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f2fs_destroy_extent_node() does not set FI_NO_EXTENT before clearing
extent nodes. When called from f2fs_drop_inode() with I_SYNC set,
concurrent kworker writeback can insert new extent nodes into the same
extent tree, racing with the destroy and triggering f2fs_bug_on() in
__destroy_extent_node(). The scenario is as follows:
drop inode writeback
- iput
- f2fs_drop_inode // I_SYNC set
- f2fs_destroy_extent_node
- __destroy_extent_node
- while (node_cnt) {
write_lock(&et->lock)
__free_extent_tree
write_unlock(&et->lock)
- __writeback_single_inode
- f2fs_outplace_write_data
- f2fs_update_read_extent_cache
- __update_extent_tree_range
// FI_NO_EXTENT not set,
// insert new extent node
} // node_cnt == 0, exit while
- f2fs_bug_on(node_cnt) // node_cnt > 0
Additionally, __update_extent_tree_range() only checks FI_NO_EXTENT for
EX_READ type, leaving EX_BLOCK_AGE updates completely unprotected.
This patch set FI_NO_EXTENT under et->lock in __destroy_extent_node(),
consistent with other callers (__update_extent_tree_range and
__drop_extent_tree) and check FI_NO_EXTENT for both EX_READ and
EX_BLOCK_AGE tree.
Fixes: 3fc5d5a182f6 ("f2fs: fix to shrink read extent node in batches")
Cc: stable@vger.kernel.org
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The fsparam_string_empty() gives an error when mounting without string, since
its type is set to fsparam_flag in VFS. So, let's allow the flag as well.
This addresses xfstests/f2fs/015 and f2fs/021.
Fixes: d18535132523 ("f2fs: separate the options parsing and options checking")
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The following steps will change previous value of reserve_{blocks,node},
this dones not match the original intention.
1.mount -t f2fs -o reserve_root=8192 imgfile test_mount/
F2FS-fs (loop56): Mounted with checkpoint version = 1b69f8c7
mount info:
/dev/block/loop56 on /data/test_mount type f2fs (xxx,reserve_root=8192,reserve_node=0,resuid=0,resgid=0,xxx)
2.mount -t f2fs -o remount,reserve_root=4096 /data/test_mount
F2FS-fs (loop56): Preserve previous reserve_root=8192
check mount info: reserve_root change to 4096
/dev/block/loop56 on /data/test_mount type f2fs (xxx,reserve_root=4096,reserve_node=0,resuid=0,resgid=0,xxx)
Prior to commit d18535132523 ("f2fs: separate the options parsing and options checking"),
the value of reserve_{blocks,node} was only set during the first mount, along with
the corresponding mount option F2FS_MOUNT_RESERVE_{ROOT,NODE} . If the mount option
F2FS_MOUNT_RESERVE_{ROOT,NODE} was found to have been set during the mount/remount,
the previously value of reserve_{blocks,node} would also be preserved, as shown in
the code below.
if (test_opt(sbi, RESERVE_ROOT)) {
f2fs_info(sbi, "Preserve previous reserve_root=%u",
F2FS_OPTION(sbi).root_reserved_blocks);
} else {
F2FS_OPTION(sbi).root_reserved_blocks = arg;
set_opt(sbi, RESERVE_ROOT);
}
But commit d18535132523 ("f2fs: separate the options parsing and options checking")
only preserved the previous mount option; it did not preserve the previous value of
reserve_{blocks,node}. Since value of reserve_{blocks,node} value is assigned
or not depends on ctx->spec_mask, ctx->spec_mask should be alos handled in
f2fs_check_opt_consistency.
This patch will clear the corresponding ctx->spec_mask bits in f2fs_check_opt_consistency
to preserve the previously values of reserve_{blocks,node} if it already have a value.
Fixes: d18535132523 ("f2fs: separate the options parsing and options checking")
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Neither F2FS nor VFS invalidates the block device page cache, which
results in reading stale metadata. An example scenario is shown below:
Terminal A Terminal B
mount /dev/vdb /mnt/f2fs
touch mx // ino = 4
sync
dump.f2fs -i 4 /dev/vdb// block on "[Y/N]"
touch mx2 // ino = 5
sync
umount /mnt/f2fs
dump.f2fs -i 5 /dev/vdb // block addr is 0
After umount, the block device page cache is not purged, causing
`dump.f2fs -i 5 /dev/vdb` to read stale metadata and see inode 5 with
block address 0.
Btrfs has encountered a similar issue before, the solution there was to
call sync_blockdev() and invalidate_bdev() when the device is closed:
mail-archive.com/linux-btrfs@vger.kernel.org/msg54188.html
For the root user, the f2fs kernel calls sync_blockdev() on umount to
flush all cached data to disk, and f2fs-tools can release the page cache
by issuing ioctl(fd, BLKFLSBUF) when accessing the device. However,
non-root users are not permitted to drop the page cache, and may still
observe stale data.
