linux/fs/btrfs
Boris Burkov d508e56270 btrfs: check folio mapping after unlock in relocate_one_folio()
commit 3e74859ee3 upstream.

When we call btrfs_read_folio() to bring a folio uptodate, we unlock the
folio. The result of that is that a different thread can modify the
mapping (like remove it with invalidate) before we call folio_lock().
This results in an invalid page and we need to try again.

In particular, if we are relocating concurrently with aborting a
transaction, this can result in a crash like the following:

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP
  CPU: 76 PID: 1411631 Comm: kworker/u322:5
  Workqueue: events_unbound btrfs_reclaim_bgs_work
  RIP: 0010:set_page_extent_mapped+0x20/0xb0
  RSP: 0018:ffffc900516a7be8 EFLAGS: 00010246
  RAX: ffffea009e851d08 RBX: ffffea009e0b1880 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: ffffc900516a7b90 RDI: ffffea009e0b1880
  RBP: 0000000003573000 R08: 0000000000000001 R09: ffff88c07fd2f3f0
  R10: 0000000000000000 R11: 0000194754b575be R12: 0000000003572000
  R13: 0000000003572fff R14: 0000000000100cca R15: 0000000005582fff
  FS:  0000000000000000(0000) GS:ffff88c07fd00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 000000407d00f002 CR4: 00000000007706f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
  <TASK>
  ? __die+0x78/0xc0
  ? page_fault_oops+0x2a8/0x3a0
  ? __switch_to+0x133/0x530
  ? wq_worker_running+0xa/0x40
  ? exc_page_fault+0x63/0x130
  ? asm_exc_page_fault+0x22/0x30
  ? set_page_extent_mapped+0x20/0xb0
  relocate_file_extent_cluster+0x1a7/0x940
  relocate_data_extent+0xaf/0x120
  relocate_block_group+0x20f/0x480
  btrfs_relocate_block_group+0x152/0x320
  btrfs_relocate_chunk+0x3d/0x120
  btrfs_reclaim_bgs_work+0x2ae/0x4e0
  process_scheduled_works+0x184/0x370
  worker_thread+0xc6/0x3e0
  ? blk_add_timer+0xb0/0xb0
  kthread+0xae/0xe0
  ? flush_tlb_kernel_range+0x90/0x90
  ret_from_fork+0x2f/0x40
  ? flush_tlb_kernel_range+0x90/0x90
  ret_from_fork_asm+0x11/0x20
  </TASK>

This occurs because cleanup_one_transaction() calls
destroy_delalloc_inodes() which calls invalidate_inode_pages2() which
takes the folio_lock before setting mapping to NULL. We fail to check
this, and subsequently call set_extent_mapping(), which assumes that
mapping != NULL (in fact it asserts that in debug mode)

Note that the "fixes" patch here is not the one that introduced the
race (the very first iteration of this code from 2009) but a more recent
change that made this particular crash happen in practice.

Fixes: e7f1326cc2 ("btrfs: set page extent mapped after read_folio in relocate_one_page")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Qu Wenruo <wqu@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>
History 2025-01-02 10:34:25 +01:00
..
