kernel/linux.git/fs/btrfs, branch v6.12.107

btrfs: zoned: fix missing chunk metadata reservation

2026-08-23T12:22:46+00:00

[ Upstream commit 8bc4d7209611e8aa9d5409b6a4a86a9eb91b69a3 ] reserve_chunk_space() stores the return value of btrfs_zoned_activate_one_bg() in ret. The helper can return 1 after successfully activating a block group, but ret is later used to decide whether to reserve metadata for chunk tree updates. As a result, successful activation skips btrfs_block_rsv_add() and leaves trans->chunk_bytes_reserved unchanged. Use a separate variable for the activation result so positive success does not affect the later reservation. Keep activation failures in ret instead of returning early so the function uses the common tail path. Fixes: b6a98021e401 ("btrfs: zoned: activate necessary block group") CC: stable@vger.kernel.org Reviewed-by: Johannes Thumshirn Signed-off-by: Guanghui Yang <3497809730@qq.com> Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: remove fs_info argument from btrfs_zoned_activate_one_bg()

2026-08-23T12:22:45+00:00

[ Upstream commit a232ff90d14657c8637c6e94b606bb5d700a2ecb ] We don't need it since we can grab fs_info from the given space_info. So remove the fs_info argument. Reviewed-by: Johannes Thumshirn Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Stable-dep-of: 8bc4d7209611 ("btrfs: zoned: fix missing chunk metadata reservation") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: add space_info argument to btrfs_chunk_alloc()

2026-08-23T12:22:45+00:00

[ Upstream commit 098a442d5b6d440602604dc1a88706a2a91bce4e ] Take a btrfs_space_info argument in btrfs_chunk_alloc(). New block group will belong to that space_info. Signed-off-by: Naohiro Aota Reviewed-by: David Sterba Signed-off-by: David Sterba Stable-dep-of: 8bc4d7209611 ("btrfs: zoned: fix missing chunk metadata reservation") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: add debug build only WARN

2026-08-23T12:22:45+00:00

[ Upstream commit 3db15c6ca6feb2c5000a1cbb39c33866e0349abd ] Add conditional WARN() wrapper that's enabled only in debug build. It should be used for unexpected conditions that should be noisy. Use it instead of ASSERT(0). As it will not lead to BUG() make sure that continuing is still possible, e.g. the error is handled anyway. Reviewed-by: Josef Bacik Signed-off-by: David Sterba Stable-dep-of: 8bc4d7209611 ("btrfs: zoned: fix missing chunk metadata reservation") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: fix memory leak in btrfs_do_encoded_write()

