summaryrefslogtreecommitdiff
path: root/fs/btrfs
AgeCommit message (Collapse)AuthorFilesLines
43 hoursbtrfs: do not allow relocation of partially dropped subvolumesQu Wenruo1-0/+19
commit 4289b494ac553e74e86fed1c66b2bf9530bc1082 upstream. [BUG] There is an internal report that balance triggered transaction abort, with the following call trace: item 85 key (594509824 169 0) itemoff 12599 itemsize 33 extent refs 1 gen 197740 flags 2 ref#0: tree block backref root 7 item 86 key (594558976 169 0) itemoff 12566 itemsize 33 extent refs 1 gen 197522 flags 2 ref#0: tree block backref root 7 ... BTRFS error (device loop0): extent item not found for insert, bytenr 594526208 num_bytes 16384 parent 449921024 root_objectid 934 owner 1 offset 0 BTRFS error (device loop0): failed to run delayed ref for logical 594526208 num_bytes 16384 type 182 action 1 ref_mod 1: -117 ------------[ cut here ]------------ BTRFS: Transaction aborted (error -117) WARNING: CPU: 1 PID: 6963 at ../fs/btrfs/extent-tree.c:2168 btrfs_run_delayed_refs+0xfa/0x110 [btrfs] And btrfs check doesn't report anything wrong related to the extent tree. [CAUSE] The cause is a little complex, firstly the extent tree indeed doesn't have the backref for 594526208. The extent tree only have the following two backrefs around that bytenr on-disk: item 65 key (594509824 METADATA_ITEM 0) itemoff 13880 itemsize 33 refs 1 gen 197740 flags TREE_BLOCK tree block skinny level 0 (176 0x7) tree block backref root CSUM_TREE item 66 key (594558976 METADATA_ITEM 0) itemoff 13847 itemsize 33 refs 1 gen 197522 flags TREE_BLOCK tree block skinny level 0 (176 0x7) tree block backref root CSUM_TREE But the such missing backref item is not an corruption on disk, as the offending delayed ref belongs to subvolume 934, and that subvolume is being dropped: item 0 key (934 ROOT_ITEM 198229) itemoff 15844 itemsize 439 generation 198229 root_dirid 256 bytenr 10741039104 byte_limit 0 bytes_used 345571328 last_snapshot 198229 flags 0x1000000000001(RDONLY) refs 0 drop_progress key (206324 EXTENT_DATA 2711650304) drop_level 2 level 2 generation_v2 198229 And that offending tree block 594526208 is inside the dropped range of that subvolume. That explains why there is no backref item for that bytenr and why btrfs check is not reporting anything wrong. But this also shows another problem, as btrfs will do all the orphan subvolume cleanup at a read-write mount. So half-dropped subvolume should not exist after an RW mount, and balance itself is also exclusive to subvolume cleanup, meaning we shouldn't hit a subvolume half-dropped during relocation. The root cause is, there is no orphan item for this subvolume. In fact there are 5 subvolumes from around 2021 that have the same problem. It looks like the original report has some older kernels running, and caused those zombie subvolumes. Thankfully upstream commit 8d488a8c7ba2 ("btrfs: fix subvolume/snapshot deletion not triggered on mount") has long fixed the bug. [ENHANCEMENT] For repairing such old fs, btrfs-progs will be enhanced. Considering how delayed the problem will show up (at run delayed ref time) and at that time we have to abort transaction already, it is too late. Instead here we reject any half-dropped subvolume for reloc tree at the earliest time, preventing confusion and extra time wasted on debugging similar bugs. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
43 hoursbtrfs: fix iteration bug in __qgroup_excl_accounting()Boris Burkov1-2/+1
commit 7b632596188e1973c6b3ac1c9f8252f735e1039f upstream. __qgroup_excl_accounting() uses the qgroup iterator machinery to update the account of one qgroups usage for all its parent hierarchy, when we either add or remove a relation and have only exclusive usage. However, there is a small bug there: we loop with an extra iteration temporary qgroup called `cur` but never actually refer to that in the body of the loop. As a result, we redundantly account the same usage to the first qgroup in the list. This can be reproduced in the following way: mkfs.btrfs -f -O squota <dev> mount <dev> <mnt> btrfs subvol create <mnt>/sv dd if=/dev/zero of=<mnt>/sv/f bs=1M count=1 sync btrfs qgroup create 1/100 <mnt> btrfs qgroup create 2/200 <mnt> btrfs qgroup assign 1/100 2/200 <mnt> btrfs qgroup assign 0/256 1/100 <mnt> btrfs qgroup show <mnt> and the broken result is (note the 2MiB on 1/100 and 0Mib on 2/100): Qgroupid Referenced Exclusive Path -------- ---------- --------- ---- 0/5 16.00KiB 16.00KiB <toplevel> 0/256 1.02MiB 1.02MiB sv Qgroupid Referenced Exclusive Path -------- ---------- --------- ---- 0/5 16.00KiB 16.00KiB <toplevel> 0/256 1.02MiB 1.02MiB sv 1/100 2.03MiB 2.03MiB 2/100<1 member qgroup> 2/100 0.00B 0.00B <0 member qgroups> With this fix, which simply re-uses `qgroup` as the iteration variable, we see the expected result: Qgroupid Referenced Exclusive Path -------- ---------- --------- ---- 0/5 16.00KiB 16.00KiB <toplevel> 0/256 1.02MiB 1.02MiB sv Qgroupid Referenced Exclusive Path -------- ---------- --------- ---- 0/5 16.00KiB 16.00KiB <toplevel> 0/256 1.02MiB 1.02MiB sv 1/100 1.02MiB 1.02MiB 2/100<1 member qgroup> 2/100 1.02MiB 1.02MiB <0 member qgroups> The existing fstests did not exercise two layer inheritance so this bug was missed. I intend to add that testing there, as well. Fixes: a0bdc04b0732 ("btrfs: qgroup: use qgroup_iterator in __qgroup_excl_accounting()") CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
43 hoursbtrfs: zoned: do not select metadata BG as finish targetNaohiro Aota1-1/+1
commit 3a931e9b39c7ff8066657042f5f00d3b7e6ad315 upstream. We call btrfs_zone_finish_one_bg() to zone finish one block group and make room to activate another block group. Currently, we can choose a metadata block group as a target. But, as we reserve an active metadata block group, we no longer want to select a metadata block group. So, skip it in the loop. CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.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>
43 hoursbtrfs: error on missing block group when unaccounting log tree extent buffersFilipe Manana1-12/+7
commit fc5799986fbca957e2e3c0480027f249951b7bcf upstream. Currently we only log an error message if we can't find the block group for a log tree extent buffer when unaccounting it (while freeing a log tree). A missing block group means something is seriously wrong and we end up leaking space from the metadata space info. So return -ENOENT in case we don't find the block group. CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Qu Wenruo <wqu@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>
43 hoursbtrfs: fix log tree replay failure due to file with 0 links and extentsFilipe Manana1-18/+30
commit 0a32e4f0025a74c70dcab4478e9b29c22f5ecf2f upstream. If we log a new inode (not persisted in a past transaction) that has 0 links and extents, then log another inode with an higher inode number, we end up with failing to replay the log tree with -EINVAL. The steps for this are: 1) create new file A 2) write some data to file A 3) open an fd on file A 4) unlink file A 5) fsync file A using the previously open fd 6) create file B (has higher inode number than file A) 7) fsync file B 8) power fail before current transaction commits Now when attempting to mount the fs, the log replay will fail with -ENOENT at replay_one_extent() when attempting to replay the first extent of file A. The failure comes when trying to open the inode for file A in the subvolume tree, since it doesn't exist. Before commit 5f61b961599a ("btrfs: fix inode lookup error handling during log replay"), the returned error was -EIO instead of -ENOENT, since we converted any errors when attempting to read an inode during log replay to -EIO. The reason for this is that the log replay procedure fails to ignore the current inode when we are at the stage LOG_WALK_REPLAY_ALL, our current inode has 0 links and last inode we processed in the previous stage has a non 0 link count. In other words, the issue is that at replay_one_extent() we only update wc->ignore_cur_inode if the current replay stage is LOG_WALK_REPLAY_INODES. Fix this by updating wc->ignore_cur_inode whenever we find an inode item regardless of the current replay stage. This is a simple solution and easy to backport, but later we can do other alternatives like avoid logging extents or inode items other than the inode item for inodes with a link count of 0. The problem with the wc->ignore_cur_inode logic has been around since commit f2d72f42d5fa ("Btrfs: fix warning when replaying log after fsync of a tmpfile") but it only became frequent to hit since the more recent commit 5e85262e542d ("btrfs: fix fsync of files with no hard links not persisting deletion"), because we stopped skipping inodes with a link count of 0 when logging, while before the problem would only be triggered if trying to replay a log tree created with an older kernel which has a logged inode with 0 links. A test case for fstests will be submitted soon. Reported-by: Peter Jung <ptr1337@cachyos.org> Link: https://lore.kernel.org/linux-btrfs/fce139db-4458-4788-bb97-c29acf6cb1df@cachyos.org/ Reported-by: burneddi <burneddi@protonmail.com> Link: https://lore.kernel.org/linux-btrfs/lh4W-Lwc0Mbk-QvBhhQyZxf6VbM3E8VtIvU3fPIQgweP_Q1n7wtlUZQc33sYlCKYd-o6rryJQfhHaNAOWWRKxpAXhM8NZPojzsJPyHMf2qY=@protonmail.com/#t Reported-by: Russell Haley <yumpusamongus@gmail.com> Link: https://lore.kernel.org/linux-btrfs/598ecc75-eb80-41b3-83c2-f2317fbb9864@gmail.com/ Fixes: f2d72f42d5fa ("Btrfs: fix warning when replaying log after fsync of a tmpfile") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Boris Burkov <boris@bur.io> 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>
