 3) Type/compression/encode must be one of the valid values. This should be the most comprehensive and strict check in the context of btrfs_item for EXTENT_DATA. Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ switch to BTRFS_FILE_EXTENT_TYPES, similar to what BTRFS_COMPRESS_TYPES does ] Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: Use root->sectorsize instead of root->fs_info->sectorsize] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Check if item pointer overlaps with the item itselfQu Wenruo
commit 7f43d4affb2a254d421ab20b0cf65ac2569909fb upstream. Function check_leaf() checks if any item pointer points outside of the leaf, but it doesn't check if the pointer overlaps with the item itself. Normally only the last item may be the victim, but adding such check is never a bad idea anyway. Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Refactor check_leaf function for later expansionQu Wenruo
commit c3267bbaa9cae09b62960eafe33ad19196803285 upstream. Current check_leaf() function does a good job checking key order and item offset/size. However it only checks from slot 0 to the last but one slot, this is good but makes later expansion hard. So this refactoring iterates from slot 0 to the last slot. For key comparison, it uses a key with all 0 as initial key, so all valid keys should be larger than that. And for item size/offset checks, it compares current item end with previous item offset. For slot 0, use leaf end as a special case. This makes later item/key offset checks and item size checks easier to be implemented. Also, makes check_leaf() to return -EUCLEAN other than -EIO to indicate error. Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: - BTRFS_LEAF_DATA_SIZE() takes a root rather than an fs_info - Adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Verify that every chunk has corresponding block group at mount timeQu Wenruo
commit 7ef49515fa6727cb4b6f2f5b0ffbc5fc20a9f8c6 upstream. If a crafted image has missing block group items, it could cause unexpected behavior and breaks the assumption of 1:1 chunk<->block group mapping. Although we have the block group -> chunk mapping check, we still need chunk -> block group mapping check. This patch will do extra check to ensure each chunk has its corresponding block group. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199847 Reported-by: Xu Wen <wen.xu@gatech.edu> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: validate type when reading a chunkGu Jinxiang
commit 315409b0098fb2651d86553f0436b70502b29bb2 upstream. Reported in https://bugzilla.kernel.org/show_bug.cgi?id=199839, with an image that has an invalid chunk type but does not return an error. Add chunk type check in btrfs_check_chunk_valid, to detect the wrong type combinations. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199839 Reported-by: Xu Wen <wen.xu@gatech.edu> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com> [bwh: Backported to 4.9: Use root->fs_info instead of fs_info] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08Btrfs: fix use-after-free when dumping free spaceFilipe Manana
commit 9084cb6a24bf5838a665af92ded1af8363f9e563 upstream. We were iterating a block group's free space cache rbtree without locking first the lock that protects it (the free_space_ctl->free_space_offset rbtree is protected by the free_space_ctl->tree_lock spinlock). KASAN reported an use-after-free problem when iterating such a rbtree due to a concurrent rbtree delete: [ 9520.359168] ================================================================== [ 9520.359656] BUG: KASAN: use-after-free in rb_next+0x13/0x90 [ 9520.359949] Read of size 8 at addr ffff8800b7ada500 by task btrfs-transacti/1721 [ 9520.360357] [ 9520.360530] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G L 4.19.0-rc8-nbor #555 [ 9520.360990] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 9520.362682] Call Trace: [ 9520.362887] dump_stack+0xa4/0xf5 [ 9520.363146] print_address_description+0x78/0x280 [ 9520.363412] kasan_report+0x263/0x390 [ 9520.363650] ? rb_next+0x13/0x90 [ 9520.363873] __asan_load8+0x54/0x90 [ 9520.364102] rb_next+0x13/0x90 [ 9520.364380] btrfs_dump_free_space+0x146/0x160 [btrfs] [ 9520.364697] dump_space_info+0x2cd/0x310 [btrfs] [ 9520.364997] btrfs_reserve_extent+0x1ee/0x1f0 [btrfs] [ 9520.365310] __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs] [ 9520.365646] ? btrfs_update_time+0x180/0x180 [btrfs] [ 9520.365923] ? _raw_spin_unlock+0x27/0x40 [ 9520.366204] ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs] [ 9520.366549] btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs] [ 9520.366880] cache_save_setup+0x42e/0x580 [btrfs] [ 9520.367220] ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs] [ 9520.367518] ? lock_downgrade+0x2f0/0x2f0 [ 9520.367799] ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs] [ 9520.368104] ? kasan_check_read+0x11/0x20 [ 9520.368349] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.368638] btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs] [ 9520.368978] ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs] [ 9520.369282] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.369534] ? _raw_spin_unlock+0x27/0x40 [ 9520.369811] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.370137] commit_cowonly_roots+0x4b9/0x610 [btrfs] [ 9520.370560] ? commit_fs_roots+0x350/0x350 [btrfs] [ 9520.370926] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.371285] btrfs_commit_transaction+0x5e5/0x10e0 [btrfs] [ 9520.371612] ? btrfs_apply_pending_changes+0x90/0x90 [btrfs] [ 9520.371943] ? start_transaction+0x168/0x6c0 [btrfs] [ 9520.372257] transaction_kthread+0x21c/0x240 [btrfs] [ 9520.372537] kthread+0x1d2/0x1f0 [ 9520.372793] ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs] [ 9520.373090] ? kthread_park+0xb0/0xb0 [ 9520.373329] ret_from_fork+0x3a/0x50 [ 9520.373567] [ 9520.373738] Allocated by task 1804: [ 9520.373974] kasan_kmalloc+0xff/0x180 [ 9520.374208] kasan_slab_alloc+0x11/0x20 [ 9520.374447] kmem_cache_alloc+0xfc/0x2d0 [ 9520.374731] __btrfs_add_free_space+0x40/0x580 [btrfs] [ 9520.375044] unpin_extent_range+0x4f7/0x7a0 [btrfs] [ 9520.375383] btrfs_finish_extent_commit+0x15f/0x4d0 [btrfs] [ 9520.375707] btrfs_commit_transaction+0xb06/0x10e0 [btrfs] [ 9520.376027] btrfs_alloc_data_chunk_ondemand+0x237/0x5c0 [btrfs] [ 9520.376365] btrfs_check_data_free_space+0x81/0xd0 [btrfs] [ 9520.376689] btrfs_delalloc_reserve_space+0x25/0x80 [btrfs] [ 9520.377018] btrfs_direct_IO+0x42e/0x6d0 [btrfs] [ 9520.377284] generic_file_direct_write+0x11e/0x220 [ 9520.377587] btrfs_file_write_iter+0x472/0xac0 [btrfs] [ 9520.377875] aio_write+0x25c/0x360 [ 9520.378106] io_submit_one+0xaa0/0xdc0 [ 9520.378343] __se_sys_io_submit+0xfa/0x2f0 [ 9520.378589] __x64_sys_io_submit+0x43/0x50 [ 9520.378840] do_syscall_64+0x7d/0x240 [ 9520.379081] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 9520.379387] [ 9520.379557] Freed by task 1802: [ 9520.379782] __kasan_slab_free+0x173/0x260 [ 9520.380028] kasan_slab_free+0xe/0x10 [ 9520.380262] kmem_cache_free+0xc1/0x2c0 [ 9520.380544] btrfs_find_space_for_alloc+0x4cd/0x4e0 [btrfs] [ 9520.380866] find_free_extent+0xa99/0x17e0 [btrfs] [ 9520.381166] btrfs_reserve_extent+0xd5/0x1f0 [btrfs] [ 9520.381474] btrfs_get_blocks_direct+0x60b/0xbd0 [btrfs] [ 9520.381761] __blockdev_direct_IO+0x10ee/0x58a1 [ 9520.382059] btrfs_direct_IO+0x25a/0x6d0 [btrfs] [ 9520.382321] generic_file_direct_write+0x11e/0x220 [ 9520.382623] btrfs_file_write_iter+0x472/0xac0 [btrfs] [ 9520.382904] aio_write+0x25c/0x360 [ 9520.383172] io_submit_one+0xaa0/0xdc0 [ 9520.383416] __se_sys_io_submit+0xfa/0x2f0 [ 9520.383678] __x64_sys_io_submit+0x43/0x50 [ 9520.383927] do_syscall_64+0x7d/0x240 [ 9520.384165] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 9520.384439] [ 9520.384610] The buggy address belongs to the object at ffff8800b7ada500 which belongs to the cache btrfs_free_space of size 72 [ 9520.385175] The buggy address is located 0 bytes inside of 72-byte region [ffff8800b7ada500, ffff8800b7ada548) [ 9520.385691] The buggy address belongs to the page: [ 9520.385957] page:ffffea0002deb680 count:1 mapcount:0 mapping:ffff880108a1d700 index:0x0 compound_mapcount: 0 [ 9520.388030] flags: 0x8100(slab|head) [ 9520.388281] raw: 0000000000008100 ffffea0002deb608 ffffea0002728808 ffff880108a1d700 [ 9520.388722] raw: 0000000000000000 0000000000130013 00000001ffffffff 0000000000000000 [ 9520.389169] page dumped because: kasan: bad access detected [ 9520.389473] [ 9520.389658] Memory state around the buggy address: [ 9520.389943] ffff8800b7ada400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.390368] ffff8800b7ada480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.390796] >ffff8800b7ada500: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc [ 9520.391223] ^ [ 9520.391461] ffff8800b7ada580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.391885] ffff8800b7ada600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.392313] ================================================================== [ 9520.392772] BTRFS critical (device vdc): entry offset 2258497536, bytes 131072, bitmap no [ 9520.393247] BUG: unable to handle kernel NULL pointer dereference at 0000000000000011 [ 9520.393705] PGD 800000010dbab067 P4D 800000010dbab067 PUD 107551067 PMD 0 [ 9520.394059] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 9520.394378] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G B L 4.19.0-rc8-nbor #555 [ 9520.394858] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 9520.395350] RIP: 0010:rb_next+0x3c/0x90 [ 9520.396461] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292 [ 9520.396762] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c [ 9520.397115] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011 [ 9520.397468] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc [ 9520.397821] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000 [ 9520.398188] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000 [ 9520.398555] FS: 0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000 [ 9520.399007] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9520.399335] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0 [ 9520.399679] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 9520.400023] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 9520.400400] Call