On Fri, Aug 28, 2020 at 5:08 PM syzbot <syzbot+fbd7ba7207767ed15165@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: d012a719 Linux 5.9-rc2 > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=15e9e90e900000 > kernel config: https://syzkaller.appspot.com/x/.config?x=978db74cb30aa994 > dashboard link: https://syzkaller.appspot.com/bug?extid=fbd7ba7207767ed15165 > compiler: gcc (GCC) 10.1.0-syz 20200507 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12f81666900000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15abb10e900000 > > The issue was bisected to: > > commit a9ed4a6560b8562b7e2e2bed9527e88001f7b682 > Author: Marc Zyngier <maz@xxxxxxxxxx> > Date: Wed Aug 19 16:12:17 2020 +0000 > > epoll: Keep a reference on files added to the check list > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=130823a9900000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=108823a9900000 > console output: https://syzkaller.appspot.com/x/log.txt?x=170823a9900000 #syz fix: fix regression in "epoll: Keep a reference on files added to the check list" > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+fbd7ba7207767ed15165@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: a9ed4a6560b8 ("epoll: Keep a reference on files added to the check list") > > ------------[ cut here ]------------ > ODEBUG: free active (active state 1) object type: rcu_head hint: 0x0 > WARNING: CPU: 1 PID: 10170 at lib/debugobjects.c:485 debug_print_object+0x160/0x250 lib/debugobjects.c:485 > Kernel panic - not syncing: panic_on_warn set ... > CPU: 1 PID: 10170 Comm: syz-executor403 Not tainted 5.9.0-rc2-syzkaller #0 > 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+0x18f/0x20d lib/dump_stack.c:118 > panic+0x2e3/0x75c kernel/panic.c:231 > __warn.cold+0x20/0x4a kernel/panic.c:600 > report_bug+0x1bd/0x210 lib/bug.c:198 > handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234 > exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254 > asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536 > RIP: 0010:debug_print_object+0x160/0x250 lib/debugobjects.c:485 > Code: dd e0 26 94 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 bf 00 00 00 48 8b 14 dd e0 26 94 88 48 c7 c7 40 1c 94 88 e8 82 3b a6 fd <0f> 0b 83 05 83 54 13 07 01 48 83 c4 20 5b 5d 41 5c 41 5d c3 48 89 > RSP: 0018:ffffc9000dabfdd0 EFLAGS: 00010082 > RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 > RDX: ffff888093ada540 RSI: ffffffff815dafc7 RDI: fffff52001b57fac > RBP: 0000000000000001 R08: 0000000000000001 R09: ffff8880ae720f8b > R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89bd6780 > R13: 0000000000000000 R14: dead000000000100 R15: dffffc0000000000 > __debug_check_no_obj_freed lib/debugobjects.c:967 [inline] > debug_check_no_obj_freed+0x301/0x41c lib/debugobjects.c:998 > kmem_cache_free.part.0+0x16d/0x1f0 mm/slab.c:3692 > task_work_run+0xdd/0x190 kernel/task_work.c:141 > tracehook_notify_resume include/linux/tracehook.h:188 [inline] > exit_to_user_mode_loop kernel/entry/common.c:140 [inline] > exit_to_user_mode_prepare+0x195/0x1c0 kernel/entry/common.c:167 > syscall_exit_to_user_mode+0x59/0x2b0 kernel/entry/common.c:242 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > RIP: 0033:0x447849 > Code: e8 9c e6 ff ff 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 bb 04 fc ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007f37799a7db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9 > RAX: 0000000000000000 RBX: 00000000006ddc68 RCX: 0000000000447849 > RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000004 > RBP: 00000000006ddc60 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000020000000 R11: 0000000000000246 R12: 00000000006ddc6c > R13: 00007ffcdbf7f6bf R14: 00007f37799a89c0 R15: 0000000000000000 > Shutting down cpus with NMI > Kernel Offset: disabled > Rebooting in 86400 seconds.. > > > --- > This report 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 issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/0000000000006226c805adf16cb8%40google.com.