43 hoursbtrfs: clear dirty status from extent buffer on error at insert_new_root()Filipe Manana1-0/+1
commit c0d013495a80cbb53e2288af7ae0ec4170aafd7c upstream. If we failed to insert the tree mod log operation, we are not removing the dirty status from the allocated and dirtied extent buffer before we free it. Removing the dirty status is needed for several reasons such as to adjust the fs_info->dirty_metadata_bytes counter and remove the dirty status from the respective folios. So add the missing call to btrfs_clear_buffer_dirty(). Fixes: f61aa7ba08ab ("btrfs: do not BUG_ON() on tree mod log failure at insert_new_root()") CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Boris Burkov <boris@bur.io> 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>
43 hoursbtrfs: don't skip remaining extrefs if dir not found during log replayFilipe Manana1-4/+14
commit 24e066ded45b8147b79c7455ac43a5bff7b5f378 upstream. During log replay, at add_inode_ref(), if we have an extref item that contains multiple extrefs and one of them points to a directory that does not exist in the subvolume tree, we are supposed to ignore it and process the remaining extrefs encoded in the extref item, since each extref can point to a different parent inode. However when that happens we just return from the function and ignore the remaining extrefs. The problem has been around since extrefs were introduced, in commit f186373fef00 ("btrfs: extended inode refs"), but it's hard to hit in practice because getting extref items encoding multiple extref requires getting a hash collision when computing the offset of the extref's key. The offset if computed like this: key.offset = btrfs_extref_hash(dir_ino, name->name, name->len); and btrfs_extref_hash() is just a wrapper around crc32c(). Fix this by moving to next iteration of the loop when we don't find the parent directory that an extref points to. Fixes: f186373fef00 ("btrfs: extended inode refs") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Boris Burkov <boris@bur.io> 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>
43 hoursbtrfs: qgroup: fix qgroup create ioctl returning success after quotas disabledFilipe Manana2-5/+4
commit 08530d6e638427e7e1344bd67bacc03882ba95b9 upstream. When quotas are disabled qgroup ioctls are supposed to return -ENOTCONN, but the qgroup create ioctl stopped doing that when it races with a quota disable operation, returning 0 instead. This change of behaviour happened in commit 6ed05643ddb1 ("btrfs: create qgroup earlier in snapshot creation"). The issue happens as follows: 1) Task A enters btrfs_ioctl_qgroup_create(), qgroups are enabled and so qgroup_enabled() returns true since fs_info->quota_root is not NULL; 2) Task B enters btrfs_ioctl_quota_ctl() -> btrfs_quota_disable() and disables qgroups, so now fs_info->quota_root is NULL; 3) Task A enters btrfs_create_qgroup() and calls btrfs_qgroup_mode(), which returns BTRFS_QGROUP_MODE_DISABLED since quotas are disabled, and then btrfs_create_qgroup() returns 0 to the caller, which makes the ioctl return 0 instead of -ENOTCONN. The check for fs_info->quota_root and returning -ENOTCONN if it's NULL is made only after the call btrfs_qgroup_mode(). Fix this by moving the check for disabled quotas with btrfs_qgroup_mode() into transaction.c:create_pending_snapshot(), so that we don't abort the transaction if btrfs_create_qgroup() returns -ENOTCONN and quotas are disabled. Fixes: 6ed05643ddb1 ("btrfs: create qgroup earlier in snapshot creation") CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Qu Wenruo <wqu@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>
43 hoursbtrfs: populate otime when logging an inode itemQu Wenruo1-0/+3
commit 1ef94169db0958d6de39f9ea6e063ce887342e2d upstream. [TEST FAILURE WITH EXPERIMENTAL FEATURES] When running test case generic/508, the test case will fail with the new btrfs shutdown support: generic/508 - output mismatch (see /home/adam/xfstests/results//generic/508.out.bad) # --- tests/generic/508.out 2022-05-11 11:25:30.806666664 +0930 # +++ /home/adam/xfstests/results//generic/508.out.bad 2025-07-02 14:53:22.401824212 +0930 # @@ -1,2 +1,6 @@ # QA output created by 508 # Silence is golden # +Before: # +After : stat.btime = Thu Jan 1 09:30:00 1970 # +Before: # +After : stat.btime = Wed Jul 2 14:53:22 2025 # ... # (Run 'diff -u /home/adam/xfstests/tests/generic/508.out /home/adam/xfstests/results//generic/508.out.bad' to see the entire diff) Ran: generic/508 Failures: generic/508 Failed 1 of 1 tests Please note that the test case requires shutdown support, thus the test case will be skipped using the current upstream kernel, as it doesn't have shutdown ioctl support. [CAUSE] The direct cause the 0 time stamp in the log tree: leaf 30507008 items 2 free space 16057 generation 9 owner TREE_LOG leaf 30507008 flags 0x1(WRITTEN) backref revision 1 checksum stored e522548d checksum calced e522548d fs uuid 57d45451-481e-43e4-aa93-289ad707a3a0 chunk uuid d52bd3fd-5163-4337-98a7-7986993ad398 item 0 key (257 INODE_ITEM 0) itemoff 16123 itemsize 160 generation 9 transid 9 size 0 nbytes 0 block group 0 mode 100644 links 1 uid 0 gid 0 rdev 0 sequence 1 flags 0x0(none) atime 1751432947.492000000 (2025-07-02 14:39:07) ctime 1751432947.492000000 (2025-07-02 14:39:07) mtime 1751432947.492000000 (2025-07-02 14:39:07) otime 0.0 (1970-01-01 09:30:00) <<< But the old fs tree has all the correct time stamp: btrfs-progs v6.12 fs tree key (FS_TREE ROOT_ITEM 0) leaf 30425088 items 2 free space 16061 generation 5 owner FS_TREE leaf 30425088 flags 0x1(WRITTEN) backref revision 1 checksum stored 48f6c57e checksum calced 48f6c57e fs uuid 57d45451-481e-43e4-aa93-289ad707a3a0 chunk uuid d52bd3fd-5163-4337-98a7-7986993ad398 item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160 generation 3 transid 0 size 0 nbytes 16384 block group 0 mode 40755 links 1 uid 0 gid 0 rdev 0 sequence 0 flags 0x0(none) atime 1751432947.0 (2025-07-02 14:39:07) ctime 1751432947.0 (2025-07-02 14:39:07) mtime 1751432947.0 (2025-07-02 14:39:07) otime 1751432947.0 (2025-07-02 14:39:07) <<< The root cause is that fill_inode_item() in tree-log.c is only populating a/c/m time, not the otime (or btime in statx output). Part of the reason is that, the vfs inode only has a/c/m time, no native btime support yet. [FIX] Thankfully btrfs has its otime stored in btrfs_inode::i_otime_sec and btrfs_inode::i_otime_nsec. So what we really need is just fill the otime time stamp in fill_inode_item() of tree-log.c There is another fill_inode_item() in inode.c, which is doing the proper otime population. Fixes: 94edf4ae43a5 ("Btrfs: don't bother committing delayed inode updates when fsyncing") CC: stable@vger.kernel.org Reviewed-by: Filipe Manana <fdmanana@suse.com> 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>
43 hoursbtrfs: fix ssd_spread overallocationBoris Burkov1-16/+17
commit 807d9023e75fc20bfd6dd2ac0408ce4af53f1648 upstream. If the ssd_spread mount option is enabled, then we run the so called clustered allocator for data block groups. In practice, this results in creating a btrfs_free_cluster which caches a block_group and borrows its free extents for allocation. Since the introduction of allocation size classes in 6.1, there has been a bug in the interaction between that feature and ssd_spread. find_free_extent() has a number of nested loops. The loop going over the allocation stages, stored in ffe_ctl->loop and managed by find_free_extent_update_loop(), the loop over the raid levels, and the loop over all the block_groups in a space_info. The size class feature relies on the block_group loop to ensure it gets a chance to see a block_group of a given size class. However, the clustered allocator uses the cached cluster block_group and breaks that loop. Each call to do_allocation() will really just go back to the same cached block_group. Normally, this is OK, as the allocation either succeeds and we don't want to loop any more or it fails, and we clear the cluster and return its space to the block_group. But with size classes, the allocation can succeed, then later fail, outside of do_allocation() due to size class mismatch. That latter failure is not properly handled due to the highly complex multi loop logic. The result is a painful loop where we continue to allocate the same num_bytes from the cluster in a tight loop until it fails and releases the cluster and lets us try a new block_group. But by then, we have skipped great swaths of the available block_groups and are likely to fail to allocate, looping the outer loop. In pathological cases like the reproducer below, the cached block_group is often the very last one, in which case we don't perform this tight bg loop but instead rip through the ffe stages to LOOP_CHUNK_ALLOC and allocate a chunk, which is now the last one, and we enter the tight inner loop until an allocation failure. Then allocation succeeds on the final block_group and if the next allocation is a size mismatch, the exact same thing happens again. Triggering this is as easy as mounting with -o ssd_spread and then running: mount -o ssd_spread $dev $mnt dd if=/dev/zero of=$mnt/big bs=16M count=1 &>/dev/null dd if=/dev/zero of=$mnt/med bs=4M count=1 &>/dev/null sync if you do the two writes + sync in a loop, you can force btrfs to spin an excessive amount on semi-successful clustered allocations, before ultimately failing and advancing to the stage where we force a chunk allocation. This results in 2G of data allocated per iteration, despite only using ~20M of data. By using a small size classed extent, the inner loop takes longer and we can spin for longer. The simplest, shortest term fix to unbreak this is to make the clustered allocator size_class aware in the dumbest way, where it fails on size class mismatch. This may hinder the operation of the clustered allocator, but better hindered than completely broken and terribly overallocating. Further re-design improvements are also in the works. Fixes: 52bb7a2166af ("btrfs: introduce size class to block group allocator") CC: stable@vger.kernel.org # 6.1+ Reported-by: David Sterba <dsterba@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