Trace: [ 9520.400648] btrfs_dump_free_space+0x146/0x160 [btrfs] [ 9520.400974] dump_space_info+0x2cd/0x310 [btrfs] [ 9520.401287] btrfs_reserve_extent+0x1ee/0x1f0 [btrfs] [ 9520.401609] __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs] [ 9520.401952] ? btrfs_update_time+0x180/0x180 [btrfs] [ 9520.402232] ? _raw_spin_unlock+0x27/0x40 [ 9520.402522] ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs] [ 9520.402882] btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs] [ 9520.403261] cache_save_setup+0x42e/0x580 [btrfs] [ 9520.403570] ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs] [ 9520.403871] ? lock_downgrade+0x2f0/0x2f0 [ 9520.404161] ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs] [ 9520.404481] ? kasan_check_read+0x11/0x20 [ 9520.404732] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.405026] btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs] [ 9520.405375] ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs] [ 9520.405694] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.405958] ? _raw_spin_unlock+0x27/0x40 [ 9520.406243] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.406574] commit_cowonly_roots+0x4b9/0x610 [btrfs] [ 9520.406899] ? commit_fs_roots+0x350/0x350 [btrfs] [ 9520.407253] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.407589] btrfs_commit_transaction+0x5e5/0x10e0 [btrfs] [ 9520.407925] ? btrfs_apply_pending_changes+0x90/0x90 [btrfs] [ 9520.408262] ? start_transaction+0x168/0x6c0 [btrfs] [ 9520.408582] transaction_kthread+0x21c/0x240 [btrfs] [ 9520.408870] kthread+0x1d2/0x1f0 [ 9520.409138] ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs] [ 9520.409440] ? kthread_park+0xb0/0xb0 [ 9520.409682] ret_from_fork+0x3a/0x50 [ 9520.410508] Dumping ftrace buffer: [ 9520.410764] (ftrace buffer empty) [ 9520.411007] CR2: 0000000000000011 [ 9520.411297] ---[ end trace 01a0863445cf360a ]--- [ 9520.411568] RIP: 0010:rb_next+0x3c/0x90 [ 9520.412644] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292 [ 9520.412932] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c [ 9520.413274] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011 [ 9520.413616] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc [ 9520.414007] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000 [ 9520.414349] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000 [ 9520.416074] FS: 0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000 [ 9520.416536] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9520.416848] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0 [ 9520.418477] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 9520.418846] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 9520.419204] Kernel panic - not syncing: Fatal exception [ 9520.419666] Dumping ftrace buffer: [ 9520.419930] (ftrace buffer empty) [ 9520.420168] Kernel Offset: disabled [ 9520.420406] ---[ end Kernel panic - not syncing: Fatal exception ]--- Fix this by acquiring the respective lock before iterating the rbtree. Reported-by: Nikolay Borisov <nborisov@suse.com> CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Cc: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08btrfs: Always try all copies when reading extent buffersNikolay Borisov
commit f8397d69daef06d358430d3054662fb597e37c00 upstream. When a metadata read is served the endio routine btree_readpage_end_io_hook is called which eventually runs the tree-checker. If tree-checker fails to validate the read eb then it sets EXTENT_BUFFER_CORRUPT flag. This leads to btree_read_extent_buffer_pages wrongly assuming that all available copies of this extent buffer are wrong and failing prematurely. Fix this modify btree_read_extent_buffer_pages to read all copies of the data. This failure was exhibitted in xfstests btrfs/124 which would spuriously fail its balance operations. The reason was that when balance was run following re-introduction of the missing raid1 disk __btrfs_map_block would map the read request to stripe 0, which corresponded to devid 2 (the disk which is being removed in the test): item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 3553624064) itemoff 15975 itemsize 112 length 1073741824 owner 2 stripe_len 65536 type DATA|RAID1 io_align 65536 io_width 65536 sector_size 4096 num_stripes 2 sub_stripes 1 stripe 0 devid 2 offset 2156920832 dev_uuid 8466c350-ed0c-4c3b-b17d-6379b445d5c8 stripe 1 devid 1 offset 3553624064 dev_uuid 1265d8db-5596-477e-af03-df08eb38d2ca This caused read requests for a checksum item that to be routed to the stale disk which triggered the aforementioned logic involving EXTENT_BUFFER_CORRUPT flag. This then triggered cascading failures of the balance operation. Fixes: a826d6dcb32d ("Btrfs: check items for correctness as we search") CC: stable@vger.kernel.org # 4.4+ Suggested-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05btrfs: release metadata before running delayed refsJosef Bacik
We want to release the unused reservation we have since it refills the delayed refs reserve, which will make everything go smoother when running the delayed refs if we're short on our reservation. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>