WARNING: ODEBUG bug in pppol2tp_release

Status: upstream: reported syz repro on 2021/04/10 09:21
Reported-by: syzbot+5f4eae1a76c7c99bd2ad@syzkaller.appspotmail.com
First crash: 1961d, last: 1394d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Fix bisection attempts (19)
Created Duration User Patch Repo Result
2023/02/03 12:13 0m bisect fix linux-4.14.y error job log
2022/10/29 06:28 24m bisect fix linux-4.14.y OK (0) job log log
2022/09/10 09:50 21m bisect fix linux-4.14.y OK (0) job log log
2022/08/11 09:20 30m bisect fix linux-4.14.y OK (0) job log log
2022/07/12 08:54 20m bisect fix linux-4.14.y OK (0) job log log
2022/06/12 08:33 21m bisect fix linux-4.14.y OK (0) job log log
2022/05/13 08:09 24m bisect fix linux-4.14.y OK (0) job log log
2022/04/13 07:44 24m bisect fix linux-4.14.y OK (0) job log log
2022/03/14 03:45 21m bisect fix linux-4.14.y OK (0) job log log
2022/02/11 15:23 31m bisect fix linux-4.14.y OK (0) job log log
2022/01/12 14:31 24m bisect fix linux-4.14.y OK (0) job log log
2021/12/13 14:04 26m bisect fix linux-4.14.y OK (0) job log log
2021/11/13 11:07 23m bisect fix linux-4.14.y OK (0) job log log
2021/10/14 10:40 26m bisect fix linux-4.14.y OK (0) job log log
2021/09/14 10:14 25m bisect fix linux-4.14.y OK (0) job log log
2021/08/15 09:49 25m bisect fix linux-4.14.y OK (0) job log log
2021/07/16 09:21 27m bisect fix linux-4.14.y OK (0) job log log
2021/06/16 08:57 23m bisect fix linux-4.14.y OK (0) job log log
2021/05/10 10:14 28m bisect fix linux-4.14.y OK (0) job log log

Sample crash report:
batman_adv: batadv0: Interface activated: batadv_slave_1
IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready
ODEBUG: activate active (active state 1) object type: rcu_head hint:           (null)
------------[ cut here ]------------
WARNING: CPU: 1 PID: 9606 at lib/debugobjects.c:287 debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 9606 Comm: syz-executor.5 Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 panic+0x1f9/0x42d kernel/panic.c:183
 __warn.cold+0x20/0x44 kernel/panic.c:547
 report_bug+0x208/0x250 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
RSP: 0018:ffff88808ddc79c0 EFLAGS: 00010086
RAX: 0000000000000055 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff878bbbc0 RDI: ffffed1011bb8f2e
RBP: ffffffff878b0d40 R08: 0000000000000055 R09: 0000000000000000
R10: 0000000000000000 R11: ffff888091d26200 R12: 0000000000000000
R13: 0000000000000001 R14: 1ffff11011bb8f41 R15: ffff88808ddc7a88
 debug_object_activate+0x2f3/0x490 lib/debugobjects.c:446
 debug_rcu_head_queue kernel/rcu/rcu.h:152 [inline]
 __call_rcu.constprop.0+0x31/0x7d0 kernel/rcu/tree.c:3050
 pppol2tp_release+0x263/0x3b0 net/l2tp/l2tp_ppp.c:515
 __sock_release+0xcd/0x2b0 net/socket.c:602
 sock_close+0x15/0x20 net/socket.c:1139
 __fput+0x25f/0x7a0 fs/file_table.c:210
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 get_signal+0x18a3/0x1ca0 kernel/signal.c:2234
 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792
 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4665d9
RSP: 002b:00007f9a0e5c0188 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: 0000000000000000 RBX: 000000000056bf60 RCX: 00000000004665d9
RDX: 0000000000000032 RSI: 0000000020000140 RDI: 0000000000000005
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffd318c755f R14: 00007f9a0e5c0300 R15: 0000000000022000

======================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/17 08:32 linux-4.14.y 7d7d1c0ab3eb f54a5c09 .config console log report syz ci2-linux-4-14 WARNING: ODEBUG bug in pppol2tp_release
2021/04/10 10:14 linux-4.14.y 0cc244011f40 6a81331a .config console log report syz ci2-linux-4-14 WARNING: ODEBUG bug in pppol2tp_release
2021/04/10 09:20 linux-4.14.y 0cc244011f40 6a81331a .config console log report info ci2-linux-4-14 WARNING: ODEBUG bug in pppol2tp_release
* Struck through repros no longer work on HEAD.