syzbot


BUG: bad unlock balance in ipmr_mfc_seq_stop

Status: fixed on 2018/02/20 22:33
Fix commit: ip6mr: fix stale iterator
First crash: 2275d, last: 2218d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 BUG: bad unlock balance in ipmr_mfc_seq_stop C 7493 2208d 2286d 2/3 fixed on 2018/02/14 02:00

Sample crash report:
=====================================
[ BUG: bad unlock balance detected! ]
4.4.114-g4e74e98 #5 Not tainted
-------------------------------------
syz-executor7/9485 is trying to release lock (mrt_lock) at:
[<ffffffff833c7904>] ipmr_mfc_seq_stop+0xe4/0x140 net/ipv6/ip6mr.c:553
but there are no more locks to release!

other info that might help us debug this:
2 locks held by syz-executor7/9485:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8157ac1f>] __fdget_pos+0x9f/0xc0 fs/file.c:780
 #1:  (&p->lock){+.+.+.}, at: [<ffffffff8158d6cd>] seq_read+0xdd/0x1270 fs/seq_file.c:178

stack backtrace:
CPU: 1 PID: 9485 Comm: syz-executor7 Not tainted 4.4.114-g4e74e98 #5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 f1073ee38eeb3f05 ffff8800aa57f920 ffffffff81d03d2d
 ffffffff84771c98 ffff8801d96f4800 ffffffff833c7904 ffffffff84771c98
 ffff8801d96f50a8 ffff8800aa57f950 ffffffff81233354 dffffc0000000000
Call Trace:
 [<ffffffff81d03d2d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d03d2d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff81233354>] print_unlock_imbalance_bug+0x174/0x1a0 kernel/locking/lockdep.c:3266
 [<ffffffff8123e1ea>] __lock_release kernel/locking/lockdep.c:3408 [inline]
 [<ffffffff8123e1ea>] lock_release+0x72a/0xc10 kernel/locking/lockdep.c:3611
 [<ffffffff83773bda>] __raw_read_unlock include/linux/rwlock_api_smp.h:225 [inline]
 [<ffffffff83773bda>] _raw_read_unlock+0x1a/0x50 kernel/locking/spinlock.c:255
 [<ffffffff833c7904>] ipmr_mfc_seq_stop+0xe4/0x140 net/ipv6/ip6mr.c:553
 [<ffffffff8158e070>] seq_read+0xa80/0x1270 fs/seq_file.c:283
 [<ffffffff81665d1f>] proc_reg_read+0xef/0x170 fs/proc/inode.c:202
 [<ffffffff8151d891>] do_loop_readv_writev+0x141/0x1e0 fs/read_write.c:680
 [<ffffffff8151fbed>] do_readv_writev+0x5dd/0x6e0 fs/read_write.c:810
 [<ffffffff8151fd68>] vfs_readv+0x78/0xb0 fs/read_write.c:834
 [<ffffffff81522099>] SYSC_readv fs/read_write.c:860 [inline]
 [<ffffffff81522099>] SyS_readv+0xd9/0x240 fs/read_write.c:852
 [<ffffffff837742df>] entry_SYSCALL_64_fastpath+0x1c/0x98

Crashes (98):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/02/03 17:26 https://android.googlesource.com/kernel/common android-4.4 4e74e983ab6e 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/03 10:13 https://android.googlesource.com/kernel/common android-4.4 4e74e983ab6e 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/03 07:44 https://android.googlesource.com/kernel/common android-4.4 4e74e983ab6e 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/03 07:10 https://android.googlesource.com/kernel/common android-4.4 4e74e983ab6e 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/03 05:00 https://android.googlesource.com/kernel/common android-4.4 4e74e983ab6e 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/03 04:01 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/03 02:48 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/03 01:09 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/02 20:14 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/02 19:25 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/02 16:32 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 632a8c2c .config console log report ci-android-44-kasan-gce
2018/02/02 13:32 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 826b35d6 .config console log report ci-android-44-kasan-gce
2018/02/02 00:06 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 67bd3383 .config console log report ci-android-44-kasan-gce
2018/02/02 00:00 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 67bd3383 .config console log report ci-android-44-kasan-gce
2018/02/01 23:27 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 67bd3383 .config console log report ci-android-44-kasan-gce
2018/02/01 22:56 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 67bd3383 .config console log report ci-android-44-kasan-gce
2018/02/01 21:41 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 67bd3383 .config console log report ci-android-44-kasan-gce
2018/02/01 21:40 https://android.googlesource.com/kernel/common android-4.4 a81d32264721 67bd3383 .config console log report ci-android-44-kasan-gce
2018/01/30 18:05 https://android.googlesource.com/kernel/common android-4.4 962d1f3fe2f4 a899be78 .config console log report ci-android-44-kasan-gce
2018/01/30 06:44 https://android.googlesource.com/kernel/common android-4.4 962d1f3fe2f4 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/29 08:14 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/29 06:04 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/29 05:02 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/29 04:58 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/29 02:34 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/29 00:00 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/28 23:07 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/28 22:03 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/28 19:53 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/28 18:26 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/28 17:47 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/28 16:27 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/28 14:17 https://android.googlesource.com/kernel/common android-4.4 202e079275c6 08d47756 .config console log report ci-android-44-kasan-gce
2018/01/15 08:05 https://android.googlesource.com/kernel/common android-4.4 1849cd3d301d 66d492a6 .config console log report ci-android-44-kasan-gce-386
2018/01/15 02:57 https://android.googlesource.com/kernel/common android-4.4 1849cd3d301d 66d492a6 .config console log report ci-android-44-kasan-gce
2018/01/14 23:27 https://android.googlesource.com/kernel/common android-4.4 1849cd3d301d 66d492a6 .config console log report ci-android-44-kasan-gce-386
2018/01/14 10:17 https://android.googlesource.com/kernel/common android-4.4 1849cd3d301d c9e7aeae .config console log report ci-android-44-kasan-gce
2018/01/14 01:57 https://android.googlesource.com/kernel/common android-4.4 7902639f8133 c9e7aeae .config console log report ci-android-44-kasan-gce
2018/01/13 20:06 https://android.googlesource.com/kernel/common android-4.4 7902639f8133 c9e7aeae .config console log report ci-android-44-kasan-gce-386
2018/01/13 14:23 https://android.googlesource.com/kernel/common android-4.4 7902639f8133 c9e7aeae .config console log report ci-android-44-kasan-gce-386
2018/01/03 10:46 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce-386
2018/01/03 09:58 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce
2018/01/03 09:06 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce-386
2018/01/03 00:21 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce
2018/01/02 22:11 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce-386
2018/01/02 17:47 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce
2018/01/02 17:09 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce
2018/01/02 16:30 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce-386
2018/01/02 15:52 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce-386
2018/01/02 02:52 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce-386
2018/01/01 21:58 https://android.googlesource.com/kernel/common android-4.4 610c835673f3 00193447 .config console log report syz C ci-android-44-kasan-gce
2017/12/09 19:48 https://android.googlesource.com/kernel/common android-4.4 ed884ebd80a9 5ad0ce95 .config console log report syz C ci-android-44-kasan-gce
* Struck through repros no longer work on HEAD.