2026-08-19T16:14:09+00:00

[ Upstream commit d2a4e4e626b2f4670b69b430c357f03f53eb6632 ] Local fuzzing of 6.12.94 has found the following memory leak: Unreferenced object 0xffff888018050a80 (size 64): comm "syz.0.17", pid 10297, jiffies 4294953601 hex dump (first 32 bytes): 00 10 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................ 10 0a 05 18 80 88 ff ff 10 0a 05 18 80 88 ff ff ................ backtrace (crc a8a6fc29): kmemleak_alloc_recursive include/linux/kmemleak.h:42 [inline] slab_post_alloc_hook mm/slub.c:4152 [inline] slab_alloc_node mm/slub.c:4197 [inline] __kmalloc_cache_noprof+0x168/0x2c0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:878 [inline] extent_changeset_alloc fs/btrfs/extent_io.h:207 [inline] qgroup_reserve_data+0x1c5/0x7d0 fs/btrfs/qgroup.c:4305 btrfs_qgroup_reserve_data+0x2e/0xb0 fs/btrfs/qgroup.c:4355 btrfs_do_encoded_write+0x92e/0x1040 fs/btrfs/inode.c:9746 btrfs_encoded_write fs/btrfs/file.c:1482 [inline] btrfs_do_write_iter+0x280/0x610 fs/btrfs/file.c:1507 btrfs_ioctl_encoded_write+0x3d6/0x490 fs/btrfs/ioctl.c:4738 btrfs_ioctl+0x6f9/0xc90 fs/btrfs/ioctl.c:-1 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0xbe/0x1a0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x77/0x7f Unreferenced object 0xffff888018050a00 (size 64): comm "syz.0.17", pid 10297, jiffies 4294953601 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 ff 0f 00 00 00 00 00 00 ................ 90 0a 05 18 80 88 ff ff 90 0a 05 18 80 88 ff ff ................ backtrace (crc cb5c9580): kmemleak_alloc_recursive include/linux/kmemleak.h:42 [inline] slab_post_alloc_hook mm/slub.c:4152 [inline] slab_alloc_node mm/slub.c:4197 [inline] __kmalloc_cache_noprof+0x168/0x2c0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] ulist_prealloc+0x9c/0x110 fs/btrfs/ulist.c:114 extent_changeset_prealloc fs/btrfs/extent_io.h:217 [inline] __set_extent_bit+0x16b/0x1a70 fs/btrfs/extent-io-tree.c:1086 set_record_extent_bits+0x50/0x90 fs/btrfs/extent-io-tree.c:1821 qgroup_reserve_data+0x274/0x7d0 fs/btrfs/qgroup.c:4312 btrfs_qgroup_reserve_data+0x2e/0xb0 fs/btrfs/qgroup.c:4355 btrfs_do_encoded_write+0x92e/0x1040 fs/btrfs/inode.c:9746 btrfs_encoded_write fs/btrfs/file.c:1482 [inline] btrfs_do_write_iter+0x280/0x610 fs/btrfs/file.c:1507 btrfs_ioctl_encoded_write+0x3d6/0x490 fs/btrfs/ioctl.c:4738 btrfs_ioctl+0x6f9/0xc90 fs/btrfs/ioctl.c:-1 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0xbe/0x1a0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fix this by freeing an extent changeset before returning from btrfs_do_encoded_write(). Fixes: 7c0c7269f7b5 ("btrfs: add BTRFS_IOC_ENCODED_WRITE") Reviewed-by: Filipe Manana Signed-off-by: Dmitry Antipov Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: zoned: fix deadlock between metadata writeback and transaction commit

2026-08-09T18:23:02+00:00

[ Upstream commit 1ebe51c29fa9755d5b2fea28727c051117907cf8 ] When writing out metadata extent buffers in a zoned filesystem, btree_writepages() holds fs_info->zoned_meta_io_lock across the whole writeback loop, including the call to btrfs_check_meta_write_pointer() -> check_bg_is_active(). For the tree-log block group, check_bg_is_active() may fail to activate the zone and fall back to btrfs_zone_finish_one_bg() to free an active zone. That path waits for the running transaction to commit while still holding zoned_meta_io_lock, but the committer needs that same lock to write out the tree extents, so the two tasks deadlock: Task A (kworker, metadata writeback) Task B (fsstress, transaction commit) ------------------------------------ ------------------------------------- wb_workfn() btrfs_commit_transaction(T) btree_writepages() btrfs_write_and_wait_transaction() btrfs_zoned_meta_io_lock() btrfs_write_marked_extents() btrfs_check_meta_write_pointer() btree_writepages() check_bg_is_active() [treelog_bg] btrfs_zoned_meta_io_lock() btrfs_zone_finish_one_bg() do_zone_finish() btrfs_inc_block_group_ro() btrfs_wait_for_commit() The sibling branch in check_bg_is_active() already drops zoned_meta_io_lock around do_zone_finish() for this exact reason. Do the same in the tree-log branch: release the lock around btrfs_zone_finish_one_bg() and re-acquire it afterwards. The lock only protects fs_info->active_{meta,system}_bg, which this branch does not touch, and ctx->zoned_bg keeps a reference to the block group across the unlock, so nothing is lost while the lock is dropped. This hang occasionally reproduces with fstests generic/475 on a zoned btrfs filesystem. Fixes: 13bb483d32ab ("btrfs: zoned: activate metadata block group on write time") Reviewed-by: Naohiro Aota Signed-off-by: Johannes Thumshirn Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: fix leaking BTRFS_FS_STATE_REMOUNTING flag