This patch calls sync_blockdev() and invalidate_bdev() during umount to
invalidate the block device page cache, thereby preventing stale
metadata from being read.
Note that this may result in an extra sync_blockdev() call on the first
device, in both f2fs_put_super() and kill_block_super(). The second call
do nothing, as there are no dirty pages left to flush. It ensures that
non-root users do not observe stale data.
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Suspend can fail if kernel threads do not freeze for a while.
f2fs_gc and f2fs_discard threads can perform long-running operations
that prevent them from reaching a freeze point in a timely manner.
This patch adds explicit freezing checks in the following locations:
1. f2fs_gc: Added a check at the 'retry' label to exit the loop quickly
if freezing is requested, especially during heavy GC rounds.
2. __issue_discard_cmd: Added a 'suspended' flag to break both inner and
outer loops during discard command issuance if freezing is detected
after at least one command has been issued.
3. __issue_discard_cmd_orderly: Added a similar check for orderly discard
to ensure responsiveness.
These checks ensure that the threads release locks safely and enter the
frozen state.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
syzbot reported a f2fs bug as below:
BUG: KMSAN: uninit-value in f2fs_sanity_check_node_footer+0x374/0xa20 fs/f2fs/node.c:1520
f2fs_sanity_check_node_footer+0x374/0xa20 fs/f2fs/node.c:1520
f2fs_finish_read_bio+0xe1e/0x1d60 fs/f2fs/data.c:177
f2fs_read_end_io+0x6ab/0x2220 fs/f2fs/data.c:-1
bio_endio+0x1006/0x1160 block/bio.c:1792
submit_bio_noacct+0x533/0x2960 block/blk-core.c:891
submit_bio+0x57a/0x620 block/blk-core.c:926
blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline]
f2fs_submit_read_bio+0x12c/0x360 fs/f2fs/data.c:557
f2fs_submit_page_bio+0xee2/0x1450 fs/f2fs/data.c:775
read_node_folio+0x384/0x4b0 fs/f2fs/node.c:1481
__get_node_folio+0x5db/0x15d0 fs/f2fs/node.c:1576
f2fs_get_inode_folio+0x40/0x50 fs/f2fs/node.c:1623
do_read_inode fs/f2fs/inode.c:425 [inline]
f2fs_iget+0x1209/0x9380 fs/f2fs/inode.c:596
f2fs_fill_super+0x8f5a/0xb2e0 fs/f2fs/super.c:5184
get_tree_bdev_flags+0x6e6/0x920 fs/super.c:1694
get_tree_bdev+0x38/0x50 fs/super.c:1717
f2fs_get_tree+0x35/0x40 fs/f2fs/super.c:5436
vfs_get_tree+0xb3/0x5d0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3763 [inline]
do_new_mount+0x885/0x1dd0 fs/namespace.c:3839
path_mount+0x7a2/0x20b0 fs/namespace.c:4159
do_mount fs/namespace.c:4172 [inline]
__do_sys_mount fs/namespace.c:4361 [inline]
__se_sys_mount+0x704/0x7f0 fs/namespace.c:4338
__x64_sys_mount+0xe4/0x150 fs/namespace.c:4338
x64_sys_call+0x39f0/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The root cause is: in f2fs_finish_read_bio(), we may access uninit data
in folio if we failed to read the data from device into folio, let's add
a check condition to avoid such issue.
Cc: stable@kernel.org
Fixes: 50ac3ecd8e05 ("f2fs: fix to do sanity check on node footer in {read,write}_end_io")
Reported-by: syzbot+9aac813cdc456cdd49f8@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-f2fs-devel/69a9ca26.a70a0220.305d9a.0000.GAE@google.com
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
lockdep reported a potential deadlock:
a) TCMU device removal context:
- call del_gendisk() to get q->q_usage_counter
- call start_flush_work() to get work_completion of wb->dwork
b) f2fs writeback context:
- in wb_workfn(), which holds work_completion of wb->dwork
- call f2fs_balance_fs() to get sbi->gc_lock
c) f2fs vfs_write context:
- call f2fs_gc() to get sbi->gc_lock
- call f2fs_write_checkpoint() to get sbi->cp_global_sem
d) f2fs mount context:
- call recover_fsync_data() to get sbi->cp_global_sem
- call f2fs_check_and_fix_write_pointer() to call blkdev_report_zones()
that goes down to blk_mq_alloc_request and get q->q_usage_counter
Original callstack is in Closes tag.
However, I think this is a false alarm due to before mount returns
successfully (context d), we can not access file therein via vfs_write
(context c).