tests btrfs: convert find_lock_delalloc_range() to use a folio 2024-09-10 16:51:14 +02:00
accessors.c move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
accessors.h move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
acl.c btrfs: remove unused included headers 2024-03-04 16:24:46 +01:00
acl.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
async-thread.c btrfs: remove unused included headers 2024-03-04 16:24:46 +01:00
async-thread.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
backref.c btrfs: drop the backref cache during relocation if we commit 2024-10-01 19:10:26 +02:00
backref.h btrfs: uninline some static inline helpers from backref.h 2024-03-04 16:24:53 +01:00
bio.c btrfs: split bios to the fs sector size boundary 2024-12-27 14:02:14 +01:00
bio.h btrfs: fix error propagation of split bios 2024-10-23 18:17:43 +02:00
block-group.c btrfs: zoned: fix zone unusable accounting for freed reserved extent 2024-10-17 16:16:46 +02:00
block-group.h btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
block-rsv.c btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
block-rsv.h btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
btrfs_inode.h btrfs: change btrfs_encoded_read() so that reading of extent is done by caller 2024-12-09 10:40:55 +01:00
compression.c btrfs: convert btrfs_decompress() to take a folio 2024-09-10 16:51:21 +02:00
compression.h btrfs: convert btrfs_decompress() to take a folio 2024-09-10 16:51:21 +02:00
ctree.c btrfs: fix use-after-free when COWing tree bock and tracing is enabled 2025-01-02 10:34:24 +01:00
ctree.h btrfs: fix improper generation check in snapshot delete 2024-12-27 14:02:14 +01:00
defrag.c btrfs: fix defrag not merging contiguous extents due to merged extent maps 2024-10-31 16:46:41 +01:00
defrag.h btrfs: drop transaction parameter from btrfs_add_inode_defrag() 2024-09-10 16:51:19 +02:00
delalloc-space.c btrfs: constify pointer parameters where applicable 2024-07-11 15:33:22 +02:00
delalloc-space.h btrfs: constify pointer parameters where applicable 2024-07-11 15:33:22 +02:00
delayed-inode.c btrfs: pass a btrfs_inode to btrfs_readdir_get_delayed_items() 2024-07-11 15:33:28 +02:00
delayed-inode.h btrfs: pass a btrfs_inode to btrfs_readdir_get_delayed_items() 2024-07-11 15:33:28 +02:00
delayed-ref.c btrfs: fix incorrect comparison for delayed refs 2024-11-14 16:11:02 +01:00
delayed-ref.h btrfs: use sector numbers as keys for the dirty extents xarray 2024-10-11 18:33:35 +02:00
dev-replace.c btrfs: don't take dev_replace rwsem on task already holding it 2024-12-14 20:03:36 +01:00
dev-replace.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
dir-item.c btrfs: fix passing 0 to ERR_PTR in btrfs_search_dir_index_item() 2024-10-22 16:10:55 +02:00
dir-item.h btrfs: constify pointer parameters where applicable 2024-07-11 15:33:22 +02:00
direct-io.c btrfs: do not hold the extent lock for entire read 2024-09-10 16:51:20 +02:00
direct-io.h btrfs: move the direct IO code into its own file 2024-07-11 15:33:29 +02:00
discard.c btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
discard.h btrfs: unexport btrfs_run_discard_work and make it static 2023-06-19 13:59:25 +02:00
disk-io.c btrfs: drop unused parameter options from open_ctree() 2024-12-14 20:04:12 +01:00
disk-io.h btrfs: drop unused parameter options from open_ctree() 2024-12-14 20:04:12 +01:00
export.c btrfs: remove super block argument from btrfs_iget() 2024-07-11 15:33:25 +02:00
export.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
extent-io-tree.c btrfs: introduce EXTENT_DIO_LOCKED 2024-09-10 16:51:20 +02:00
extent-io-tree.h btrfs: introduce EXTENT_DIO_LOCKED 2024-09-10 16:51:20 +02:00
extent-tree.c btrfs: fix improper generation check in snapshot delete 2024-12-27 14:02:14 +01:00
extent-tree.h btrfs: do not BUG_ON() when freeing tree block after error 2024-07-11 15:33:26 +02:00