43 hoursbtrfs: don't ignore inode missing when replaying log treeFilipe Manana1-2/+12
commit 7ebf381a69421a88265d3c49cd0f007ba7336c9d upstream. During log replay, at add_inode_ref(), we return -ENOENT if our current inode isn't found on the subvolume tree or if a parent directory isn't found. The error comes from btrfs_iget_logging() <- btrfs_iget() <- btrfs_read_locked_inode(). The single caller of add_inode_ref(), replay_one_buffer(), ignores an -ENOENT error because it expects that error to mean only that a parent directory wasn't found and that is ok. Before commit 5f61b961599a ("btrfs: fix inode lookup error handling during log replay") we were converting any error when getting a parent directory to -ENOENT and any error when getting the current inode to -EIO, so our caller would fail log replay in case we can't find the current inode. After that commit however in case the current inode is not found we return -ENOENT to the caller and therefore it ignores the critical fact that the current inode was not found in the subvolume tree. Fix this by converting -ENOENT to 0 when we don't find a parent directory, returning -ENOENT when we don't find the current inode and making the caller, replay_one_buffer(), not ignore -ENOENT anymore. Fixes: 5f61b961599a ("btrfs: fix inode lookup error handling during log replay") CC: stable@vger.kernel.org # 6.16 Reviewed-by: Boris Burkov <boris@bur.io> 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>
43 hoursbtrfs: qgroup: set quota enabled bit if quota disable fails flushing ↵Filipe Manana1-2/+5
reservations commit e41c75ca3189341e76e6af64b857c05b68a1d7db upstream. Before waiting for the rescan worker to finish and flushing reservations, we clear the BTRFS_FS_QUOTA_ENABLED flag from fs_info. If we fail flushing reservations we leave with the flag not set which is not correct since quotas are still enabled - we must set back the flag on error paths, such as when we fail to start a transaction, except for error paths that abort a transaction. The reservation flushing happens very early before we do any operation that actually disables quotas and before we start a transaction, so set back BTRFS_FS_QUOTA_ENABLED if it fails. Fixes: af0e2aab3b70 ("btrfs: qgroup: flush reservations during quota disable") CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Qu Wenruo <wqu@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>
43 hoursbtrfs: zoned: do not remove unwritten non-data block groupNaohiro Aota1-2/+25
commit 3061801420469610c8fa6080a950e56770773ef1 upstream. There are some reports of "unable to find chunk map for logical 2147483648 length 16384" error message appears in dmesg. This means some IOs are occurring after a block group is removed. When a metadata tree node is cleaned on a zoned setup, we keep that node still dirty and write it out not to create a write hole. However, this can make a block group's used bytes == 0 while there is a dirty region left. Such an unused block group is moved into the unused_bg list and processed for removal. When the removal succeeds, the block group is removed from the transaction->dirty_bgs list, so the unused dirty nodes in the block group are not sent at the transaction commit time. It will be written at some later time e.g, sync or umount, and causes "unable to find chunk map" errors. This can happen relatively easy on SMR whose zone size is 256MB. However, calling do_zone_finish() on such block group returns -EAGAIN and keep that block group intact, which is why the issue is hidden until now. Fixes: afba2bc036b0 ("btrfs: zoned: implement active zone tracking") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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>
43 hoursbtrfs: abort transaction during log replay if walk_log_tree() failedFilipe Manana1-2/+5
commit 2a5898c4aac67494c2f0f7fe38373c95c371c930 upstream. If we failed walking a log tree during replay, we have a missing transaction abort to prevent committing a transaction where we didn't fully replay all the changes from a log tree and therefore can leave the respective subvolume tree in some inconsistent state. So add the missing transaction abort. CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Qu Wenruo <wqu@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>
43 hoursbtrfs: zoned: use filesystem size not disk size for reclaim decisionJohannes Thumshirn1-2/+1
commit 55f7c65b2f69c7e4cb7aa7c1654a228ccf734fd8 upstream. When deciding if a zoned filesystem is reaching the threshold to reclaim data block groups, look at the size of the filesystem not to potentially total available size of all drives in the filesystem. Especially if a filesystem was created with mkfs' -b option, constraining it to only a portion of the block device, the numbers won't match and potentially garbage collection is kicking in too late. Fixes: 3687fcb0752a ("btrfs: zoned: make auto-reclaim less aggressive") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Tested-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-24btrfs: fix block group refcount race in btrfs_create_pending_block_groups()Boris Burkov1-0/+3
commit 2d8e5168d48a91e7a802d3003e72afb4304bebfa upstream. Block group creation is done in two phases, which results in a slightly unintuitive property: a block group can be allocated/deallocated from after btrfs_make_block_group() adds it to the space_info with btrfs_add_bg_to_space_info(), but before creation is completely completed in btrfs_create_pending_block_groups(). As a result, it is possible for a block group to go unused and have 'btrfs_mark_bg_unused' called on it concurrently with 'btrfs_create_pending_block_groups'. This causes a number of issues, which were fixed with the block group flag 'BLOCK_GROUP_FLAG_NEW'. However, this fix is not quite complete. Since it does not use the unused_bg_lock, it is possible for the following race to occur: btrfs_create_pending_block_groups btrfs_mark_bg_unused if list_empty // false list_del_init clear_bit else if (test_bit) // true list_move_tail And we get into the exact same broken ref count and invalid new_bgs state for transaction cleanup that BLOCK_GROUP_FLAG_NEW was designed to prevent. The broken refcount aspect will result in a warning like: [1272.943527] refcount_t: underflow; use-after-free. [1272.943967] WARNING: CPU: 1 PID: 61 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x110 [1272.944731] Modules linked in: btrfs virtio_net xor zstd_compress raid6_pq null_blk [last unloaded: btrfs] [1272.945550] CPU: 1 UID: 0 PID: 61 Comm: kworker/u32:1 Kdump: loaded Tainted: G W 6.14.0-rc5+ #108 [1272.946368] Tainted: [W]=WARN [1272.946585] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 [1272.947273] Workqueue: btrfs_discard btrfs_discard_workfn [btrfs] [1272.947788] RIP: 0010:refcount_warn_saturate+0xba/0x110 [1272.949532] RSP: 0018:ffffbf1200247df0 EFLAGS: 00010282 [1272.949901] RAX: 0000000000000000 RBX: ffffa14b00e3f800 RCX: 0000000000000000 [1272.950437] RDX: 0000000000000000 RSI: ffffbf1200247c78 RDI: 00000000ffffdfff [1272.950986] RBP: ffffa14b00dc2860 R08: 00000000ffffdfff R09: ffffffff90526268 [1272.951512] R10: ffffffff904762c0 R11: 0000000063666572 R12: ffffa14b00dc28c0 [1272.952024] R13: 0000000000000000 R14: ffffa14b00dc2868 R15: 000001285dcd12c0 [1272.952850] FS: 0000000000000000(0000) GS:ffffa14d33c40000(0000) knlGS:0000000000000000 [1272.953458] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1272.953931] CR2: 00007f838cbda000 CR3: 000000010104e000 CR4: 00000000000006f0 [1272.954474] Call Trace: [1272.954655] <TASK> [1272.954812] ? refcount_warn_saturate+0xba/0x110 [1272.955173] ? __warn.cold+0x93/0xd7 [1272.955487] ? refcount_warn_saturate+0xba/0x110 [1272.955816] ? report_bug+0xe7/0x120 [1272.956103] ? handle_bug+0x53/0x90 [1272.956424] ? exc_invalid_op+0x13/0x60 [1272.956700] ? asm_exc_invalid_op+0x16/0x20 [1272.957011] ? refcount_warn_saturate+0xba/0x110 [1272.957399] btrfs_discard_cancel_work.cold+0x26/0x2b [btrfs] [1272.957853] btrfs_put_block_group.cold+0x5d/0x8e [btrfs] [1272.958289] btrfs_discard_workfn+0x194/0x380 [btrfs] [1272.958729] process_one_work+0x130/0x290 [1272.959026] worker_thread+0x2ea/0x420 [1272.959335] ? __pfx_worker_thread+0x10/0x10 [1272.959644] kthread+0xd7/0x1c0 [1272.959872] ? __pfx_kthread+0x10/0x10 [1272.960172] ret_from_fork+0x30/0x50 [1272.960474] ? __pfx_kthread+0x10/0x10 [1272.960745] ret_from_fork_asm+0x1a/0x30 [1272.961035] </TASK> [1272.961238] ---[ end trace 0000000000000000 ]--- Though we have seen them in the async discard workfn as well. It is most likely to happen after a relocation finishes which cancels discard, tears down the block group, etc. Fix this fully by taking the lock around the list_del_init + clear_bit so that the two are done atomically. Fixes: 0657b20c5a76 ("btrfs: fix use-after-free of new block group that became unused") Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Alva Lan <alvalan9@foxmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-17btrfs: fix assertion when building free space treeFilipe Manana1-4/+12
