On Fri, 27 Oct 2017 01:34:01 -0700, syzbot wrote: > Hello, > > syzkaller hit the following crash on > bb70832dd42b298d4303fd054bf18a78650ff04a > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > > syzkaller reproducer is attached. See https://goo.gl/kgGztJ > for information about syzkaller reproducers > > > kernel BUG at arch/x86/kvm/x86.c:7150! > invalid opcode: 0000 [#1] SMP KASAN > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 3 PID: 3029 Comm: syz-executor0 Not tainted 4.13.0-rc5-next-20170817+ > #5 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > task: ffff88006c488700 task.stack: ffff880067800000 > RIP: 0010:complete_emulated_mmio+0x5be/0x6f0 arch/x86/kvm/x86.c:7150 > RSP: 0018:ffff880067807620 EFLAGS: 00010297 > RAX: ffff88006c488700 RBX: ffff880039428040 RCX: ffff88003942845c > RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880039428260 > RBP: ffff880067807660 R08: 0000000000000000 R09: ffffed000cf00f2c > R10: ffff880067807a58 R11: ffff8800678079d0 R12: ffffffff810d0840 > R13: ffff880039c71000 R14: ffff88006da89f00 R15: ffff880039428040 > FS: 00007f8311e83700(0000) GS:ffff88006df00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f04f6102000 CR3: 000000003d5de000 CR4: 00000000000026e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > kvm_arch_vcpu_ioctl_run+0x2e2b/0x58b0 arch/x86/kvm/x86.c:7220 > kvm_vcpu_ioctl+0x64c/0x1010 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2591 > vfs_ioctl fs/ioctl.c:45 [inline] > do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685 > SYSC_ioctl fs/ioctl.c:700 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 > entry_SYSCALL_64_fastpath+0x1f/0xbe > RIP: 0033:0x446749 > RSP: 002b:00007f8311e82c08 EFLAGS: 00000282 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000446749 > RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 > RBP: 0000000000a5f870 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000282 R12: 0000000000000000 > R13: 0000000000000000 R14: 00007f8311e839c0 R15: 00007f8311e83700 > Code: 01 00 00 00 48 89 df e8 51 9e 47 00 44 89 e6 4c 89 f7 45 31 e4 e8 93 > 25 4d 00 45 85 ed 41 0f 94 c4 e9 c5 fc ff ff e8 f2 2e 60 00 <0f> 0b e8 1b > 99 94 00 e9 a0 fa ff ff 89 45 c8 e8 0e 99 94 00 8b > RIP: complete_emulated_mmio+0x5be/0x6f0 arch/x86/kvm/x86.c:7150 RSP: > ffff880067807620 > ---[ end trace f2b488a12d890bf5 ]--- > Kernel panic - not syncing: Fatal exception > 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 syzk...@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. > Once a fix for this bug is committed, please reply to this email with: > #syz fix: exact-commit-title Just to follow up on this bug: this crash is no longer occurring and it seems to have been fixed since v4.15-rc2 by commit 61cb57c9ed631c, so telling syzbot: #syz fix: KVM: x86: Exit to user-mode on #UD intercept when emulator requires - Eric
