syzbot
WARNING in btree_csum_one_bio (2)
Status:
upstream: reported on 2026/09/09 16:23
Subsystems:
btrfs
Labels:
prio:low
[Documentation on labels]
Reported-by: syzbot+5fd974495fd56ec60faf@syzkaller.appspotmail.com
First crash: 4d03h, last: 4d03h
Sample crash report:
item 7 key (263 EXTENT_DATA 17633280) itemoff 3504 itemsize 53
generation 9 type 1
extent data disk bytenr 6729728 nr 65536
extent data offset 0 nr 65536 ram 65536
extent compression 0
item 8 key (263 EXTENT_DATA 17698816) itemoff 3451 itemsize 53
generation 9 type 1
extent data disk bytenr 6795264 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0
item 9 key (263 EXTENT_DATA 17702912) itemoff 3398 itemsize 53
generation 9 type 1
extent data disk bytenr 6799360 nr 36864
extent data offset 0 nr 36864 ram 36864
extent compression 0
item 10 key (263 EXTENT_DATA 17739776) itemoff 3345 itemsize 53
generation 9 type 1
extent data disk bytenr 6840320 nr 12288
extent data offset 0 nr 12288 ram 12288
extent compression 0
item 11 key (263 EXTENT_DATA 17752064) itemoff 3292 itemsize 53
generation 9 type 1
extent data disk bytenr 6852608 nr 16384
extent data offset 0 nr 16384 ram 16384
extent compression 0
item 12 key (263 EXTENT_DATA 17768448) itemoff 3239 itemsize 53
generation 9 type 1
extent data disk bytenr 6868992 nr 8192
extent data offset 0 nr 8192 ram 8192
extent compression 0
item 13 key (263 EXTENT_DATA 17776640) itemoff 3186 itemsize 53
generation 9 type 1
extent data disk bytenr 6885376 nr 49152
extent data offset 0 nr 49152 ram 49152
extent compression 0
item 14 key (263 EXTENT_DATA 17780736) itemoff 3133 itemsize 53
generation 9 type 1
extent data disk bytenr 6885376 nr 49152
extent data offset 4096 nr 45056 ram 49152
extent compression 0
item 15 key (263 EXTENT_DATA 17825792) itemoff 3080 itemsize 53
generation 9 type 1
extent data disk bytenr 0 nr 0
extent data offset 0 nr 15765504 ram 15765504
extent compression 0
item 16 key (18446744073709551606 EXTENT_CSUM 5279744) itemoff 3016 itemsize 64
range start 5279744 end 5287936 length 8192
BTRFS error (device loop0): block=5324800 write time tree block corruption detected
------------[ cut here ]------------
IS_ENABLED(CONFIG_BTRFS_DEBUG) || btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID
WARNING: fs/btrfs/disk-io.c:328 at btree_csum_one_bio+0x9d6/0xd10 fs/btrfs/disk-io.c:327, CPU#0: kworker/u4:13/1059
Modules linked in:
CPU: 0 UID: 0 PID: 1059 Comm: kworker/u4:13 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: btrfs-worker btrfs_work_helper
RIP: 0010:btree_csum_one_bio+0x9d6/0xd10 fs/btrfs/disk-io.c:327
Code: ff 89 c6 e8 bc ef b0 fd 45 85 f6 75 07 e8 b2 ea b0 fd eb 42 80 3d bc c1 4c 0c 01 75 15 e8 a2 ea b0 fd eb 32 e8 9b ea b0 fd 90 <0f> 0b 90 e9 35 fc ff ff e8 8d ea b0 fd c6 05 99 c1 4c 0c 01 48 c7
RSP: 0018:ffffc90005337920 EFLAGS: 00010293
RAX: ffffffff8416e195 RBX: fffffffffffffffa RCX: ffff88803668a580
RDX: 0000000000000000 RSI: fffffffffffffffa RDI: fffffffffffffffa
RBP: ffffc900053379f8 R08: 5400000000000000 R09: 0000000000000000
R10: 0000000000008000 R11: ffffffff8ec362b8 R12: ffffffff8416de4b
R13: 00000000ffffff8b R14: ffff888011f5505f R15: ffff88801fcc3560
FS: 0000000000000000(0000) GS:ffff88808c2cd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc45c458d20 CR3: 0000000050cdc000 CR4: 0000000000352ef0
Call Trace:
<TASK>
btrfs_bio_csum fs/btrfs/bio.c:601 [inline]
run_one_async_start+0x91/0x130 fs/btrfs/bio.c:635
btrfs_work_helper+0x3a2/0xc50 fs/btrfs/async-thread.c:312
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Struck through repros no longer work on HEAD.