Let's introduce per-sb cp_global_sem_key, and assign the key for
cp_global_sem, so that lockdep can recognize cp_global_sem from
different super block correctly.
A lot of work are done by Shin'ichiro Kawasaki, thanks a lot for
the work.
Fixes: c426d99127b1 ("f2fs: Check write pointer consistency of open zones")
Cc: stable@kernel.org
Reported-and-tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Closes: https://lore.kernel.org/linux-f2fs-devel/20260218125237.3340441-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Data loss can occur when fsync is performed on a newly created file
(before any checkpoint has been written) concurrently with a checkpoint
operation. The scenario is as follows:
create & write & fsync 'file A' write checkpoint
- f2fs_do_sync_file // inline inode
- f2fs_write_inode // inode folio is dirty
- f2fs_write_checkpoint
- f2fs_flush_merged_writes
- f2fs_sync_node_pages
- f2fs_flush_nat_entries
- f2fs_fsync_node_pages // no dirty node
- f2fs_need_inode_block_update // return false
SPO and lost 'file A'
f2fs_flush_nat_entries() sets the IS_CHECKPOINTED and HAS_LAST_FSYNC
flags for the nat_entry, but this does not mean that the checkpoint has
actually completed successfully. However, f2fs_need_inode_block_update()
checks these flags and incorrectly assumes that the checkpoint has
finished.
The root cause is that the semantics of IS_CHECKPOINTED and
HAS_LAST_FSYNC are only guaranteed after the checkpoint write fully
completes.
This patch modifies f2fs_need_inode_block_update() to acquire the
sbi->node_write lock before reading the nat_entry flags, ensuring that
once IS_CHECKPOINTED and HAS_LAST_FSYNC are observed to be set, the
checkpoint operation has already completed.
Fixes: e05df3b115e7 ("f2fs: add node operations")
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In age-based victim selection (ATGC, AT_SSR, or GC_CB), f2fs_get_victim
can encounter sections with zero valid blocks. This situation often
arises when checkpoint is disabled or due to race conditions between
SIT updates and dirty list management.
In such cases, f2fs_get_section_mtime() returns INVALID_MTIME, which
subsequently triggers a fatal f2fs_bug_on(sbi, mtime == INVALID_MTIME)
in add_victim_entry() or get_cb_cost().
This patch adds a check in f2fs_get_victim's selection loop to skip
sections with no valid blocks. This prevents unnecessary age
calculations for empty sections and avoids the associated kernel panic.
This change also allows removing redundant checks in add_victim_entry().
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When f2fs_fiemap() is called with `fileinfo->fi_flags` containing the
FIEMAP_FLAG_SYNC flag, it attempts to write data to disk before
retrieving file mappings via filemap_write_and_wait(). However, there is
an issue where the file does not get mapped as expected. The following
scenario can occur:
root@vm:/mnt/f2fs# dd if=/dev/zero of=data.3k bs=3k count=1
root@vm:/mnt/f2fs# xfs_io data.3k -c "fiemap -v 0 4096"
data.3k:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..5]: 0..5 6 0x307
The root cause of this issue is that f2fs_write_single_data_page() only
calls f2fs_write_inline_data() to copy data from the data folio to the
inode folio, and it clears the dirty flag on the data folio. However, it
does not mark the data folio as writeback. When
__filemap_fdatawait_range() checks for folios with the writeback flag,
it returns early, causing f2fs_fiemap() to report that the file has no
mapping.
To fix this issue, the solution is to call
f2fs_write_single_node_folio() in f2fs_inline_data_fiemap() when
getting fiemap with FIEMAP_FLAG_SYNC flags. This patch ensures that the
inode folio is written back and the writeback process completes before
proceeding.
Cc: stable@kernel.org
Fixes: 9ffe0fb5f3bb ("f2fs: handle inline data operations")
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
During FGGC node block migration, fsck may incorrectly treat the
migrated node block as fsync-written data.
The reproduction scenario:
root@vm:/mnt/f2fs# seq 1 2048 | xargs -n 1 ./test_sync // write inline inode and sync
root@vm:/mnt/f2fs# rm -f 1
root@vm:/mnt/f2fs# sync
root@vm:/mnt/f2fs# f2fs_io gc_range // move data block in sync mode and not write CP
SPO, "fsck --dry-run" find inode has already checkpointed but still
with DENT_BIT_SHIFT set
The root cause is that GC does not clear the dentry mark and fsync mark
during node block migration, leading fsck to misinterpret them as
user-issued fsync writes.
In BGGC mode, node block migration is handled by f2fs_sync_node_pages(),
which guarantees the dentry and fsync marks are cleared before writing.
