WARNING: locking bug in loop_control_ioctl
From: syzbot
Date: Fri Nov 09 2018 - 14:48:07 EST
Hello,
syzbot found the following crash on:
HEAD commit: 442b8cea2477 Add linux-next specific files for 20181109
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=14790f7b400000
kernel config: https://syzkaller.appspot.com/x/.config?x=66046c6bfaf1f24d
dashboard link: https://syzkaller.appspot.com/bug?extid=c0138741c2290fc5e63f
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15ef394d400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=111cfb83400000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c0138741c2290fc5e63f@xxxxxxxxxxxxxxxxxxxxxxxxx
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(depth <= 0)
WARNING: CPU: 1 PID: 5795 at kernel/locking/lockdep.c:3595 __lock_release
kernel/locking/lockdep.c:3595 [inline]
WARNING: CPU: 1 PID: 5795 at kernel/locking/lockdep.c:3595
lock_release+0x740/0xa10 kernel/locking/lockdep.c:3863
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 5795 Comm: syz-executor569 Not tainted
4.20.0-rc1-next-20181109+ #109
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+0x244/0x39d lib/dump_stack.c:113
panic+0x2ad/0x55c kernel/panic.c:188
__warn.cold.8+0x20/0x45 kernel/panic.c:540
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:__lock_release kernel/locking/lockdep.c:3595 [inline]
RIP: 0010:lock_release+0x740/0xa10 kernel/locking/lockdep.c:3863
Code: 03 38 d0 7c 08 84 d2 0f 85 da 02 00 00 8b 35 a7 82 b3 08 85 f6 75 15
48 c7 c6 20 66 2b 88 48 c7 c7 c0 33 2b 88 e8 10 36 e7 ff <0f> 0b 48 8b 95
e8 fe ff ff 4c 89 f7 48 8b b5 f0 fe ff ff e8 e8 58
RSP: 0018:ffff8801b9867868 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 1ffff1003730cf12 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8165ba15 RDI: 0000000000000006
RBP: ffff8801b9867998 R08: ffff8801d24940c0 R09: fffffbfff12b2254
R10: fffffbfff12b2254 R11: ffffffff895912a3 R12: ffffffff8b0e17a0
R13: ffff8801b9867970 R14: ffff8801d24940c0 R15: ffff8801b98678b0
__mutex_unlock_slowpath+0x102/0x8c0 kernel/locking/mutex.c:1197
mutex_unlock+0xd/0x10 kernel/locking/mutex.c:713
loop_control_ioctl+0xf5/0x4e0 drivers/block/loop.c:2095
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696
ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x447009
Code: e8 0c b4 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 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fba6d10bda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006e19e8 RCX: 0000000000447009
RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000003
RBP: 00000000006e19e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e19ec
R13: 6f72746e6f632d70 R14: 6f6f6c2f7665642f R15: 00000000006e19e0
Kernel Offset: disabled
Rebooting in 86400 seconds..
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