kernel BUG at include/linux/kvm_host.h:LINE!

From: syzbot
Date: Mon Jul 01 2019 - 13:44:09 EST


Hello,

syzbot found the following crash on:

HEAD commit: 6fbc7275 Linux 5.2-rc7
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16d8d2cda00000
kernel config: https://syzkaller.appspot.com/x/.config?x=f6451f0da3d42d53
dashboard link: https://syzkaller.appspot.com/bug?extid=bfdba32e6c49af090931
compiler: gcc (GCC) 9.0.0 20181231 (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+bfdba32e6c49af090931@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
kernel BUG at include/linux/kvm_host.h:579!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5546 Comm: syz-executor.4 Not tainted 5.2.0-rc7 #65
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kvm_vcpu_get_idx include/linux/kvm_host.h:579 [inline]
RIP: 0010:kvm_vcpu_get_idx include/linux/kvm_host.h:571 [inline]
RIP: 0010:kvm_hv_set_msr arch/x86/kvm/hyperv.c:1082 [inline]
RIP: 0010:kvm_hv_set_msr_common+0x241d/0x2ab0 arch/x86/kvm/hyperv.c:1303
Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 c6 03 00 00 48 8b 85 28 ff ff ff 45 31 e4 49 89 87 20 2e 00 00 e9 10 dd ff ff e8 53 aa 58 00 <0f> 0b 4c 89 ff e8 29 58 91 00 e9 8d de ff ff 4c 89 ff e8 1c 58 91
RSP: 0018:ffff88804f8a73d8 EFLAGS: 00010216
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc9000e83e000
RDX: 0000000000001051 RSI: ffffffff811818ed RDI: 0000000000000004
RBP: ffff88804f8a74f0 R08: ffff888061eda0c0 R09: fffff52002c4bb3b
R10: fffff52002c4bb3a R11: ffffc9001625d9d3 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffc9001625d9d0 R15: ffff888057209980
FS: 00007f8cdaf27700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd93ee22db8 CR3: 00000000993e9000 CR4: 00000000001426f0
Call Trace:
kvm_set_msr_common+0xb8f/0x2570 arch/x86/kvm/x86.c:2662
vmx_set_msr+0x710/0x21d0 arch/x86/kvm/vmx/vmx.c:2030
kvm_set_msr+0x18a/0x370 arch/x86/kvm/x86.c:1359
do_set_msr+0xa6/0xf0 arch/x86/kvm/x86.c:1388
__msr_io arch/x86/kvm/x86.c:2975 [inline]
msr_io+0x1ad/0x2e0 arch/x86/kvm/x86.c:3011
kvm_arch_vcpu_ioctl+0x12be/0x3000 arch/x86/kvm/x86.c:4032
kvm_vcpu_ioctl+0x8f6/0xf90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2905
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696
ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459519
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8cdaf26c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459519
RDX: 0000000020000280 RSI: 000000004008ae89 RDI: 0000000000000005
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8cdaf276d4
R13: 00000000004c249d R14: 00000000004d5708 R15: 00000000ffffffff
Modules linked in:
---[ end trace 4d93e12c89ced131 ]---
RIP: 0010:kvm_vcpu_get_idx include/linux/kvm_host.h:579 [inline]
RIP: 0010:kvm_vcpu_get_idx include/linux/kvm_host.h:571 [inline]
RIP: 0010:kvm_hv_set_msr arch/x86/kvm/hyperv.c:1082 [inline]
RIP: 0010:kvm_hv_set_msr_common+0x241d/0x2ab0 arch/x86/kvm/hyperv.c:1303
Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 c6 03 00 00 48 8b 85 28 ff ff ff 45 31 e4 49 89 87 20 2e 00 00 e9 10 dd ff ff e8 53 aa 58 00 <0f> 0b 4c 89 ff e8 29 58 91 00 e9 8d de ff ff 4c 89 ff e8 1c 58 91
RSP: 0018:ffff88804f8a73d8 EFLAGS: 00010216
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc9000e83e000
RDX: 0000000000001051 RSI: ffffffff811818ed RDI: 0000000000000004
RBP: ffff88804f8a74f0 R08: ffff888061eda0c0 R09: fffff52002c4bb3b
R10: fffff52002c4bb3a R11: ffffc9001625d9d3 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffc9001625d9d0 R15: ffff888057209980
FS: 00007f8cdaf27700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdcaa36dec CR3: 00000000993e9000 CR4: 00000000001426f0


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