WARNING: ODEBUG bug in free_task
From: syzbot
Date: Tue Oct 09 2018 - 13:14:07 EST
Hello,
syzbot found the following crash on:
HEAD commit: ae16eea39a86 Add linux-next specific files for 20181008
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16a493b9400000
kernel config: https://syzkaller.appspot.com/x/.config?x=42525ce985d1a955
dashboard link: https://syzkaller.appspot.com/bug?extid=71aff6ea121ffefc280f
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14567ae6400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14baa25e400000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+71aff6ea121ffefc280f@xxxxxxxxxxxxxxxxxxxxxxxxx
------------[ cut here ]------------
ODEBUG: free active (active state 1) object type: rcu_head hint:
(null)
WARNING: CPU: 0 PID: 6048 at lib/debugobjects.c:329
debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 6048 Comm: syz-executor022 Not tainted
4.19.0-rc7-next-20181008+ #89
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+0x244/0x3ab lib/dump_stack.c:113
panic+0x238/0x4e7 kernel/panic.c:184
__warn.cold.8+0x163/0x1ba kernel/panic.c:536
report_bug+0x254/0x2d0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:178 [inline]
do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:969
RIP: 0010:debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Code: 41 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 92 00 00 00 48 8b 14 dd
60 02 41 88 4c 89 fe 48 c7 c7 00 f8 40 88 e8 36 2f b4 fd <0f> 0b 83 05 a9
f4 5e 06 01 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffff8801d8c3eda8 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8164d235 RDI: 0000000000000005
RBP: ffff8801d8c3ede8 R08: ffff8801d70aa280 R09: ffffed003b5c3eda
R10: ffffed003b5c3eda R11: ffff8801dae1f6d7 R12: 0000000000000001
R13: ffffffff8939a760 R14: 0000000000000000 R15: ffffffff8840fca0
__debug_check_no_obj_freed lib/debugobjects.c:786 [inline]
debug_check_no_obj_freed+0x3ae/0x58d lib/debugobjects.c:818
kmem_cache_free+0x202/0x290 mm/slab.c:3759
free_task_struct kernel/fork.c:163 [inline]
free_task+0x16e/0x1f0 kernel/fork.c:457
__put_task_struct+0x2e6/0x620 kernel/fork.c:730
put_task_struct include/linux/sched/task.h:96 [inline]
finish_task_switch+0x66c/0x900 kernel/sched/core.c:2715
context_switch kernel/sched/core.c:2834 [inline]
__schedule+0x8d7/0x21d0 kernel/sched/core.c:3480
schedule+0xfe/0x460 kernel/sched/core.c:3524
freezable_schedule include/linux/freezer.h:172 [inline]
futex_wait_queue_me+0x3f9/0x840 kernel/futex.c:2530
futex_wait+0x45c/0xa50 kernel/futex.c:2645
do_futex+0x31a/0x26d0 kernel/futex.c:3528
__do_sys_futex kernel/futex.c:3589 [inline]
__se_sys_futex kernel/futex.c:3557 [inline]
__x64_sys_futex+0x472/0x6a0 kernel/futex.c:3557
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446549
Code: e8 2c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 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 0f 83 2b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3a998f5da8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 0000000000446549
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc38
RBP: 00000000006dbc30 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc3c
R13: 2f646e6162696e69 R14: 666e692f7665642f R15: 00000000006dbd2c
Kernel Offset: disabled
Rebooting in 86400 seconds..
---
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