[ Upstream commit 1961d20f6fa8903266ed9bd77c691924c22c8f02 ] When building the free space tree with the block group tree feature enabled, we can hit an assertion failure like this: BTRFS info (device loop0 state M): rebuilding free space tree assertion failed: ret == 0, in fs/btrfs/free-space-tree.c:1102 ------------[ cut here ]------------ kernel BUG at fs/btrfs/free-space-tree.c:1102! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP Modules linked in: CPU: 1 UID: 0 PID: 6592 Comm: syz-executor322 Not tainted 6.15.0-rc7-syzkaller-gd7fa1af5b33e #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102 lr : populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102 sp : ffff8000a4ce7600 x29: ffff8000a4ce76e0 x28: ffff0000c9bc6000 x27: ffff0000ddfff3d8 x26: ffff0000ddfff378 x25: dfff800000000000 x24: 0000000000000001 x23: ffff8000a4ce7660 x22: ffff70001499cecc x21: ffff0000e1d8c160 x20: ffff0000e1cb7800 x19: ffff0000e1d8c0b0 x18: 00000000ffffffff x17: ffff800092f39000 x16: ffff80008ad27e48 x15: ffff700011e740c0 x14: 1ffff00011e740c0 x13: 0000000000000004 x12: ffffffffffffffff x11: ffff700011e740c0 x10: 0000000000ff0100 x9 : 94ef24f55d2dbc00 x8 : 94ef24f55d2dbc00 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff8000a4ce6f98 x4 : ffff80008f415ba0 x3 : ffff800080548ef0 x2 : 0000000000000000 x1 : 0000000100000000 x0 : 000000000000003e Call trace: populate_free_space_tree+0x514/0x518 fs/btrfs/free-space-tree.c:1102 (P) btrfs_rebuild_free_space_tree+0x14c/0x54c fs/btrfs/free-space-tree.c:1337 btrfs_start_pre_rw_mount+0xa78/0xe10 fs/btrfs/disk-io.c:3074 btrfs_remount_rw fs/btrfs/super.c:1319 [inline] btrfs_reconfigure+0x828/0x2418 fs/btrfs/super.c:1543 reconfigure_super+0x1d4/0x6f0 fs/super.c:1083 do_remount fs/namespace.c:3365 [inline] path_mount+0xb34/0xde0 fs/namespace.c:4200 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount fs/namespace.c:4409 [inline] __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4409 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Code: f0047182 91178042 528089c3 9771d47b (d4210000) ---[ end trace 0000000000000000 ]--- This happens because we are processing an empty block group, which has no extents allocated from it, there are no items for this block group, including the block group item since block group items are stored in a dedicated tree when using the block group tree feature. It also means this is the block group with the highest start offset, so there are no higher keys in the extent root, hence btrfs_search_slot_for_read() returns 1 (no higher key found). Fix this by asserting 'ret' is 0 only if the block group tree feature is not enabled, in which case we should find a block group item for the block group since it's stored in the extent root and block group item keys are greater than extent item keys (the value for BTRFS_BLOCK_GROUP_ITEM_KEY is 192 and for BTRFS_EXTENT_ITEM_KEY and BTRFS_METADATA_ITEM_KEY the values are 168 and 169 respectively). In case 'ret' is 1, we just need to add a record to the free space tree which spans the whole block group, and we can achieve this by making 'ret == 0' as the while loop's condition. Reported-by: syzbot+36fae25c35159a763a2a@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/6841dca8.a00a0220.d4325.0020.GAE@google.com/ Reviewed-by: Qu Wenruo <wqu@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: Sasha Levin <sashal@kernel.org>
2025-07-10btrfs: fix wrong start offset for delalloc space release during mmap writeFilipe Manana1-1/+1
[ Upstream commit 17a85f520469a1838379de8ad24f63e778f7c277 ] If we're doing a mmap write against a folio that has i_size somewhere in the middle and we have multiple sectors in the folio, we may have to release excess space previously reserved, for the range going from the rounded up (to sector size) i_size to the folio's end offset. We are calculating the right amount to release and passing it to btrfs_delalloc_release_space(), but we are passing the wrong start offset of that range - we're passing the folio's start offset instead of the end offset, plus 1, of the range for which we keep the reservation. This may result in releasing more space then we should and eventually trigger an underflow of the data space_info's bytes_may_use counter. So fix this by passing the start offset as 'end + 1' instead of 'page_start' to btrfs_delalloc_release_space(). Fixes: d0b7da88f640 ("Btrfs: btrfs_page_mkwrite: Reserve space in sectorsized units") Reviewed-by: Qu Wenruo <wqu@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: Sasha Levin <sashal@kernel.org>
2025-07-10btrfs: prepare btrfs_page_mkwrite() for large foliosQu Wenruo1-9/+10
[ Upstream commit 49990d8fa27d75f8ecf4ad013b13de3c4b1ff433 ] This changes the assumption that the folio is always page sized. (Although the ASSERT() for folio order is still kept as-is). Just replace the PAGE_SIZE with folio_size(). Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: 17a85f520469 ("btrfs: fix wrong start offset for delalloc space release during mmap write") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10btrfs: use btrfs_record_snapshot_destroy() during rmdirFilipe Manana1-1/+1
[ Upstream commit 157501b0469969fc1ba53add5049575aadd79d80 ] We are setting the parent directory's last_unlink_trans directly which may result in a concurrent task starting to log the directory not see the update and therefore can log the directory after we removed a child directory which had a snapshot within instead of falling back to a transaction commit. Replaying such a log tree would result in a mount failure since we can't currently delete snapshots (and subvolumes) during log replay. This is the type of failure described in commit 1ec9a1ae1e30 ("Btrfs: fix unreplayable log after snapshot delete + parent dir fsync"). Fix this by using btrfs_record_snapshot_destroy() which updates the last_unlink_trans field while holding the inode's log_mutex lock. Fixes: 44f714dae50a ("Btrfs: improve performance on fsync against new inode after rename/unlink") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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>
2025-07-10btrfs: propagate last_unlink_trans earlier when doing a rmdirFilipe Manana1-18/+18
[ Upstream commit c466e33e729a0ee017d10d919cba18f503853c60 ] In case the removed directory had a snapshot that was deleted, we are propagating its inode's last_unlink_trans to the parent directory after we removed the entry from the parent directory. This leaves a small race window where someone can log the parent directory after we removed the entry and before we updated last_unlink_trans, and as a result if we ever try to replay such a log tree, we will fail since we will attempt to remove a snapshot during log replay, which is currently not possible and results in the log replay (and mount) to fail. This is the type of failure described in commit 1ec9a1ae1e30 ("Btrfs: fix unreplayable log after snapshot delete + parent dir fsync"). So fix this by propagating the last_unlink_trans to the parent directory before we remove the entry from it. Fixes: 44f714dae50a ("Btrfs: improve performance on fsync against new inode after rename/unlink") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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>
2025-07-10btrfs: record new subvolume in parent dir earlier to avoid dir logging racesFilipe Manana2-2/+4
[ Upstream commit bf5bcf9a6fa070ec8a725b08db63fb1318f77366 ] Instead of recording that a new subvolume was created in a directory after we add the entry do the directory, record it before adding the entry. This is to avoid races where after creating the entry and before recording the new subvolume in the directory (the call to btrfs_record_new_subvolume()), another task logs the directory, so we end up with a log tree where we logged a directory that has an entry pointing to a root that was not yet committed, resulting in an invalid entry if the log is persisted and replayed later due to a power failure or crash. Also state this requirement in the function comment for btrfs_record_new_subvolume(), similar to what we do for the btrfs_record_unlink_dir() and btrfs_record_snapshot_destroy(). Fixes: 45c4102f0d82 ("btrfs: avoid transaction commit on any fsync after subvolume creation") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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>
2025-07-10btrfs: fix inode lookup error handling during log replayFilipe Manana1-65/+62
[ Upstream commit 5f61b961599acbd2bed028d3089105a1f7d224b8 ] When replaying log trees we use read_one_inode() to get an inode, which is just a wrapper around btrfs_iget_logging(), which in turn is a wrapper for btrfs_iget(). But read_one_inode() always returns NULL for any error that btrfs_iget_logging() / btrfs_iget() may return and this is a problem because: 1) In many callers of read_one_inode() we convert the NULL into -EIO, which is not accurate since btrfs_iget() may return -ENOMEM and -ENOENT for example, besides -EIO and other errors. So during log replay we may end up reporting a false -EIO, which is confusing since we may not have had any IO error at all; 2) When replaying directory deletes, at replay_dir_deletes(), we assume the NULL returned from read_one_inode() means that the inode doesn't exist and then proceed as if no error had happened. This is wrong because unless btrfs_iget() returned ERR_PTR(-ENOENT), we had an actual error and the target inode may exist in the target subvolume root - this may later result in the log replay code failing at a later stage (if we are "lucky") or succeed but leaving some inconsistency in the filesystem. So fix this by not ignoring errors from btrfs_iget_logging() and as a consequence remove the read_one_inode() wrapper and just use btrfs_iget_logging() directly. Also since btrfs_iget_logging() is supposed to be called only against subvolume roots, just like read_one_inode() which had a comment about it, add an assertion to btrfs_iget_logging() to check that the target root corresponds to a subvolume root. Fixes: 5d4f98a28c7d ("Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE)") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-07-10btrfs: fix invalid inode pointer dereferences during log replayFilipe Manana1-8/+6
