syzbot
WARNING: ODEBUG bug in generic_shutdown_super (2)
Status:
moderation: reported on 2026/09/18 13:29
Subsystems:
fs
Labels:
prio:high
[Documentation on labels]
Reported-by: syzbot+0488fa02256dd321f4ec@syzkaller.appspotmail.com
First crash: 50d, last: 30d
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Last patch testing requests (1)
Sample crash report:
loop0: detected capacity change from 0 to 32768
gfs2: fsid=syz:syz: Trying to join cluster "lock_nolock", "syz:syz"
gfs2: fsid=syz:syz: Now mounting FS (format 1801)...
gfs2: fsid=syz:syz.0: journal 0 mapped with 3 extents in 0ms
gfs2: fsid=syz:syz.0: first mount done, others may mount
gfs2: fsid=syz:syz.0: found 1 quota changes
loop0: detected capacity change from 32768 to 0
gfs2: fsid=syz:syz.0: Error -5 writing to journal, jid=0
CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 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
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
gfs2_withdraw+0xc3/0x1b0 fs/gfs2/util.c:249
gfs2_end_log_write+0xcd/0x6c0 fs/gfs2/lops.c:212
gfs2_log_submit_write+0x7e/0xb0 fs/gfs2/lops.c:245
gfs2_write_log_header+0x775/0x950 fs/gfs2/log.c:894
log_write_header+0x3d4/0x5f0 fs/gfs2/log.c:918
gfs2_log_shutdown+0xbb/0x2b0 fs/gfs2/log.c:1325
__gfs2_log_flush+0x16f9/0x1d90 fs/gfs2/log.c:1174
gfs2_log_flush+0x34/0x50 fs/gfs2/log.c:1216
gfs2_make_fs_ro+0x185/0x320 fs/gfs2/super.c:561
gfs2_put_super+0x235/0x870 fs/gfs2/super.c:603
generic_shutdown_super+0x13d/0x2d0 fs/super.c:751
kill_block_super+0x44/0xa0 fs/super.c:1903
deactivate_locked_super+0xbe/0x110 fs/super.c:586
cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317
task_work_run+0x1d9/0x270 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:70 [inline]
exit_to_user_mode_loop+0x204/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9eeb79e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9eec638fe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f9eeba25fa0 RCX: 00007f9eeb79e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000002c0
RBP: 00007f9eeb83506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9eeba26038 R14: 00007f9eeba25fa0 R15: 00007fff5641d318
</TASK>
gfs2: fsid=syz:syz.0: about to withdraw this file system
------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff88801248c598 object type: work_struct hint: gfs2_withdraw_func+0x0/0x440 fs/gfs2/util.c:-1
WARNING: lib/debugobjects.c:632 at debug_print_object+0xec/0x230 lib/debugobjects.c:629, CPU#0: syz.0.0/5327
Modules linked in:
CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 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
RIP: 0010:debug_print_object+0x18a/0x230 lib/debugobjects.c:629
Code: f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 5d bb 4c fd 4d 8b 0f 4c 89 ef 48 8b 74 24 08 48 89 ea 44 89 e1 4d 89 f0 ff 34 24 <67> 48 0f b9 3a 48 83 c4 08 ff 05 53 a5 8d 0b 48 83 c4 10 5b 41 5c
RSP: 0000:ffffc9000db8fbb0 EFLAGS: 00010246
RAX: 1ffffffff1816f44 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffffffff8c6dd940 RSI: ffffffff8c6dd3c0 RDI: ffffffff9085b190
RBP: ffffffff8c6dd940 R08: ffff88801248c598 R09: ffffffff8c0b8c40
R10: dffffc0000000000 R11: ffffffff818f8860 R12: 0000000000000000
R13: ffffffff9085b190 R14: ffff88801248c598 R15: ffffffff8c0b7a20
FS: 00007f9eec6396c0(0000) GS:ffff88808c2bb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbee0f6b2b0 CR3: 0000000043959000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__debug_check_no_obj_freed lib/debugobjects.c:1171 [inline]
debug_check_no_obj_freed+0x2e3/0x450 lib/debugobjects.c:1201
slab_free_hook mm/slub.c:2679 [inline]
slab_free mm/slub.c:6509 [inline]
kfree+0x13e/0x650 mm/slub.c:6802
generic_shutdown_super+0x13d/0x2d0 fs/super.c:751
kill_block_super+0x44/0xa0 fs/super.c:1903
deactivate_locked_super+0xbe/0x110 fs/super.c:586
cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317
task_work_run+0x1d9/0x270 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:70 [inline]
exit_to_user_mode_loop+0x204/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9eeb79e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9eec638fe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f9eeba25fa0 RCX: 00007f9eeb79e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000002c0
RBP: 00007f9eeb83506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9eeba26038 R14: 00007f9eeba25fa0 R15: 00007fff5641d318
</TASK>
----------------
Code disassembly (best guess):
0: f8 clc
1: 48 c1 e8 03 shr $0x3,%rax
5: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1)
9: 74 08 je 0x13
b: 4c 89 ff mov %r15,%rdi
e: e8 5d bb 4c fd call 0xfd4cbb70
13: 4d 8b 0f mov (%r15),%r9
16: 4c 89 ef mov %r13,%rdi
19: 48 8b 74 24 08 mov 0x8(%rsp),%rsi
1e: 48 89 ea mov %rbp,%rdx
21: 44 89 e1 mov %r12d,%ecx
24: 4d 89 f0 mov %r14,%r8
27: ff 34 24 push (%rsp)
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 48 83 c4 08 add $0x8,%rsp
33: ff 05 53 a5 8d 0b incl 0xb8da553(%rip) # 0xb8da58c
39: 48 83 c4 10 add $0x10,%rsp
3d: 5b pop %rbx
3e: 41 5c pop %r12
Struck through repros no longer work on HEAD.