extent_io.c btrfs: fix the delalloc range locking if sector size < page size 2024-10-22 16:09:44 +02:00
extent_io.h btrfs: convert try_release_extent_mapping() to take a folio 2024-09-10 16:51:21 +02:00
extent_map.c btrfs: fix extent map merging not happening for adjacent extents 2024-10-31 16:45:16 +01:00
extent_map.h btrfs: do not directly include rwlock_types.h 2024-07-11 15:33:22 +02:00
fiemap.c btrfs: initialize last_extent_end to fix -Wmaybe-uninitialized warning in extent_fiemap() 2024-08-26 16:58:13 +02:00
fiemap.h btrfs: move fiemap code into its own file 2024-07-11 15:33:20 +02:00
file-item.c btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
file-item.h btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
file.c btrfs: fix race setting file private on concurrent lseek using same fd 2024-09-17 17:31:48 +02:00
file.h btrfs: move the direct IO code into its own file 2024-07-11 15:33:29 +02:00
free-space-cache.c btrfs: add cancellation points to trim loops 2024-10-07 23:21:56 +02:00
free-space-cache.h btrfs: add cancellation points to trim loops 2024-10-07 23:21:56 +02:00
free-space-tree.c btrfs: do not BUG_ON() when freeing tree block after error 2024-07-11 15:33:26 +02:00
free-space-tree.h btrfs: add forward declarations and headers, part 2 2024-03-04 16:24:49 +01:00
fs.c btrfs: sysfs: update fs features directory asynchronously 2023-02-13 17:50:35 +01:00
fs.h btrfs: don't take dev_replace rwsem on task already holding it 2024-12-14 20:03:36 +01:00
inode-item.c btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
inode-item.h btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
inode.c btrfs: fix swap file activation failure due to extents that used to be shared 2025-01-02 10:34:24 +01:00
ioctl.c btrfs: change btrfs_encoded_read() so that reading of extent is done by caller 2024-12-09 10:40:55 +01:00
ioctl.h btrfs: constify pointer parameters where applicable 2024-07-11 15:33:22 +02:00
Kconfig btrfs: check-integrity: remove CONFIG_BTRFS_FS_CHECK_INTEGRITY option 2023-10-12 16:44:05 +02:00
locking.c btrfs: change root->root_key.objectid to btrfs_root_id() 2024-05-07 21:31:06 +02:00
locking.h btrfs: cleanup recursive include of the same header 2024-07-11 15:33:22 +02:00
lru_cache.c btrfs: fix typos found by codespell 2023-12-15 23:00:04 +01:00
lru_cache.h btrfs: cleanup recursive include of the same header 2024-07-11 15:33:22 +02:00
lzo.c btrfs: convert lzo_decompress() to take a folio 2024-09-10 16:51:21 +02:00
Makefile btrfs: move the direct IO code into its own file 2024-07-11 15:33:29 +02:00
messages.c btrfs: disable rate limiting when debug enabled 2024-10-01 19:29:41 +02:00
messages.h btrfs: constify fs_info parameter in __btrfs_panic() 2023-12-15 20:27:02 +01:00
misc.h btrfs: constify pointer parameters where applicable 2024-07-11 15:33:22 +02:00
ordered-data.c btrfs: add and use helper to verify the calling task has locked the inode 2024-09-10 16:51:22 +02:00
ordered-data.h btrfs: convert btrfs_mark_ordered_io_finished() to take a folio 2024-09-10 16:51:14 +02:00
orphan.c btrfs: BTRFS_PATH_AUTO_FREE in orphan.c 2024-09-10 16:51:22 +02:00
orphan.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
print-tree.c btrfs: avoid using fixed char array size for tree names 2024-08-02 22:44:27 +02:00
print-tree.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
props.c btrfs: pass a btrfs_inode to btrfs_set_prop() 2024-07-11 15:33:29 +02:00
props.h btrfs: pass a btrfs_inode to btrfs_set_prop() 2024-07-11 15:33:29 +02:00
qgroup.c btrfs: fix transaction atomicity bug when enabling simple quotas 2025-01-02 10:34:24 +01:00
qgroup.h btrfs: qgroup: set a more sane default value for subtree drop threshold 2024-10-22 16:09:11 +02:00
raid-stripe-tree.c btrfs: change RST lookup error message level to debug 2024-09-10 16:51:17 +02:00
raid-stripe-tree.h btrfs: remove raid-stripe-tree encoding field from stripe_extent 2024-07-11 15:33:28 +02:00
