syzbot


general protection fault in f2fs_in_warm_node_list

Status: premoderation: reported on 2026/05/13 20:58
Reported-by: syzbot+ddd7a7e1049d78014dd9@syzkaller.appspotmail.com
First crash: 1d08h, last: 1d08h
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 general protection fault in f2fs_in_warm_node_list 2 6 12d 40d 0/2 premoderation: reported on 2026/04/04 13:23
android-6-1 general protection fault in f2fs_in_warm_node_list 2 4 8d23h 50d 0/2 premoderation: reported on 2026/03/25 16:06
upstream general protection fault in f2fs_in_warm_node_list f2fs 2 C error 11247 22d 85d 28/29 upstream: reported C repro on 2026/02/18 10:28

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 PID: 13 Comm: ksoftirqd/0 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:NODE_MAPPING fs/f2fs/f2fs.h:2062 [inline]
RIP: 0010:f2fs_in_warm_node_list+0x4b/0x1b0 fs/f2fs/node.c:311
Code: 81 c6 b8 00 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 e3 64 93 ff 4d 8b 36 49 83 c6 30 4c 89 f0 48 c1 e8 03 <42> 80 3c 38 00 74 08 4c 89 f7 e8 c6 64 93 ff 4d 8b 26 4c 8d 73 18
RSP: 0018:ffffc900000d7a08 EFLAGS: 00010006
RAX: 0000000000000006 RBX: ffffea00043cb900 RCX: ffff8881002fa780
RDX: 0000000000000100 RSI: ffffea00043cb900 RDI: ffff88812fa22000
RBP: ffffc900000d7a28 R08: ffff8881f7138ec7 R09: 1ffff1103ee271d8
R10: dffffc0000000000 R11: ffffed103ee271d9 R12: ffff88812fa22690
R13: ffffea00043cb900 R14: 0000000000000030 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000240 CR3: 0000000124183000 CR4: 00000000003506b0
Call Trace:
 <TASK>
 f2fs_write_end_io+0x521/0xb00 fs/f2fs/data.c:372
 bio_endio+0x6d9/0x7e0 block/bio.c:1478
 req_bio_endio block/blk-core.c:272 [inline]
 blk_update_request+0x76a/0x1060 block/blk-core.c:1463
 blk_mq_end_request+0x41/0x80 block/blk-mq.c:581
 blk_flush_complete_seq+0x5de/0xd10 block/blk-flush.c:204
 flush_end_io+0x7dc/0xa50 block/blk-flush.c:261
 __blk_mq_end_request+0x387/0x3e0 block/blk-mq.c:572
 blk_mq_end_request+0x55/0x80 block/blk-mq.c:583
 lo_complete_rq+0x147/0x260 drivers/block/loop.c:530
 blk_complete_reqs block/blk-mq.c:593 [inline]
 blk_done_softirq+0xff/0x140 block/blk-mq.c:598
 handle_softirqs+0x250/0x560 kernel/softirq.c:583
 run_ksoftirqd+0x28/0x40 kernel/softirq.c:959
 smpboot_thread_fn+0x45a/0x8c0 kernel/smpboot.c:164
 kthread+0x411/0x500 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Modules linked in:
---[ end trace 6c2e2adca4fb8d5f ]---
RIP: 0010:NODE_MAPPING fs/f2fs/f2fs.h:2062 [inline]
RIP: 0010:f2fs_in_warm_node_list+0x4b/0x1b0 fs/f2fs/node.c:311
Code: 81 c6 b8 00 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 e3 64 93 ff 4d 8b 36 49 83 c6 30 4c 89 f0 48 c1 e8 03 <42> 80 3c 38 00 74 08 4c 89 f7 e8 c6 64 93 ff 4d 8b 26 4c 8d 73 18
RSP: 0018:ffffc900000d7a08 EFLAGS: 00010006
RAX: 0000000000000006 RBX: ffffea00043cb900 RCX: ffff8881002fa780
RDX: 0000000000000100 RSI: ffffea00043cb900 RDI: ffff88812fa22000
RBP: ffffc900000d7a28 R08: ffff8881f7138ec7 R09: 1ffff1103ee271d8
R10: dffffc0000000000 R11: ffffed103ee271d9 R12: ffff88812fa22690
R13: ffffea00043cb900 R14: 0000000000000030 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000240 CR3: 0000000124183000 CR4: 00000000003506b0
----------------
Code disassembly (best guess):
   0:	81 c6 b8 00 00 00    	add    $0xb8,%esi
   6:	4c 89 f0             	mov    %r14,%rax
   9:	48 c1 e8 03          	shr    $0x3,%rax
   d:	42 80 3c 38 00       	cmpb   $0x0,(%rax,%r15,1)
  12:	74 08                	je     0x1c
  14:	4c 89 f7             	mov    %r14,%rdi
  17:	e8 e3 64 93 ff       	call   0xff9364ff
  1c:	4d 8b 36             	mov    (%r14),%r14
  1f:	49 83 c6 30          	add    $0x30,%r14
  23:	4c 89 f0             	mov    %r14,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 38 00       	cmpb   $0x0,(%rax,%r15,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 f7             	mov    %r14,%rdi
  34:	e8 c6 64 93 ff       	call   0xff9364ff
  39:	4d 8b 26             	mov    (%r14),%r12
  3c:	4c 8d 73 18          	lea    0x18(%rbx),%r14

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/13 20:57 android13-5.15-lts 7f4b368e0410 fec2a7ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in f2fs_in_warm_node_list
* Struck through repros no longer work on HEAD.