[ Upstream commit 2dcf838cf5c2f0f4501edaa1680fcad03618d760 ] In a few places where we call read_one_inode(), if we get a NULL pointer we end up jumping into an error path, or fallthrough in case of __add_inode_ref(), where we then do something like this: iput(&inode->vfs_inode); which results in an invalid inode pointer that triggers an invalid memory access, resulting in a crash. Fix this by making sure we don't do such dereferences. Fixes: b4c50cbb01a1 ("btrfs: return a btrfs_inode from read_one_inode()") CC: stable@vger.kernel.org # 6.15+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: 5f61b961599a ("btrfs: fix inode lookup error handling during log replay") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10btrfs: return a btrfs_inode from read_one_inode()Filipe Manana1-79/+73
[ Upstream commit b4c50cbb01a1b6901d2b94469636dd80fa93de81 ] All callers of read_one_inode() are mostly interested in the btrfs_inode structure rather than the VFS inode, so make read_one_inode() return the btrfs_inode instead, avoiding lots of BTRFS_I() calls. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: 5f61b961599a ("btrfs: fix inode lookup error handling during log replay") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10btrfs: return a btrfs_inode from btrfs_iget_logging()Filipe Manana1-49/+45
[ Upstream commit a488d8ac2c4d96ecc7da59bb35a573277204ac6b ] All callers of btrfs_iget_logging() are interested in the btrfs_inode structure rather than the VFS inode, so make btrfs_iget_logging() return the btrfs_inode instead, avoiding lots of BTRFS_I() calls. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: 5f61b961599a ("btrfs: fix inode lookup error handling during log replay") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-10btrfs: fix iteration of extrefs during log replayFilipe Manana1-2/+2
[ Upstream commit 54a7081ed168b72a8a2d6ef4ba3a1259705a2926 ] At __inode_add_ref() when processing extrefs, if we jump into the next label we have an undefined value of victim_name.len, since we haven't initialized it before we did the goto. This results in an invalid memory access in the next iteration of the loop since victim_name.len was not initialized to the length of the name of the current extref. Fix this by initializing victim_name.len with the current extref's name length. Fixes: e43eec81c516 ("btrfs: use struct qstr instead of name and namelen pairs") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-07-10btrfs: fix missing error handling when searching for inode refs during log ↵Filipe Manana1-1/+3
replay [ Upstream commit 6561a40ceced9082f50c374a22d5966cf9fc5f5c ] During log replay, at __add_inode_ref(), when we are searching for inode ref keys we totally ignore if btrfs_search_slot() returns an error. This may make a log replay succeed when there was an actual error and leave some metadata inconsistency in a subvolume tree. Fix this by checking if an error was returned from btrfs_search_slot() and if so, return it to the caller. Fixes: e02119d5a7b4 ("Btrfs: Add a write ahead tree log to optimize synchronous operations") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-07-06btrfs: fix use-after-free on inode when scanning root during em shrinkingSasha Levin1-1/+2
[ Upstream commit 59f37036bb7ab3d554c24abc856aabca01126414 ] At btrfs_scan_root() we are accessing the inode's root (and fs_info) in a call to btrfs_fs_closing() after we have scheduled the inode for a delayed iput, and that can result in a use-after-free on the inode in case the cleaner kthread does the iput before we dereference the inode in the call to btrfs_fs_closing(). Fix this by using the fs_info stored already in a local variable instead of doing inode->root->fs_info. Fixes: 102044384056 ("btrfs: make the extent map shrinker run asynchronously as a work queue job") CC: stable@vger.kernel.org # 6.13+ Tested-by: Ivan Shapovalov <intelfx@intelfx.name> Link: https://lore.kernel.org/linux-btrfs/0414d690ac5680d0d77dfc930606cdc36e42e12f.camel@intelfx.name/ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-07-06btrfs: zoned: fix extent range end unlock in cow_file_range()Naohiro Aota1-2/+7
[ Upstream commit 5a4041f2c47247575a6c2e53ce14f7b0ac946c33 ] Running generic/751 on the for-next branch often results in a hang like below. They are both stack by locking an extent. This suggests someone forget to unlock an extent. INFO: task kworker/u128:1:12 blocked for more than 323 seconds. Not tainted 6.13.0-BTRFS-ZNS+ #503 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u128:1 state:D stack:0 pid:12 tgid:12 ppid:2 flags:0x00004000 Workqueue: btrfs-fixup btrfs_work_helper [btrfs] Call Trace: <TASK> __schedule+0x534/0xdd0 schedule+0x39/0x140 __lock_extent+0x31b/0x380 [btrfs] ? __pfx_autoremove_wake_function+0x10/0x10 btrfs_writepage_fixup_worker+0xf1/0x3a0 [btrfs] btrfs_work_helper+0xff/0x480 [btrfs] ? lock_release+0x178/0x2c0 process_one_work+0x1ee/0x570 ? srso_return_thunk+0x5/0x5f worker_thread+0x1d1/0x3b0 ? __pfx_worker_thread+0x10/0x10 kthread+0x10b/0x230 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x30/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> INFO: task kworker/u134:0:184 blocked for more than 323 seconds. Not tainted 6.13.0-BTRFS-ZNS+ #503 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u134:0 state:D stack:0 pid:184 tgid:184 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-btrfs-4) Call Trace: <TASK> __schedule+0x534/0xdd0 schedule+0x39/0x140 __lock_extent+0x31b/0x380 [btrfs] ? __pfx_autoremove_wake_function+0x10/0x10 find_lock_delalloc_range+0xdb/0x260 [btrfs] writepage_delalloc+0x12f/0x500 [btrfs] ? srso_return_thunk+0x5/0x5f extent_write_cache_pages+0x232/0x840 [btrfs] btrfs_writepages+0x72/0x130 [btrfs] do_writepages+0xe7/0x260 ? srso_return_thunk+0x5/0x5f ? lock_acquire+0xd2/0x300 ? srso_return_thunk+0x5/0x5f ? find_held_lock+0x2b/0x80 ? wbc_attach_and_unlock_inode.part.0+0x102/0x250 ? wbc_attach_and_unlock_inode.part.0+0x102/0x250 __writeback_single_inode+0x5c/0x4b0 writeback_sb_inodes+0x22d/0x550 __writeback_inodes_wb+0x4c/0xe0 wb_writeback+0x2f6/0x3f0 wb_workfn+0x32a/0x510 process_one_work+0x1ee/0x570 ? srso_return_thunk+0x5/0x5f worker_thread+0x1d1/0x3b0 ? __pfx_worker_thread+0x10/0x10 kthread+0x10b/0x230 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x30/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> This happens because we have another success path for the zoned mode. When there is no active zone available, btrfs_reserve_extent() returns -EAGAIN. In this case, we have two reactions. (1) If the given range is never allocated, we can only wait for someone to finish a zone, so wait on BTRFS_FS_NEED_ZONE_FINISH bit and retry afterward. (2) Or, if some allocations are already done, we must bail out and let the caller to send IOs for the allocation. This is because these IOs may be necessary to finish a zone. The commit 06f364284794 ("btrfs: do proper folio cleanup when cow_file_range() failed") moved the unlock code from the inside of the loop to the outside. So, previously, the allocated extents are unlocked just after the allocation and so before returning from the function. However, they are no longer unlocked on the case (2) above. That caused the hang issue. Fix the issue by modifying the 'end' to the end of the allocated range. Then, we can exit the loop and the same unlock code can properly handle the case. Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Fixes: 06f364284794 ("btrfs: do proper folio cleanup when cow_file_range() failed") CC: stable@vger.kernel.org Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06btrfs: do regular iput instead of delayed iput during extent map shrinkingFilipe Manana1-1/+1
[ Upstream commit 15b3b3254d1453a8db038b7d44b311a2d6c71f98 ] The extent map shrinker now runs in the system unbound workqueue and no longer in kswapd context so it can directly do an iput() on inodes even if that blocks or needs to acquire any lock (we aren't holding any locks when requesting the delayed iput from the shrinker). So we don't need to add a delayed iput, wake up the cleaner and delegate the iput() to the cleaner, which also adds extra contention on the spinlock that protects the delayed iputs list. Reported-by: Ivan Shapovalov <intelfx@intelfx.name> Tested-by: Ivan Shapovalov <intelfx@intelfx.name> Link: https://lore.kernel.org/linux-btrfs/0414d690ac5680d0d77dfc930606cdc36e42e12f.camel@intelfx.name/ CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-07-06btrfs: make the extent map shrinker run asynchronously as a work queue jobFilipe Manana5-19/+52
