syzbot


WARNING in exception_type

Status: fixed on 2021/11/10 00:50
Reported-by: syzbot+200c08e88ae818f849ce@syzkaller.appspotmail.com
Fix commit: e7177339d7b5 Revert "KVM: x86: mmu: Add guest physical address check in translate_gpa()"
First crash: 524d, last: 524d

Cause bisection: failed (bisect log)
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 WARNING in exception_type 1 438d 438d 0/1 auto-closed as invalid on 2022/03/24 01:16

Sample crash report:
L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 8469 at arch/x86/kvm/x86.c:525 exception_type+0x98/0xb0 arch/x86/kvm/x86.c:525
Modules linked in:
CPU: 1 PID: 8469 Comm: syz-executor531 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:exception_type+0x98/0xb0 arch/x86/kvm/x86.c:525
Code: 31 ff 45 31 ed 44 89 e6 e8 25 75 69 00 45 85 e4 41 0f 95 c5 45 01 ed e8 d6 6d 69 00 44 89 e8 5b 41 5c 41 5d c3 e8 c8 6d 69 00 <0f> 0b e8 c1 6d 69 00 41 bd 03 00 00 00 5b 44 89 e8 41 5c 41 5d c3
RSP: 0018:ffffc90000f1f8f0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 00000000000000a2 RCX: 0000000000000000
RDX: ffff888018461c40 RSI: ffffffff810c3b28 RDI: 0000000000000003
RBP: ffff888020868000 R08: 000000000000001f R09: 00000000000000a2
R10: ffffffff810c3aaa R11: 0000000000000006 R12: 00000000000000a2
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000040
FS:  000000000179c300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffd362aad8 CR3: 00000000182ef000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 x86_emulate_instruction+0xef6/0x1460 arch/x86/kvm/x86.c:7853
 kvm_mmu_page_fault+0x2f0/0x1810 arch/x86/kvm/mmu/mmu.c:5199
 handle_ept_misconfig+0xdf/0x3e0 arch/x86/kvm/vmx/vmx.c:5336
 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6021 [inline]
 vmx_handle_exit+0x336/0x1800 arch/x86/kvm/vmx/vmx.c:6038
 vcpu_enter_guest+0x2a1c/0x4430 arch/x86/kvm/x86.c:9712
 vcpu_run arch/x86/kvm/x86.c:9779 [inline]
 kvm_arch_vcpu_ioctl_run+0x47d/0x1b20 arch/x86/kvm/x86.c:10010
 kvm_vcpu_ioctl+0x49e/0xe50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3652
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl fs/ioctl.c:1055 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x441159
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffd362c598 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 0000000000441159
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 0000000000404c50 R08: 0000000000400488 R09: 0000000000400488
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000404ce0
R13: 0000000000000000 R14: 00000000004ae018 R15: 0000000000400488

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-kasan-gce 2021/08/29 17:28 upstream 3f5ad13cb012 be2c130d .config console log report syz C WARNING in exception_type
* Struck through repros no longer work on HEAD.