On Fri, Dec 01, 2017 at 03:30:01AM -0800, syzbot wrote: > Hello, > > syzkaller hit the following crash on > df8ba95c572a187ed2aa7403e97a7a7f58c01f00 > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > > Unfortunately, I don't have any reproducer for this bug yet. > > > > ===================================== > WARNING: bad unlock balance detected! > 4.15.0-rc1+ #202 Not tainted > ------------------------------------- > syz-executor4/28722 is trying to release lock (mrt_lock) at: > [<00000000c358606b>] ipmr_mfc_seq_stop+0xe1/0x130 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-executor4/28722: > #0: (sb_writers#6){.+.+}, at: [<000000003332d098>] file_start_write > include/linux/fs.h:2715 [inline] > #0: (sb_writers#6){.+.+}, at: [<000000003332d098>] do_sendfile+0xaec/0xe90 > fs/read_write.c:1412 > #1: (&p->lock){+.+.}, at: [<000000001572c807>] seq_read+0xd5/0x13d0 > fs/seq_file.c:165 > > stack backtrace: > CPU: 0 PID: 28722 Comm: syz-executor4 Not tainted 4.15.0-rc1+ #202 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:17 [inline] > dump_stack+0x194/0x257 lib/dump_stack.c:53 > print_unlock_imbalance_bug+0x12f/0x140 kernel/locking/lockdep.c:3561 > __lock_release kernel/locking/lockdep.c:3775 [inline] > lock_release+0x5f9/0xda0 kernel/locking/lockdep.c:4023 > __raw_read_unlock include/linux/rwlock_api_smp.h:225 [inline] > _raw_read_unlock+0x1a/0x30 kernel/locking/spinlock.c:255 > ipmr_mfc_seq_stop+0xe1/0x130 net/ipv6/ip6mr.c:553 > seq_read+0xc42/0x13d0 fs/seq_file.c:277 > proc_reg_read+0xef/0x170 fs/proc/inode.c:217 > do_loop_readv_writev fs/read_write.c:673 [inline] > do_iter_read+0x3db/0x5b0 fs/read_write.c:897 > vfs_readv+0x121/0x1c0 fs/read_write.c:959 > kernel_readv fs/splice.c:361 [inline] > default_file_splice_read+0x508/0xae0 fs/splice.c:416 > do_splice_to+0x110/0x170 fs/splice.c:880 > splice_direct_to_actor+0x242/0x820 fs/splice.c:952 > do_splice_direct+0x2a7/0x3d0 fs/splice.c:1061 > do_sendfile+0x5d5/0xe90 fs/read_write.c:1413 > SYSC_sendfile64 fs/read_write.c:1468 [inline] > SyS_sendfile64+0xbd/0x160 fs/read_write.c:1460 > entry_SYSCALL_64_fastpath+0x1f/0x96 > RIP: 0033:0x4529d9 > RSP: 002b:00007f225b206c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000028 > RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 00000000004529d9 > RDX: 0000000020360ff8 RSI: 0000000000000014 RDI: 0000000000000014 > RBP: 0000000000000561 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000008 R11: 0000000000000212 R12: 00000000006f51b8 > R13: 00000000ffffffff R14: 00007f225b2076d4 R15: 0000000000000000 > WARNING: CPU: 0 PID: 28722 at lib/usercopy.c:26 _copy_to_user+0xb5/0xc0 > lib/usercopy.c:26 > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkal...@googlegroups.com. > Please credit me with: Reported-by: syzbot <syzkal...@googlegroups.com> > > syzbot will keep track of this bug report. > Once a fix for this bug is committed, please reply to this email with: > #syz fix: exact-commit-title > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid
Duplicate of "WARNING: bad unlock balance in ipmr_mfc_seq_stop" which syzbot is detecting under that crash signature now, so just invalidating this one: #syz invalid