[ Upstream commit 1020443840569535f6025a855958f07ea3eebf71 ] Currently the extent map shrinker is run synchronously for kswapd tasks that end up calling the fs shrinker (fs/super.c:super_cache_scan()). This has some disadvantages and for some heavy workloads with memory pressure it can cause some delays and stalls that make a machine unresponsive for some periods. This happens because: 1) We can have several kswapd tasks on machines with multiple NUMA zones, and running the extent map shrinker concurrently can cause high contention on some spin locks, namely the spin locks that protect the radix tree that tracks roots, the per root xarray that tracks open inodes and the list of delayed iputs. This not only delays the shrinker but also causes high CPU consumption and makes the task running the shrinker monopolize a core, resulting in the symptoms of an unresponsive system. This was noted in previous commits such as commit ae1e766f623f ("btrfs: only run the extent map shrinker from kswapd tasks"); 2) The extent map shrinker's iteration over inodes can often be slow, even after changing the data structure that tracks open inodes for a root from a red black tree (up to kernel 6.10) to an xarray (kernel 6.10+). The transition to the xarray while it made things a bit faster, it's still somewhat slow - for example in a test scenario with 10000 inodes that have no extent maps loaded, the extent map shrinker took between 5ms to 8ms, using a release, non-debug kernel. Iterating over the extent maps of an inode can also be slow if have an inode with many thousands of extent maps, since we use a red black tree to track and search extent maps. So having the extent map shrinker run synchronously adds extra delay for other things a kswapd task does. So make the extent map shrinker run asynchronously as a job for the system unbounded workqueue, just like what we do for data and metadata space reclaim jobs. 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>
2025-07-06btrfs: skip inodes without loaded extent maps when shrinking extent mapsFilipe Manana1-21/+57
[ Upstream commit c6c9c4d56483d941f567eb921434c25fc6086dfa ] If there are inodes that don't have any loaded extent maps, we end up grabbing a reference on them and later adding a delayed iput, which wakes up the cleaner and makes it do unnecessary work. This is common when for example the inodes were open only to run stat(2) or all their extent maps were already released through the folio release callback (btrfs_release_folio()) or released by a previous run of the shrinker, or directories which never have extent maps. Reported-by: Ivan Shapovalov <intelfx@intelfx.name> Tested-by: Ivan Shapovalov <intelfx@intelfx.name> Link: https://lore.kernel.org/linux-btrfs/0414d690ac5680d0d77dfc930606cdc36e42e12f.camel@intelfx.name/ CC: stable@vger.kernel.org # 6.13+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-07-06btrfs: do proper folio cleanup when cow_file_range() failedQu Wenruo1-40/+37
[ Upstream commit 06f364284794f149d2abc167c11d556cf20c954b ] [BUG] When testing with COW fixup marked as BUG_ON() (this is involved with the new pin_user_pages*() change, which should not result new out-of-band dirty pages), I hit a crash triggered by the BUG_ON() from hitting COW fixup path. This BUG_ON() happens just after a failed btrfs_run_delalloc_range(): BTRFS error (device dm-2): failed to run delalloc range, root 348 ino 405 folio 65536 submit_bitmap 6-15 start 90112 len 106496: -28 ------------[ cut here ]------------ kernel BUG at fs/btrfs/extent_io.c:1444! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 0 UID: 0 PID: 434621 Comm: kworker/u24:8 Tainted: G OE 6.12.0-rc7-custom+ #86 Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: events_unbound btrfs_async_reclaim_data_space [btrfs] pc : extent_writepage_io+0x2d4/0x308 [btrfs] lr : extent_writepage_io+0x2d4/0x308 [btrfs] Call trace: extent_writepage_io+0x2d4/0x308 [btrfs] extent_writepage+0x218/0x330 [btrfs] extent_write_cache_pages+0x1d4/0x4b0 [btrfs] btrfs_writepages+0x94/0x150 [btrfs] do_writepages+0x74/0x190 filemap_fdatawrite_wbc+0x88/0xc8 start_delalloc_inodes+0x180/0x3b0 [btrfs] btrfs_start_delalloc_roots+0x174/0x280 [btrfs] shrink_delalloc+0x114/0x280 [btrfs] flush_space+0x250/0x2f8 [btrfs] btrfs_async_reclaim_data_space+0x180/0x228 [btrfs] process_one_work+0x164/0x408 worker_thread+0x25c/0x388 kthread+0x100/0x118 ret_from_fork+0x10/0x20 Code: aa1403e1 9402f3ef aa1403e0 9402f36f (d4210000) ---[ end trace 0000000000000000 ]--- [CAUSE] That failure is mostly from cow_file_range(), where we can hit -ENOSPC. Although the -ENOSPC is already a bug related to our space reservation code, let's just focus on the error handling. For example, we have the following dirty range [0, 64K) of an inode, with 4K sector size and 4K page size: 0 16K 32K 48K 64K |///////////////////////////////////////| |#######################################| Where |///| means page are still dirty, and |###| means the extent io tree has EXTENT_DELALLOC flag. - Enter extent_writepage() for page 0 - Enter btrfs_run_delalloc_range() for range [0, 64K) - Enter cow_file_range() for range [0, 64K) - Function btrfs_reserve_extent() only reserved one 16K extent So we created extent map and ordered extent for range [0, 16K) 0 16K 32K 48K 64K |////////|//////////////////////////////| |<- OE ->|##############################| And range [0, 16K) has its delalloc flag cleared. But since we haven't yet submit any bio, involved 4 pages are still dirty. - Function btrfs_reserve_extent() returns with -ENOSPC Now we have to run error cleanup, which will clear all EXTENT_DELALLOC* flags and clear the dirty flags for the remaining ranges: 0 16K 32K 48K 64K |////////| | | | | Note that range [0, 16K) still has its pages dirty. - Some time later, writeback is triggered again for the range [0, 16K) since the page range still has dirty flags. - btrfs_run_delalloc_range() will do nothing because there is no EXTENT_DELALLOC flag. - extent_writepage_io() finds page 0 has no ordered flag Which falls into the COW fixup path, triggering the BUG_ON(). Unfortunately this error handling bug dates back to the introduction of btrfs. Thankfully with the abuse of COW fixup, at least it won't crash the kernel. [FIX] Instead of immediately unlocking the extent and folios, we keep the extent and folios locked until either erroring out or the whole delalloc range finished. When the whole delalloc range finished without error, we just unlock the whole range with PAGE_SET_ORDERED (and PAGE_UNLOCK for !keep_locked cases), with EXTENT_DELALLOC and EXTENT_LOCKED cleared. And the involved folios will be properly submitted, with their dirty flags cleared during submission. For the error path, it will be a little more complex: - The range with ordered extent allocated (range (1)) We only clear the EXTENT_DELALLOC and EXTENT_LOCKED, as the remaining flags are cleaned up by btrfs_mark_ordered_io_finished()->btrfs_finish_one_ordered(). For folios we finish the IO (clear dirty, start writeback and immediately finish the writeback) and unlock the folios. - The range with reserved extent but no ordered extent (range(2)) - The range we never touched (range(3)) For both range (2) and range(3) the behavior is not changed. Now even if cow_file_range() failed halfway with some successfully reserved extents/ordered extents, we will keep all folios clean, so there will be no future writeback triggered on them. CC: stable@vger.kernel.org Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06btrfs: update superblock's device bytes_used when dropping chunkMark Harmstone1-0/+6
commit ae4477f937569d097ca5dbce92a89ba384b49bc6 upstream. Each superblock contains a copy of the device item for that device. In a transaction which drops a chunk but doesn't create any new ones, we were correctly updating the device item in the chunk tree but not copying over the new bytes_used value to the superblock. This can be seen by doing the following: # dd if=/dev/zero of=test bs=4096 count=2621440 # mkfs.btrfs test # mount test /root/temp # cd /root/temp # for i in {00..10}; do dd if=/dev/zero of=$i bs=4096 count=32768; done # sync # rm * # sync # btrfs balance start -dusage=0 . # sync # cd # umount /root/temp # btrfs check test For btrfs-check to detect this, you will also need my patch at https://github.com/kdave/btrfs-progs/pull/991. Change btrfs_remove_dev_extents() so that it adds the devices to the fs_info->post_commit_list if they're not there already. This causes btrfs_commit_device_sizes() to be called, which updates the bytes_used value in the superblock. Fixes: bbbf7243d62d ("btrfs: combine device update operations during transaction commit") CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Mark Harmstone <maharmstone@fb.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>
2025-07-06btrfs: fix a race between renames and directory loggingFilipe Manana1-17/+64
