general protection fault in __apic_accept_irq

syzbot
2019-09-05T08:28:09Z

Hello,

syzbot found the following crash on:

HEAD commit: 3b47fd5c Merge tag 'nfs-for-5.3-4' of git://git.linux-nfs...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=124af12a600000
kernel config: https://syzkaller.appspot.com/x/.config?x=144488c6c6c6d2b6
dashboard link: https://syzkaller.appspot.com/bug?extid=dff25ee91f0c7d5c1695
compiler: clang version 9.0.0 (/home/glider/llvm/clang
80fee25776c2fb61e74c1ecb1a523375c2500b69)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10954676600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1752fe0a600000

The bug was bisected to:

commit 0aa67255f54df192d29aec7ac6abb1249d45bda7
Author: Vitaly Kuznetsov <vkuznets@redhat.com>
Date: Mon Nov 26 15:47:29 2018 +0000

x86/hyper-v: move synic/stimer control structures definitions to
hyperv-tlfs.h

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=156128c1600000
console output: https://syzkaller.appspot.com/x/log.txt?x=136128c1600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+dff25ee91f0c7d5c1695@syzkaller.appspotmail.com
Fixes: 0aa67255f54d ("x86/hyper-v: move synic/stimer control structures
definitions to hyperv-tlfs.h")

kvm [9347]: vcpu0, guest rIP: 0xcc Hyper-V uhandled wrmsr: 0x40000004 data
0x94
kvm [9347]: vcpu0, guest rIP: 0xcc Hyper-V uhandled wrmsr: 0x40000004 data
0x48c
kvm [9347]: vcpu0, guest rIP: 0xcc Hyper-V uhandled wrmsr: 0x40000004 data
0x4ac
kvm [9347]: vcpu0, guest rIP: 0xcc Hyper-V uhandled wrmsr: 0x40000005 data
0x1520
kvm [9347]: vcpu0, guest rIP: 0xcc Hyper-V uhandled wrmsr: 0x40000006 data
0x15d4
kvm [9347]: vcpu0, guest rIP: 0xcc Hyper-V uhandled wrmsr: 0x40000007 data
0x15c4
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9347 Comm: syz-executor665 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__apic_accept_irq+0x46/0x740 arch/x86/kvm/lapic.c:1029
Code: 89 55 cc 41 89 f4 48 89 fb 49 bd 00 00 00 00 00 fc ff df e8 5c c9 5d
00 48 89 5d c0 4c 8d b3 98 00 00 00 4d 89 f7 49 c1 ef 03 <43> 80 3c 2f 00
74 08 4c 89 f7 e8 6b c4 96 00 49 8b 06 48 89 45 d0
RSP: 0018:ffff88808a30f9b0 EFLAGS: 00010202
RAX: ffffffff8115c384 RBX: 0000000000000000 RCX: ffff8880977f2140
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88808a30fa10 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed1011461f64 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000098 R15: 0000000000000013
FS: 0000555555e35880(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000008f96d000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kvm_apic_set_irq+0xb4/0x140 arch/x86/kvm/lapic.c:558
stimer_notify_direct arch/x86/kvm/hyperv.c:648 [inline]
stimer_expiration arch/x86/kvm/hyperv.c:659 [inline]
kvm_hv_process_stimers+0x594/0x1650 arch/x86/kvm/hyperv.c:686
vcpu_enter_guest+0x2b2a/0x54b0 arch/x86/kvm/x86.c:7896
vcpu_run+0x393/0xd40 arch/x86/kvm/x86.c:8152
kvm_arch_vcpu_ioctl_run+0x636/0x900 arch/x86/kvm/x86.c:8360
kvm_vcpu_ioctl+0x6cf/0xaf0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2765
do_vfs_ioctl+0x744/0x1730 fs/ioctl.c:46
ksys_ioctl fs/ioctl.c:713 [inline]
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0xe3/0x120 fs/ioctl.c:718
do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x442a19
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 1b 0c fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffca3d2a208 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000442a19
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00000000006cd018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000403ac0
R13: 0000000000403b50 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 8515c4c18eb55117 ]---
RIP: 0010:__apic_accept_irq+0x46/0x740 arch/x86/kvm/lapic.c:1029
Code: 89 55 cc 41 89 f4 48 89 fb 49 bd 00 00 00 00 00 fc ff df e8 5c c9 5d
00 48 89 5d c0 4c 8d b3 98 00 00 00 4d 89 f7 49 c1 ef 03 <43> 80 3c 2f 00
74 08 4c 89 f7 e8 6b c4 96 00 49 8b 06 48 89 45 d0
RSP: 0018:ffff88808a30f9b0 EFLAGS: 00010202
RAX: ffffffff8115c384 RBX: 0000000000000000 RCX: ffff8880977f2140
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88808a30fa10 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed1011461f64 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000098 R15: 0000000000000013
FS: 0000555555e35880(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000008f96d000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

---
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