Hello, syzbot found the following crash on: HEAD commit: 8f3d9f35 Linux 5.7-rc1 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1182b24fe00000 kernel config: https://syzkaller.appspot.com/x/.config?x=11f10cc27c63cade dashboard link: https://syzkaller.appspot.com/bug?extid=2e9900a1e1b3c9c96a77 compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+2e9900a1e1b3c9c96a77@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 10817 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 10817 Comm: kworker/0:7 Not tainted 5.7.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events do_enable_set Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1e9/0x30e lib/dump_stack.c:118 panic+0x264/0x7a0 kernel/panic.c:221 __warn+0x209/0x210 kernel/panic.c:582 report_bug+0x1ac/0x2d0 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:175 [inline] do_error_trap+0xca/0x1c0 arch/x86/kernel/traps.c:267 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 Code: c7 9a a9 f2 88 31 c0 e8 a3 fb ac fd 0f 0b eb 85 e8 5a e7 da fd c6 05 10 48 cf 05 01 48 c7 c7 c6 a9 f2 88 31 c0 e8 85 fb ac fd <0f> 0b e9 64 ff ff ff e8 39 e7 da fd c6 05 f0 47 cf 05 01 48 c7 c7 RSP: 0000:ffffc900016d7c48 EFLAGS: 00010246 RAX: 8e9964d9ee901300 RBX: 0000000000000003 RCX: ffff888089a0e5c0 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: 0000000000000003 R08: ffffffff815cbca9 R09: ffffed1015d06660 R10: ffffed1015d06660 R11: 0000000000000000 R12: ffffffff895f43c8 R13: dffffc0000000000 R14: ffff88809365b018 R15: ffff8880ae83b400 do_enable_set+0x63a/0x8d0 net/bluetooth/6lowpan.c:1075 process_one_work+0x76e/0xfd0 kernel/workqueue.c:2268 worker_thread+0xa7f/0x1450 kernel/workqueue.c:2414 kthread+0x353/0x380 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Kernel Offset: disabled Rebooting in 86400 seconds.. --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
