syzbot


WARNING: ODEBUG bug in exit_to_usermode_loop

Status: fixed on 2020/10/07 06:25
Reported-by: syzbot+55c67ce74d4586507d2f@syzkaller.appspotmail.com
Fix commit: dff6a2c2828b nvmet-fc: Fix a missed _irqsave version of spin_lock in 'nvmet_fc_fod_op_done()'
First crash: 667d, last: 665d

Fix bisection: fixed by (bisect log) :
commit dff6a2c2828bce13f32c62029def97195f8830f6
Author: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Fri Aug 21 07:58:19 2020 +0000

  nvmet-fc: Fix a missed _irqsave version of spin_lock in 'nvmet_fc_fod_op_done()'

similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 WARNING: ODEBUG bug in exit_to_usermode_loop syz done 2 666d 668d 1/1 fixed on 2020/10/05 13:19

Sample crash report:
------------[ cut here ]------------
ODEBUG: free active (active state 1) object type: rcu_head hint:           (null)
WARNING: CPU: 1 PID: 19295 at lib/debugobjects.c:325 debug_print_object+0x160/0x250 lib/debugobjects.c:325
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 19295 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:ffff88808f7bfd98 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8154d001 RDI: ffffed1011ef7fa5
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000005 R11: ffffffff8ad3805b R12: ffffffff88d93700
R13: 0000000000000000 R14: ffff88808f7697a8 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
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
 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:00007fde4e5a9c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9
RAX: 0000000000000000 RBX: 0000000000002ac0 RCX: 000000000045d5b9
RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000005
RBP: 000000000118d028 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000100 R11: 0000000000000246 R12: 000000000118cfec
R13: 00007ffd2488239f R14: 00007fde4e5aa9c0 R15: 000000000118cfec

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

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2020/09/06 04:12 linux-4.19.y c37da90efff5 abf9ba4f .config log report syz
ci2-linux-4-19 2020/09/04 04:19 linux-4.19.y c37da90efff5 abf9ba4f .config log report syz