syzbot


WARNING: ODEBUG bug in get_signal

Status: fixed on 2020/10/07 06:25
Reported-by: syzbot+c5444152db81146ebc87@syzkaller.appspotmail.com
Fix commit: 37d933e8b41b fix regression in "epoll: Keep a reference on files added to the check list"
First crash: 1362d, last: 1352d
Fix bisection: fixed by (bisect log) :
commit 37d933e8b41b83bb8278815e366aec5a542b7e31
Author: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed Sep 2 15:30:48 2020 +0000

  fix regression in "epoll: Keep a reference on files added to the check list"

  
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING: ODEBUG bug in get_signal kernel syz done unreliable 9 1354d 1362d 0/26 auto-obsoleted due to no activity on 2022/09/23 03:01
linux-4.14 WARNING: ODEBUG bug in get_signal 1 1353d 1353d 0/1 auto-closed as invalid on 2021/01/03 14:38

Sample crash report:
Bluetooth: hci0: command 0x0419 tx timeout
Bluetooth: hci1: command 0x0419 tx timeout
Bluetooth: hci4: command 0x0419 tx timeout
------------[ cut here ]------------
ODEBUG: free active (active state 1) object type: rcu_head hint:           (null)
WARNING: CPU: 0 PID: 8069 at lib/debugobjects.c:325 debug_print_object+0x160/0x250 lib/debugobjects.c:325
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 8069 Comm: syz-executor.2 Not tainted 4.19.143-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
 panic+0x26a/0x50e kernel/panic.c:186
 __warn.cold+0x20/0x61 kernel/panic.c:541
 report_bug+0x262/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x1d7/0x310 arch/x86/kernel/traps.c:296
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:debug_print_object+0x160/0x250 lib/debugobjects.c:325
Code: dd 40 1b cb 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 bf 00 00 00 48 8b 14 dd 40 1b cb 87 48 c7 c7 c0 10 cb 87 e8 bb f0 dc fd <0f> 0b 83 05 43 01 4e 06 01 48 83 c4 20 5b 5d 41 5c 41 5d c3 48 89
RSP: 0018:ffff88808cf7fb08 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8154d001 RDI: ffffed10119eff53
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000005 R11: ffffffff8ad3801b R12: ffffffff88d93700
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
 __debug_check_no_obj_freed lib/debugobjects.c:785 [inline]
 debug_check_no_obj_freed+0x271/0x482 lib/debugobjects.c:817
 kmem_cache_free+0xff/0x260 mm/slab.c:3764
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 get_signal+0x1b64/0x1f70 kernel/signal.c:2399
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45d5b9
Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007febdd4dac78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9
RAX: 0000000000000000 RBX: 0000000000002ac0 RCX: 000000000045d5b9
RDX: 0000000000000005 RSI: 0000000000000001 RDI: 0000000000000006
RBP: 000000000118cf88 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000340 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffc0aa6fcdf R14: 00007febdd4db9c0 R15: 000000000118cf4c

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

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/09/05 22:03 linux-4.19.y c37da90efff5 abf9ba4f .config console log report syz ci2-linux-4-19
2020/08/27 09:13 linux-4.19.y f6d5cb9e2c06 816e0689 .config console log report syz ci2-linux-4-19
2020/09/06 02:03 linux-4.19.y c37da90efff5 abf9ba4f .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.