commit 3ca864de852bc91007b32d2a0d48993724f4abad upstream. We have a race between a rename and directory inode logging that if it happens and we crash/power fail before the rename completes, the next time the filesystem is mounted, the log replay code will end up deleting the file that was being renamed. This is best explained following a step by step analysis of an interleaving of steps that lead into this situation. Consider the initial conditions: 1) We are at transaction N; 2) We have directories A and B created in a past transaction (< N); 3) We have inode X corresponding to a file that has 2 hardlinks, one in directory A and the other in directory B, so we'll name them as "A/foo_link1" and "B/foo_link2". Both hard links were persisted in a past transaction (< N); 4) We have inode Y corresponding to a file that as a single hard link and is located in directory A, we'll name it as "A/bar". This file was also persisted in a past transaction (< N). The steps leading to a file loss are the following and for all of them we are under transaction N: 1) Link "A/foo_link1" is removed, so inode's X last_unlink_trans field is updated to N, through btrfs_unlink() -> btrfs_record_unlink_dir(); 2) Task A starts a rename for inode Y, with the goal of renaming from "A/bar" to "A/baz", so we enter btrfs_rename(); 3) Task A inserts the new BTRFS_INODE_REF_KEY for inode Y by calling btrfs_insert_inode_ref(); 4) Because the rename happens in the same directory, we don't set the last_unlink_trans field of directoty A's inode to the current transaction id, that is, we don't cal btrfs_record_unlink_dir(); 5) Task A then removes the entries from directory A (BTRFS_DIR_ITEM_KEY and BTRFS_DIR_INDEX_KEY items) when calling __btrfs_unlink_inode() (actually the dir index item is added as a delayed item, but the effect is the same); 6) Now before task A adds the new entry "A/baz" to directory A by calling btrfs_add_link(), another task, task B is logging inode X; 7) Task B starts a fsync of inode X and after logging inode X, at btrfs_log_inode_parent() it calls btrfs_log_all_parents(), since inode X has a last_unlink_trans value of N, set at in step 1; 8) At btrfs_log_all_parents() we search for all parent directories of inode X using the commit root, so we find directories A and B and log them. Bu when logging direct A, we don't have a dir index item for inode Y anymore, neither the old name "A/bar" nor for the new name "A/baz" since the rename has deleted the old name but has not yet inserted the new name - task A hasn't called yet btrfs_add_link() to do that. Note that logging directory A doesn't fallback to a transaction commit because its last_unlink_trans has a lower value than the current transaction's id (see step 4); 9) Task B finishes logging directories A and B and gets back to btrfs_sync_file() where it calls btrfs_sync_log() to persist the log tree; 10) Task B successfully persisted the log tree, btrfs_sync_log() completed with success, and a power failure happened. We have a log tree without any directory entry for inode Y, so the log replay code deletes the entry for inode Y, name "A/bar", from the subvolume tree since it doesn't exist in the log tree and the log tree is authorative for its index (we logged a BTRFS_DIR_LOG_INDEX_KEY item that covers the index range for the dentry that corresponds to "A/bar"). Since there's no other hard link for inode Y and the log replay code deletes the name "A/bar", the file is lost. The issue wouldn't happen if task B synced the log only after task A called btrfs_log_new_name(), which would update the log with the new name for inode Y ("A/bar"). Fix this by pinning the log root during renames before removing the old directory entry, and unpinning after btrfs_log_new_name() is called. Fixes: 259c4b96d78d ("btrfs: stop doing unnecessary log updates during a rename") CC: stable@vger.kernel.org # 5.18+ Reviewed-by: Boris Burkov <boris@bur.io> 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>
2025-07-06btrfs: fix qgroup reservation leak on failure to allocate ordered extentFilipe Manana1-3/+9
[ Upstream commit 1f2889f5594a2bc4c6a52634c4a51b93e785def5 ] If we fail to allocate an ordered extent for a COW write we end up leaking a qgroup data reservation since we called btrfs_qgroup_release_data() but we didn't call btrfs_qgroup_free_refroot() (which would happen when running the respective data delayed ref created by ordered extent completion or when finishing the ordered extent in case an error happened). So make sure we call btrfs_qgroup_free_refroot() if we fail to allocate an ordered extent for a COW write. Fixes: 7dbeaad0af7d ("btrfs: change timing for qgroup reserved space for ordered extents to fix reserved space leak") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-07-06btrfs: use unsigned types for constants defined as bit shiftsDavid Sterba8-20/+19
[ Upstream commit 05a6ec865d091fe8244657df8063f74e704d1711 ] The unsigned type is a recommended practice (CWE-190, CWE-194) for bit shifts to avoid problems with potential unwanted sign extensions. Although there are no such cases in btrfs codebase, follow the recommendation. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: 1f2889f5594a ("btrfs: fix qgroup reservation leak on failure to allocate ordered extent") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06btrfs: factor out nocow ordered extent and extent map generation into a helperQu Wenruo1-61/+61
[ Upstream commit 10326fdcb3ace2f2dcbc8b9fc50b87e5cab93345 ] Currently we're doing all the ordered extent and extent map generation inside a while() loop of run_delalloc_nocow(). This makes it pretty hard to read, nor doing proper error handling. So move that part of code into a helper, nocow_one_range(). This should not change anything, but there is a tiny timing change where btrfs_dec_nocow_writers() is only called after nocow_one_range() helper exits. This timing change is small, and makes error handling easier, thus should be fine. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: 1f2889f5594a ("btrfs: fix qgroup reservation leak on failure to allocate ordered extent") Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-07-06btrfs: handle csum tree error with rescue=ibadroots correctlyQu Wenruo1-2/+1
[ Upstream commit 547e836661554dcfa15c212a3821664e85b4191a ] [BUG] There is syzbot based reproducer that can crash the kernel, with the following call trace: (With some debug output added) DEBUG: rescue=ibadroots parsed BTRFS: device fsid 14d642db-7b15-43e4-81e6-4b8fac6a25f8 devid 1 transid 8 /dev/loop0 (7:0) scanned by repro (1010) BTRFS info (device loop0): first mount of filesystem 14d642db-7b15-43e4-81e6-4b8fac6a25f8 BTRFS info (device loop0): using blake2b (blake2b-256-generic) checksum algorithm BTRFS info (device loop0): using free-space-tree BTRFS warning (device loop0): checksum verify failed on logical 5312512 mirror 1 wanted 0xb043382657aede36608fd3386d6b001692ff406164733d94e2d9a180412c6003 found 0x810ceb2bacb7f0f9eb2bf3b2b15c02af867cb35ad450898169f3b1f0bd818651 level 0 DEBUG: read tree root path failed for tree csum, ret=-5 BTRFS warning (device loop0): checksum verify failed on logical 5328896 mirror 1 wanted 0x51be4e8b303da58e6340226815b70e3a93592dac3f30dd510c7517454de8567a found 0x51be4e8b303da58e634022a315b70e3a93592dac3f30dd510c7517454de8567a level 0 BTRFS warning (device loop0): checksum verify failed on logical 5292032 mirror 1 wanted 0x1924ccd683be9efc2fa98582ef58760e3848e9043db8649ee382681e220cdee4 found 0x0cb6184f6e8799d9f8cb335dccd1d1832da1071d12290dab3b85b587ecacca6e level 0 process 'repro' launched './file2' with NULL argv: empty string added DEBUG: no csum root, idatacsums=0 ibadroots=134217728 Oops: general protection fault, probably for non-canonical address 0xdffffc0000000041: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000208-0x000000000000020f] CPU: 5 UID: 0 PID: 1010 Comm: repro Tainted: G OE 6.15.0-custom+ #249 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022 RIP: 0010:btrfs_lookup_csum+0x93/0x3d0 [btrfs] Call Trace: <TASK> btrfs_lookup_bio_sums+0x47a/0xdf0 [btrfs] btrfs_submit_bbio+0x43e/0x1a80 [btrfs] submit_one_bio+0xde/0x160 [btrfs] btrfs_readahead+0x498/0x6a0 [btrfs] read_pages+0x1c3/0xb20 page_cache_ra_order+0x4b5/0xc20 filemap_get_pages+0x2d3/0x19e0 filemap_read+0x314/0xde0 __kernel_read+0x35b/0x900 bprm_execve+0x62e/0x1140 do_execveat_common.isra.0+0x3fc/0x520 __x64_sys_execveat+0xdc/0x130 do_syscall_64+0x54/0x1d0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ---[ end trace 0000000000000000 ]--- [CAUSE] Firstly the fs has a corrupted csum tree root, thus to mount the fs we have to go "ro,rescue=ibadroots" mount option. Normally with that mount option, a bad csum tree root should set BTRFS_FS_STATE_NO_DATA_CSUMS flag, so that any future data read will ignore csum search. But in this particular case, we have the following call trace that caused NULL csum root, but not setting BTRFS_FS_STATE_NO_DATA_CSUMS: load_global_roots_objectid(): ret = btrfs_search_slot(); /* Succeeded */ btrfs_item_key_to_cpu() found = true; /* We found the root item for csum tree. */ root = read_tree_root_path(); if (IS_ERR(root)) { if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) /* * Since we have rescue=ibadroots mount option, * @ret is still 0. */ break; if (!found || ret) { /* @found is true, @ret is 0, error handling for csum * tree is skipped. */ } This means we completely skipped to set BTRFS_FS_STATE_NO_DATA_CSUMS if the csum tree is corrupted, which results unexpected later csum lookup. [FIX] If read_tree_root_path() failed, always populate @ret to the error number. As at the end of the function, we need @ret to determine if we need to do the extra error handling for csum tree. Fixes: abed4aaae4f7 ("btrfs: track the csum, extent, and free space trees in a rb tree") Reported-by: Zhiyu Zhang <zhiyuzhang999@gmail.com> Reported-by: Longxing Li <coregee2000@gmail.com> Reviewed-by: David Sterba <dsterba@suse.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>
2025-06-19btrfs: exit after state split error at set_extent_bit()Filipe Manana1-1/+4
[ Upstream commit 41d69d4d78d8b179bf3bcdfc56d28a12b3a608d2 ] If split_state() returned an error we call extent_io_tree_panic() which will trigger a BUG() call. However if CONFIG_BUG is disabled, which is an uncommon and exotic scenario, then we fallthrough and hit a use after free when calling set_state_bits() since the extent state record which the local variable 'prealloc' points to was freed by split_state(). So jump to the label 'out' after calling extent_io_tree_panic() and set the 'prealloc' pointer to NULL since split_state() has already freed it when it hit an error. 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: Sasha Levin <sashal@kernel.org>
