On Mon, May 7, 2018 at 7:19 PM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > On 29/04/2018 19:00, syzbot wrote: >> Hello, >> >> syzbot hit the following crash on upstream commit >> bf8f5de17442bba5f811e7e724980730e079ee11 (Sat Apr 28 17:05:04 2018 +0000) >> MAINTAINERS: add myself as maintainer of AFFS >> syzbot dashboard link: >> https://syzkaller.appspot.com/bug?extid=35666cba7f0a337e2e79 >> >> C reproducer: https://syzkaller.appspot.com/x/repro.c?id=5686569910403072 >> syzkaller reproducer: >> https://syzkaller.appspot.com/x/repro.syz?id=5767017265102848 >> Raw console output: >> https://syzkaller.appspot.com/x/log.txt?id=6346308495343616 >> 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+35666cba7f0a337e2e79@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. >> >> ------------[ cut here ]------------ >> DEBUG_LOCKS_WARN_ON(__owner_task(owner) != current) >> WARNING: CPU: 0 PID: 4525 at kernel/locking/mutex.c:1032 >> __mutex_unlock_slowpath+0x62e/0x8a0 kernel/locking/mutex.c:1032 >> Kernel panic - not syncing: panic_on_warn set ... > > This doesn't make much sense, unless it's a "generic" memory corruption, > but at least the reproducer seems to be simple, just (in pseudocode) > > ioctl(kvm_vm_fd, KVM_HYPERV_EVENTFD, > { fd = some_eventfd, conn_id = 0, flags = 0 }) > ioctl(kvm_vm_fd, KVM_HYPERV_EVENTFD, > { fd = -1, conn_id = 5, flags = KVM_HYPERV_EVENTFD_DEASSIGN }) > > Roman, Cathy, can you give it a quick look? (Reproducing the reproducer > link: https://syzkaller.appspot.com/x/repro.c?id=5686569910403072). > > Paolo May be related to: https://syzkaller.appspot.com/bug?id=aec313f3f7ebc2ee0abb1104a3631ab8fd1e90f2 >> CPU: 0 PID: 4525 Comm: syz-executor809 Not tainted 4.17.0-rc2+ #22 >> 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+0x1b9/0x294 lib/dump_stack.c:113 >> panic+0x22f/0x4de kernel/panic.c:184 >> __warn.cold.8+0x163/0x1b3 kernel/panic.c:536 >> report_bug+0x252/0x2d0 lib/bug.c:186 >> fixup_bug arch/x86/kernel/traps.c:178 [inline] >> do_error_trap+0x1de/0x490 arch/x86/kernel/traps.c:296 >> do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 >> invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992 >> RIP: 0010:__mutex_unlock_slowpath+0x62e/0x8a0 kernel/locking/mutex.c:1032 >> RSP: 0018:ffff8801cf31f138 EFLAGS: 00010286 >> RAX: 0000000000000033 RBX: 1ffff10039e63e30 RCX: ffffffff8160b82d >> RDX: 0000000000000000 RSI: ffffffff816104e1 RDI: 0000000000000001 >> RBP: ffff8801cf31f2a8 R08: ffff8801d9042180 R09: fffffbfff11b0974 >> R10: fffffbfff11b0974 R11: ffffffff88d84ba3 R12: ffffffff8a713a20 >> R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8801989d6b08 >> mutex_unlock+0xd/0x10 kernel/locking/mutex.c:614 >> kvm_hv_eventfd_deassign arch/x86/kvm/hyperv.c:1434 [inline] >> kvm_vm_ioctl_hv_eventfd+0x1ea/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: 0033:0x4401f9 >> RSP: 002b:00007ffcd5727a48 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 >> RAX: ffffffffffffffda RBX: 6d766b2f7665642f RCX: 00000000004401f9 >> RDX: 0000000020000140 RSI: 000000004018aebd RDI: 00000000000000ee >> RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 >> R10: 00000000004002c8 R11: 0000000000000217 R12: 0000000000401720 >> R13: 00000000004017b0 R14: 0000000000000000 R15: 0000000000000000 >> Dumping ftrace buffer: >> (ftrace buffer empty) >> Kernel Offset: disabled >> Rebooting in 86400 seconds.. >> >> >> --- >> 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/59d3e273-293d-7597-7d69-b5278318a026%40redhat.com. > For more options, visit https://groups.google.com/d/optout.
