On Sun, Apr 29, 2018 at 7:00 PM, syzbot <syzbot+549decbd1891d501b6d5@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hello, > > syzbot hit the following crash on upstream commit > cdface5209349930ae1b51338763c8e029971b97 (Sun Apr 29 03:07:21 2018 +0000) > Merge tag 'for_linus_stable' of > git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 > syzbot dashboard link: > https://syzkaller.appspot.com/bug?extid=549decbd1891d501b6d5 > > So far this crash happened 8 times on upstream. > C reproducer: https://syzkaller.appspot.com/x/repro.c?id=6647588371562496 > syzkaller reproducer: > https://syzkaller.appspot.com/x/repro.syz?id=4781854846615552 > Raw console output: > https://syzkaller.appspot.com/x/log.txt?id=4580574157078528 > Kernel config: > https://syzkaller.appspot.com/x/.config?id=7043958930931867332 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+549decbd1891d501b6d5@xxxxxxxxxxxxxxxxxxxxxxxxx > It will help syzbot understand when the bug is fixed. See footer for > details. > If you forward the report, please keep this part and the footer. This crash was bisected as introduced by: commit faeb7833eee0d6afe0ecb6bdfa6042556c2c352e Author: Roman Kagan <rkagan@xxxxxxxxxxxxx> Date: Thu Feb 1 16:48:32 2018 +0300 kvm: x86: hyperv: guest->host event signaling via eventfd https://gist.githubusercontent.com/dvyukov/df4971d7dfd1b37bedb5bfa0c95f9ebc/raw/ee8b7804788049f80625563e0322090c798c4544/gistfile1.txt > kasan: CONFIG_KASAN_INLINE enabled > kasan: GPF could be caused by NULL-ptr deref or user memory access > general protection fault: 0000 [#1] SMP KASAN > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 0 PID: 4525 Comm: syz-executor786 Not tainted 4.17.0-rc2+ #23 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline] > RIP: 0010:__radix_tree_delete+0x74/0x230 lib/radix-tree.c:1989 > RSP: 0018:ffff8801d9137108 EFLAGS: 00010206 > RAX: 0000000000000003 RBX: dffffc0000000000 RCX: 1ffff1003b226e3e > RDX: 0000000000000000 RSI: ffffffff8768eeed RDI: ffff8801a7dac168 > RBP: ffff8801d91371a8 R08: ffff8801d962c1c0 R09: ffffed0034fb5811 > R10: ffff8801d91372b8 R11: ffff8801a7dac08f R12: 0000000000000000 > R13: ffff8801a7dac168 R14: 0000000000000018 R15: ffff8801d9137230 > FS: 0000000001df3880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000100 CR3: 00000001d9104000 CR4: 00000000001426f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > radix_tree_delete_item+0x148/0x2d0 lib/radix-tree.c:2050 > idr_remove+0x46/0x60 lib/idr.c:157 > kvm_hv_eventfd_deassign arch/x86/kvm/hyperv.c:1433 [inline] > kvm_vm_ioctl_hv_eventfd+0x1df/0x24b arch/x86/kvm/hyperv.c:1451 > kvm_arch_vm_ioctl+0x155e/0x2690 arch/x86/kvm/x86.c:4563 > kvm_vm_ioctl+0x246/0x1d90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3100 > vfs_ioctl fs/ioctl.c:46 [inline] > file_ioctl fs/ioctl.c:500 [inline] > do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684 > ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 > __do_sys_ioctl fs/ioctl.c:708 [inline] > __se_sys_ioctl fs/ioctl.c:706 [inline] > __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706 > do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x440069 > RSP: 002b:00007ffcf0b02cd8 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 6d766b2f7665642f RCX: 0000000000440069 > RDX: 0000000020000000 RSI: 000000004018aebd RDI: 00000000000000a9 > RBP: 00000000006cb018 R08: 00007ffcf0b02cf0 R09: 00007ffcf0b02cf0 > R10: 00007ffcf0b02cf0 R11: 0000000000000217 R12: 00000000004018a0 > R13: 0000000000401930 R14: 0000000000000000 R15: 0000000000000000 > Code: 3f 9a 88 48 c7 45 88 80 ee 68 87 c7 00 f1 f1 f1 f1 c7 40 04 00 f2 f2 > f2 c7 40 08 f3 f3 f3 f3 e8 a3 51 10 fa 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 0f > 85 97 01 00 00 48 8d 55 d8 4c 8d 7a c0 49 8b 1e > RIP: __read_once_size include/linux/compiler.h:188 [inline] RSP: > ffff8801d9137108 > RIP: __radix_tree_delete+0x74/0x230 lib/radix-tree.c:1989 RSP: > ffff8801d9137108 > ---[ end trace 79327005f044daef ]--- > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. > If you forgot to add the Reported-by tag, once the fix for this bug is > merged > into any tree, please reply to this email with: > #syz fix: exact-commit-title > If you want to test a patch for this bug, please reply with: > #syz test: git://repo/address.git branch > and provide the patch inline or as an attachment. > 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 > Note: if the crash happens again, it will cause creation of a new bug > report. > Note: all commands must start from beginning of the line in the email body. > > -- > 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/00000000000011cf3a056affabfd%40google.com. > For more options, visit https://groups.google.com/d/optout.