This patch move the set/clear of the fsync|dentry marks into
__write_node_folio to make the logic clearer, and ensures the
fsync|dentry mark is cleared in FGGC.
Cc: stable@kernel.org
Fixes: da011cc0da8c ("f2fs: move node pages only in victim section during GC")
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs_need_dentry_mark() reads nat_entry flags without mutual exclusion
with the checkpoint path, which can result in an incorrect inode block
marking state. The scenario is as follows:
create & write & fsync 'file A' write checkpoint
- f2fs_do_sync_file // inline inode
- f2fs_write_inode // inode folio is dirty
- f2fs_write_checkpoint
- f2fs_flush_merged_writes
- f2fs_sync_node_pages
- f2fs_fsync_node_pages // no dirty node
- f2fs_need_inode_block_update // return true
- f2fs_fsync_node_pages // inode dirtied
- f2fs_need_dentry_mark //return true
- f2fs_flush_nat_entries
- f2fs_write_checkpoint end
- __write_node_folio // inode with DENT_BIT_SHIFT set
SPO, "fsck --dry-run" find inode has already checkpointed but still
with DENT_BIT_SHIFT set
The state observed by f2fs_need_dentry_mark() can differ from the state
observed in __write_node_folio() after acquiring sbi->node_write. The
root cause is that the semantics of IS_CHECKPOINTED and
HAS_FSYNCED_INODE are only guaranteed after the checkpoint write has
fully completed.
This patch moves set_dentry_mark() into __write_node_folio() and
protects it with the sbi->node_write lock.
Cc: stable@kernel.org
Fixes: 88bd02c9472a ("f2fs: fix conditions to remain recovery information in f2fs_sync_file")
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Syzbot reported a f2fs bug as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:1900!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 6527 Comm: syz.5.110 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:f2fs_issue_discard_timeout+0x59b/0x5a0 fs/f2fs/segment.c:1900
Code: d9 80 e1 07 80 c1 03 38 c1 0f 8c d6 fe ff ff 48 89 df e8 a8 5e fa fd e9 c9 fe ff ff e8 4e 46 94 fd 90 0f 0b e8 46 46 94 fd 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc9000494f940 EFLAGS: 00010283
RAX: ffffffff843009ca RBX: 0000000000000001 RCX: 0000000000080000
RDX: ffffc9001ca78000 RSI: 00000000000029f3 RDI: 00000000000029f4
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100893a431 R12: 1ffff1100893a430
R13: 1ffff1100c2b702c R14: dffffc0000000000 R15: ffff8880449d2160
FS: 00007ffa35fed6c0(0000) GS:ffff88812643d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2b68634000 CR3: 0000000039f62000 CR4: 00000000003526f0
Call Trace:
<TASK>
__f2fs_remount fs/f2fs/super.c:2960 [inline]
f2fs_reconfigure+0x108a/0x1710 fs/f2fs/super.c:5443
reconfigure_super+0x227/0x8a0 fs/super.c:1080
do_remount fs/namespace.c:3391 [inline]
path_mount+0xdc5/0x10e0 fs/namespace.c:4151
do_mount fs/namespace.c:4172 [inline]
__do_sys_mount fs/namespace.c:4361 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4338
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffa37dbda0a
The root cause is there will be race condition in between f2fs_ioc_fitrim()
and f2fs_remount():
- f2fs_remount - f2fs_ioc_fitrim
- f2fs_issue_discard_timeout
- __issue_discard_cmd
- __drop_discard_cmd
- __wait_all_discard_cmd
- f2fs_trim_fs
- f2fs_write_checkpoint
- f2fs_clear_prefree_segments
- f2fs_issue_discard
- __issue_discard_async
- __queue_discard_cmd
- __update_discard_tree_range
- __insert_discard_cmd
- __create_discard_cmd
: atomic_inc(&dcc->discard_cmd_cnt);
- sanity check on dcc->discard_cmd_cnt (expect discard_cmd_cnt to be zero)
This will only happen when fitrim races w/ remount rw, if we remount to
readonly filesystem, remount will wait until mnt_pcp.mnt_writers to zero,
that means fitrim is not in process at that time.
Cc: stable@kernel.org
Fixes: 2482c4325dfe ("f2fs: detect bug_on in f2fs_wait_discard_bios")
Reported-by: syzbot+62538b67389ee582837a@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-f2fs-devel/69b07d7c.050a0220.8df7.09a1.GAE@google.com
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch refactors the node footer flag setting code to simplify
redundant logic and adjust function parameters and return types. No
logical changes.
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch refactor the f2fs_move_node_folio() function. No logical
changes.
Cc: stable@kernel.org
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Let's use more generic f2fs_stop_checkpoint() instead of
f2fs_handle_critical_error() to handle critical error in f2fs.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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