On 10/10/2018 09:57, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 570b7bdeaf18 Add linux-next specific files for 20181009 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=15f27959400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=9b5a60e1381390c4 > dashboard link: > https://syzkaller.appspot.com/bug?extid=e593df3bb8f541d497b9 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > > 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+e593df3bb8f541d49...@syzkaller.appspotmail.com > > BUG: unable to handle kernel paging request at ffffc90001b356b0 > PGD 1da948067 P4D 1da948067 PUD 1da949067 PMD 1ce844067 PTE 0 > Oops: 0000 [#1] PREEMPT SMP KASAN > CPU: 1 PID: 11542 Comm: syz-executor2 Not tainted > 4.19.0-rc7-next-20181009+ #90 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > kobject: 'queues' (00000000da0a0759): kobject_uevent_env > RIP: 0010:__read_once_size include/linux/compiler.h:179 [inline] > RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:31 [inline] > RIP: 0010:atomic_read include/asm-generic/atomic-instrumented.h:22 [inline] > RIP: 0010:refcount_inc_not_zero_checked+0xbb/0x2f0 lib/refcount.c:120 > Code: e7 e8 89 4b 30 fe 4c 89 e0 48 c1 e8 03 0f b6 14 18 4c 89 e0 83 e0 > 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 0b 02 00 00 49 8d 5d c0 <45> 8b 3c > 24 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 0f > kobject: 'queues' (00000000da0a0759): kobject_uevent_env: filter > function caused the event to drop! > RSP: 0018:ffff88017cf9f618 EFLAGS: 00010246 > RAX: 0000000000000003 RBX: ffff88017cf9f690 RCX: ffffffff83929317 > RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffc90001b356b0 > RBP: ffff88017cf9f6f8 R08: fffff52000366ad7 R09: fffff52000366ad6 > R10: fffff52000366ad6 R11: ffffc90001b356b3 R12: ffffc90001b356b0 > R13: ffff88017cf9f6d0 R14: ffffffff892b6d60 R15: ffff8801d4803400 > FS: 00007fb683cfa700(0000) GS:ffff8801daf00000(0000) > knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > kobject: 'loop1' (00000000bc5d5992): kobject_uevent_env > CR2: ffffc90001b356b0 CR3: 00000001d2369000 CR4: 00000000001426e0 > netlink: 72 bytes leftover after parsing attributes in process > `syz-executor3'. > Call Trace: > refcount_inc_checked+0x15/0x70 lib/refcount.c:153 > kobject: 'loop1' (00000000bc5d5992): fill_kobj_path: path = > '/devices/virtual/block/loop1' > kvm_get_kvm arch/x86/kvm/../../../virt/kvm/kvm_main.c:765 [inline] > kvm_ioctl_create_device arch/x86/kvm/../../../virt/kvm/kvm_main.c:2923 > [inline] > kvm_vm_ioctl+0xedf/0x1d60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3113 > vfs_ioctl fs/ioctl.c:46 [inline] > file_ioctl fs/ioctl.c:501 [inline] > do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 > ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 > __do_sys_ioctl fs/ioctl.c:709 [inline] > __se_sys_ioctl fs/ioctl.c:707 [inline] > __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x457579 > Code: 1d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007fb683cf9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579 > RDX: 00000000200002c0 RSI: 00000000c00caee0 RDI: 0000000000000008 > RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb683cfa6d4 > R13: 00000000004bfbd1 R14: 00000000004cfc58 R15: 00000000ffffffff > Modules linked in: > CR2: ffffc90001b356b0 > ---[ end trace 6ee8acb8091e879f ]--- > RIP: 0010:__read_once_size include/linux/compiler.h:179 [inline] > RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:31 [inline] > RIP: 0010:atomic_read include/asm-generic/atomic-instrumented.h:22 [inline] > RIP: 0010:refcount_inc_not_zero_checked+0xbb/0x2f0 lib/refcount.c:120 > Code: e7 e8 89 4b 30 fe 4c 89 e0 48 c1 e8 03 0f b6 14 18 4c 89 e0 83 e0 > 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 0b 02 00 00 49 8d 5d c0 <45> 8b 3c > 24 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 0f > RSP: 0018:ffff88017cf9f618 EFLAGS: 00010246 > RAX: 0000000000000003 RBX: ffff88017cf9f690 RCX: ffffffff83929317 > RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffc90001b356b0 > RBP: ffff88017cf9f6f8 R08: fffff52000366ad7 R09: fffff52000366ad6 > R10: fffff52000366ad6 R11: ffffc90001b356b3 R12: ffffc90001b356b0 > R13: ffff88017cf9f6d0 R14: ffffffff892b6d60 R15: ffff8801d4803400 > FS: 00007fb683cfa700(0000) GS:ffff8801daf00000(0000) > knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: ffffc90001b356b0 CR3: 00000001d2369000 CR4: 00000000001426e0 > > > --- > 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 syzkal...@googlegroups.com. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with > syzbot. >
#syz dup: WARNING: refcount bug in kvm_vm_ioctl
