syzbot


kernel BUG in f2fs_put_super (4)

Status: upstream: reported on 2025/12/29 12:52
Subsystems: f2fs
[Documentation on labels]
Reported-by: syzbot+c0a575209250b34549be@syzkaller.appspotmail.com
First crash: 6d08h, last: 6d08h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [f2fs?] kernel BUG in f2fs_put_super (4) 0 (1) 2025/12/29 12:52
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG in f2fs_put_super f2fs -1 2 817d 847d 25/29 fixed on 2023/12/21 03:45
upstream kernel BUG in f2fs_put_super (3) f2fs -1 1 267d 263d 0/29 auto-obsoleted due to no activity on 2025/07/17 03:15
upstream kernel BUG in f2fs_put_super (2) f2fs -1 1 376d 372d 0/29 auto-obsoleted due to no activity on 2025/03/29 22:05

Sample crash report:
F2FS-fs (loop5): detect filesystem reference count leak during umount, type: 2, count: -1
------------[ cut here ]------------
kernel BUG at fs/f2fs/super.c:2008!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 5980 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:f2fs_put_super+0x1165/0x1170 fs/f2fs/super.c:2008
Code: fd 41 bf 0c 00 00 00 48 89 df 44 89 fe e8 23 3f 00 00 48 89 df 31 f6 48 c7 c2 00 da 33 8b 44 89 f9 49 89 c0 e8 7c 70 fd ff 90 <0f> 0b 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900056579a0 EFLAGS: 00010246
RAX: b18dcddbdfba5600 RBX: ffff88805e754000 RCX: b18dcddbdfba5600
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90005657b98 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000acaebd R12: ffff88805e754000
R13: dffffc0000000000 R14: 00000000ffffffff R15: 0000000000000002
FS:  000055556c854500(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fad42ebb000 CR3: 0000000029164000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 generic_shutdown_super+0x135/0x2c0 fs/super.c:643
 kill_block_super+0x44/0x90 fs/super.c:1722
 kill_f2fs_super+0x39f/0x6c0 fs/f2fs/super.c:5454
 deactivate_locked_super+0xbc/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318
 task_work_run+0x1d4/0x260 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
 exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f142cea0a77
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc21036858 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f142cf23d7d RCX: 00007f142cea0a77
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc21036910
RBP: 00007ffc21036910 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc210379a0
R13: 00007f142cf23d7d R14: 000000000002714a R15: 00007ffc210379e0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:f2fs_put_super+0x1165/0x1170 fs/f2fs/super.c:2008
Code: fd 41 bf 0c 00 00 00 48 89 df 44 89 fe e8 23 3f 00 00 48 89 df 31 f6 48 c7 c2 00 da 33 8b 44 89 f9 49 89 c0 e8 7c 70 fd ff 90 <0f> 0b 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900056579a0 EFLAGS: 00010246
RAX: b18dcddbdfba5600 RBX: ffff88805e754000 RCX: b18dcddbdfba5600
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90005657b98 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000acaebd R12: ffff88805e754000
R13: dffffc0000000000 R14: 00000000ffffffff R15: 0000000000000002
FS:  000055556c854500(0000) GS:ffff888126def000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fab7d2756c0 CR3: 0000000029164000 CR4: 00000000003526f0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/25 12:43 upstream ccd1cdca5cd4 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs kernel BUG in f2fs_put_super
* Struck through repros no longer work on HEAD.