raid56.c btrfs: rename the extra_gfp parameter of btrfs_alloc_page_array() 2024-07-11 15:33:30 +02:00
raid56.h btrfs: add forward declarations and headers, part 2 2024-03-04 16:24:49 +01:00
rcu-string.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
ref-verify.c btrfs: ref-verify: fix use-after-free after invalid ref action 2024-12-09 10:40:56 +01:00
ref-verify.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
reflink.c btrfs: convert copy_inline_to_page() to use folio 2024-09-10 16:51:21 +02:00
reflink.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
relocation.c btrfs: check folio mapping after unlock in relocate_one_folio() 2025-01-02 10:34:25 +01:00
relocation.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
root-tree.c btrfs: change root->root_key.objectid to btrfs_root_id() 2024-05-07 21:31:06 +02:00
root-tree.h btrfs: qgroup: fix qgroup prealloc rsv leak in subvolume operations 2024-04-02 19:18:23 +02:00
scrub.c btrfs: rename btrfs_submit_bio() to btrfs_submit_bbio() 2024-09-10 16:51:19 +02:00
scrub.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
send.c btrfs: check folio mapping after unlock in put_file_data() 2025-01-02 10:34:25 +01:00
send.h btrfs: pass a btrfs_inode to btrfs_ioctl_send() 2024-07-11 15:33:28 +02:00
space-info.c btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
space-info.h btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
subpage.c btrfs: only unlock the to-be-submitted ranges inside a folio 2024-09-10 16:51:22 +02:00
subpage.h btrfs: only unlock the to-be-submitted ranges inside a folio 2024-09-10 16:51:22 +02:00
super.c btrfs: fix mount failure due to remount races 2024-12-14 20:04:13 +01:00
super.h btrfs: change BTRFS_MOUNT_* flags to 64bit type 2024-07-19 17:20:23 +02:00
sysfs.c btrfs: sysfs: fix direct super block member reads 2025-01-02 10:34:24 +01:00
sysfs.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
transaction.c btrfs: qgroup: use xarray to track dirty extents in transaction 2024-09-10 16:51:18 +02:00
transaction.h btrfs: fix race between direct IO write and fsync when using same fd 2024-09-03 20:29:55 +02:00
tree-checker.c btrfs: tree-checker: reject inline extent items with 0 ref count 2024-12-27 14:02:14 +01:00
tree-checker.h btrfs: make sure that WRITTEN is set on all metadata blocks 2024-05-02 22:11:13 +02:00
tree-log.c btrfs: fix uninitialized pointer free on read_alloc_one_name() error 2024-10-11 19:55:04 +02:00
tree-log.h btrfs: avoid transaction commit on any fsync after subvolume creation 2024-07-11 15:33:24 +02:00
tree-mod-log.c btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
tree-mod-log.h btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
ulist.c btrfs: preallocate ulist memory for qgroup rsv 2024-07-11 15:33:26 +02:00
ulist.h btrfs: preallocate ulist memory for qgroup rsv 2024-07-11 15:33:26 +02:00
uuid-tree.c move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
uuid-tree.h btrfs: move uuid tree related code to uuid-tree.[ch] 2024-09-10 16:51:12 +02:00
verity.c btrfs: add and use helper to verify the calling task has locked the inode 2024-09-10 16:51:22 +02:00
verity.h btrfs: add forward declarations and headers, part 1 2024-03-04 16:24:49 +01:00
volumes.c btrfs: do not clear read-only when adding sprout device 2024-12-14 20:03:36 +01:00
volumes.h btrfs: split remaining space to discard in chunks 2024-10-07 23:21:53 +02:00
xattr.c btrfs: add and use helper to verify the calling task has locked the inode 2024-09-10 16:51:22 +02:00
xattr.h btrfs: constify pointer parameters where applicable 2024-07-11 15:33:22 +02:00
zlib.c btrfs: convert zlib_decompress() to take a folio 2024-09-10 16:51:21 +02:00
zoned.c btrfs: zoned: fix missing RCU locking in error message when loading zone info 2024-10-09 13:23:51 +02:00
zoned.h btrfs: constify more pointer parameters 2024-09-10 16:51:22 +02:00
zstd.c btrfs: convert zstd_decompress() to take a folio 2024-09-10 16:51:21 +02:00