2025-06-19btrfs: exit after state insertion failure at btrfs_convert_extent_bit()Filipe Manana1-0/+1
[ Upstream commit 3bf179e36da917c5d9bec71c714573ed1649b7c1 ] If insert_state() state failed it returns an error pointer and we call extent_io_tree_panic() which will trigger a BUG() call. However if CONFIG_BUG is disabled, which is an uncommon and exotic scenario, then we fallthrough and call cache_state() which will dereference the error pointer, resulting in an invalid memory access. So jump to the 'out' label after calling extent_io_tree_panic(), it also makes the code more clear besides dealing with the exotic scenario where CONFIG_BUG is disabled. 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: Sasha Levin <sashal@kernel.org>
2025-06-19btrfs: fix invalid data space release when truncating block in NOCOW modeFilipe Manana1-2/+5
[ Upstream commit d3914d6030aa6be2993dfc223d096ff93018c236 ] If when truncating a block we fail to reserve data space and then we proceed anyway because we can do a NOCOW write, if we later get an error when trying to get the folio from the inode's mapping, we end up releasing data space that we haven't reserved, screwing up the bytes_may_use counter from the data space_info, eventually resulting in an underflow when all other reservations done by other tasks are released, if any, or right away if there are no other reservations at the moment. This is because when we get an error when trying to grab the block's folio we call btrfs_delalloc_release_space(), which releases metadata (which we have reserved) and data (which we haven't reserved). Fix this by calling btrfs_delalloc_release_space() only if we did reserve data space, that is, if we aren't falling back to NOCOW, meaning the local variable @only_release_metadata has a false value, otherwise release only metadata by calling btrfs_delalloc_release_metadata(). Fixes: 6d4572a9d71d ("btrfs: allow btrfs_truncate_block() to fallback to nocow for data space reservation") Reviewed-by: Qu Wenruo <wqu@suse.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>
2025-06-19btrfs: scrub: fix a wrong error type when metadata bytenr mismatchesQu Wenruo1-1/+1
[ Upstream commit f2c19541e421b3235efc515dad88b581f00592ae ] When the bytenr doesn't match for a metadata tree block, we will report it as an csum error, which is incorrect and should be reported as a metadata error instead. Fixes: a3ddbaebc7c9 ("btrfs: scrub: introduce a helper to verify one metadata block") 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: Sasha Levin <sashal@kernel.org>
2025-06-19btrfs: scrub: update device stats when an error is detectedQu Wenruo1-3/+29
[ Upstream commit ec1f3a207cdf314eae4d4ae145f1ffdb829f0652 ] [BUG] Since the migration to the new scrub_stripe interface, scrub no longer updates the device stats when hitting an error, no matter if it's a read or checksum mismatch error. E.g: BTRFS info (device dm-2): scrub: started on devid 1 BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488 BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file) BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488 BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file) BTRFS info (device dm-2): scrub: finished on devid 1 with status: 0 Note there is no line showing the device stats error update. [CAUSE] In the migration to the new scrub_stripe interface, we no longer call btrfs_dev_stat_inc_and_print(). [FIX] - Introduce a new bitmap for metadata generation errors * A new bitmap @meta_gen_error_bitmap is introduced to record which blocks have metadata generation mismatch errors. * A new counter for that bitmap @init_nr_meta_gen_errors, is also introduced to store the number of generation mismatch errors that are found during the initial read. This is for the error reporting at scrub_stripe_report_errors(). * New dedicated error message for unrepaired generation mismatches * Update @meta_gen_error_bitmap if a transid mismatch is hit - Add btrfs_dev_stat_inc_and_print() calls to the following call sites * scrub_stripe_report_errors() * scrub_write_endio() This is only for the write errors. This means there is a minor behavior change: - The timing of device stats error message Since we concentrate the error messages at scrub_stripe_report_errors(), the device stats error messages will all show up in one go, after the detailed scrub error messages: BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488 BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file) BTRFS error (device dm-2): unable to fixup (regular) error at logical 13631488 on dev /dev/mapper/test-scratch1 physical 13631488 BTRFS warning (device dm-2): checksum error at logical 13631488 on dev /dev/mapper/test-scratch1, physical 13631488, root 5, inode 257, offset 0, length 4096, links 1 (path: file) BTRFS error (device dm-2): bdev /dev/mapper/test-scratch1 errs: wr 0, rd 0, flush 0, corrupt 1, gen 0 BTRFS error (device dm-2): bdev /dev/mapper/test-scratch1 errs: wr 0, rd 0, flush 0, corrupt 2, gen 0 Fixes: e02ee89baa66 ("btrfs: scrub: switch scrub_simple_mirror() to scrub_stripe infrastructure") Reviewed-by: Filipe Manana <fdmanana@suse.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>
2025-05-29btrfs: avoid NULL pointer dereference if no valid csum treeQu Wenruo1-2/+2
[ Upstream commit f95d186255b319c48a365d47b69bd997fecb674e ] [BUG] When trying read-only scrub on a btrfs with rescue=idatacsums mount option, it will crash with the following call trace: BUG: kernel NULL pointer dereference, address: 0000000000000208 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page CPU: 1 UID: 0 PID: 835 Comm: btrfs Tainted: G O 6.15.0-rc3-custom+ #236 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022 RIP: 0010:btrfs_lookup_csums_bitmap+0x49/0x480 [btrfs] Call Trace: <TASK> scrub_find_fill_first_stripe+0x35b/0x3d0 [btrfs] scrub_simple_mirror+0x175/0x290 [btrfs] scrub_stripe+0x5f7/0x6f0 [btrfs] scrub_chunk+0x9a/0x150 [btrfs] scrub_enumerate_chunks+0x333/0x660 [btrfs] btrfs_scrub_dev+0x23e/0x600 [btrfs] btrfs_ioctl+0x1dcf/0x2f80 [btrfs] __x64_sys_ioctl+0x97/0xc0 do_syscall_64+0x4f/0x120 entry_SYSCALL_64_after_hwframe+0x76/0x7e [CAUSE] Mount option "rescue=idatacsums" will completely skip loading the csum tree, so that any data read will not find any data csum thus we will ignore data checksum verification. Normally call sites utilizing csum tree will check the fs state flag NO_DATA_CSUMS bit, but unfortunately scrub does not check that bit at all. This results in scrub to call btrfs_search_slot() on a NULL pointer and triggered above crash. [FIX] Check both extent and csum tree root before doing any tree search. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> 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: Sasha Levin <sashal@kernel.org>
2025-05-29btrfs: handle empty eb->folios in num_extent_folios()Boris Burkov1-0/+2
[ Upstream commit d6fe0c69b3aa5c985380b794bdf8e6e9b1811e60 ] num_extent_folios() unconditionally calls folio_order() on eb->folios[0]. If that is NULL this will be a segfault. It is reasonable for it to return 0 as the number of folios in the eb when the first entry is NULL, so do that instead. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29btrfs: compression: adjust cb->compressed_folios allocation typeKees Cook1-1/+1
[ Upstream commit 6f9a8ab796c6528d22de3c504c81fce7dde63d8a ] In preparation for making the kmalloc() family of allocators type aware, we need to make sure that the returned type from the allocation matches the type of the variable being assigned. (Before, the allocator would always return "void *", which can be implicitly cast to any pointer type.) The assigned type is "struct folio **" but the returned type will be "struct page **". These are the same allocation size (pointer size), but the types don't match. Adjust the allocation type to match the assignment. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Kees Cook <kees@kernel.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-29btrfs: send: return -ENAMETOOLONG when attempting a path that is too longFilipe Manana1-4/+2
[ Upstream commit a77749b3e21813566cea050bbb3414ae74562eba ] When attempting to build a too long path we are currently returning -ENOMEM, which is very odd and misleading. So update fs_path_ensure_buf() to return -ENAMETOOLONG instead. Also, while at it, move the WARN_ON() into the if statement's expression, as it makes it clear what is being tested and also has the effect of adding 'unlikely' to the statement, which allows the compiler to generate better code as this condition is never expected to happen. 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: Sasha Levin <sashal@kernel.org>
2025-05-29btrfs: get zone unusable bytes while holding lock at btrfs_reclaim_bgs_work()Filipe Manana1-7/+11
[ Upstream commit 1283b8c125a83bf7a7dbe90c33d3472b6d7bf612 ] At btrfs_reclaim_bgs_work(), we are grabbing a block group's zone unusable bytes while not under the protection of the block group's spinlock, so this can trigger race reports from KCSAN (or similar tools) since that field is typically updated while holding the lock, such as at __btrfs_add_free_space_zoned() for example. Fix this by grabbing the zone unusable bytes while we are still in the critical section holding the block group's spinlock, which is right above where we are currently grabbing it. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.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: Sasha Levin <sashal@kernel.org>