2026-08-09T18:23:02+00:00

[ Upstream commit 6881f45d0eb541f2cee8c37c84b3860a23823bb3 ] [BUG] The following script can lead to unexpected qgroup rescan failure: # mkfs.btrfs -f -O quota $dev # mount $dev $mnt # mount -o remount,rescue=ibadroots $mnt ^^^^^ This above command is expected to fail # btrfs quota rescan -w $mnt ^^^^^ The above qgroup rescan is not expected to fail # btrfs qgroup show $mnt WARNING: qgroup data inconsistent, rescan recommended Qgroupid Referenced Exclusive Path -------- ---------- --------- ---- 0/5 16.00KiB 16.00KiB The above short script will be converted to a proper fstests case. [CAUSE] Inside btrfs_reconfigure(), if either btrfs_check_options() or btrfs_check_features() failed, we will always have BTRFS_FS_STATE_REMOUNTING set for the fs until the next successful remount. That BTRFS_FS_STATE_REMOUNTING flag will interrupt several operations, including: - Qgroup rescan - Auto defrag - Space reclaim [FIX] Change the error handling of btrfs_check_options() and btrfs_check_features() to goto restore label. Fixes: eddb1a433f26 ("btrfs: add reconfigure callback for fs_context") Reviewed-by: Johannes Thumshirn Signed-off-by: Qu Wenruo Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: free mapping node on duplicate reloc root insert

2026-08-03T09:17:08+00:00

[ Upstream commit 6a8269b6459ed870a8156c106a0f597383907872 ] __add_reloc_root() allocates a mapping_node before inserting it into rc->reloc_root_tree. If rb_simple_insert() finds an existing entry, it returns the existing rb_node and leaves the newly allocated node unlinked. The error path then returns -EEXIST without freeing the new node. Since the node was never inserted into reloc_root_tree, the later cleanup in put_reloc_control() cannot find it either. Free the newly allocated node before returning -EEXIST. The callers currently assert that -EEXIST should not happen, so this is a defensive cleanup for an unexpected duplicate insert path. If the path is ever reached, the local allocation should still be released. Fixes: 57a304cfd43b ("btrfs: do not panic in __add_reloc_root") Reviewed-by: Qu Wenruo Signed-off-by: Guanghui Yang <3497809730@qq.com> Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: don't propagate EXTENT_FLAG_LOGGING to split extent maps

2026-08-03T09:17:08+00:00

[ Upstream commit 5eff4d5b17fa1950e80bfd1ba43dc0699e61a644 ] When btrfs_drop_extent_map_range() splits an extent map, the new split maps inherit the original map's flags through a local 'flags' variable. Commit f86f7a75e2fb ("btrfs: use the flags of an extent map to identify the compression type") changed the EXTENT_FLAG_LOGGING clearing to operate on em->flags instead of that local 'flags' copy, so a split of an extent map that is currently being logged wrongly inherits EXTENT_FLAG_LOGGING. The flag is then never cleared on the split, and when it is freed while still on the inode's modified_extents list (for example by the extent map shrinker) it trips the WARN_ON(!list_empty(&em->list)) in btrfs_free_extent_map() and leads to a use-after-free. Clear EXTENT_FLAG_LOGGING from the local 'flags' copy used for the splits and only clear EXTENT_FLAG_PINNED from em->flags, restoring the behaviour prior to f86f7a75e2fb. CC: Jeff Layton Link: https://lore.kernel.org/all/20260629-btrfs-skip-logging-v1-1-4e3a28c1acaf@kernel.org/ Fixes: f86f7a75e2fb ("btrfs: use the flags of an extent map to identify the compression type") Reviewed-by: Jeff Layton Reviewed-by: Filipe Manana Signed-off-by: Leo Martins Signed-off-by: Filipe Manana Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: fix root leak if its reloc root is unexpected in merge_reloc_roots()

2026-08-03T09:17:01+00:00

[ Upstream commit ce6050bafb4e33377dc17fcc357736bfc351180c ] If we have an unexpected reloc_root for our root, we jump to the out label but never drop the reference we obtained for root, resulting in a leak. Add a missing btrfs_put_root() call. Fixes: 24213fa46c70 ("btrfs: do proper error handling in merge_reloc_roots") Reviewed-by: Qu Wenruo Reviewed-by: Johannes Thumshirn Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin