Hello, syzbot found the following issue on: HEAD commit: 5e60366d Merge tag 'fallthrough-fixes-clang-5.11-rc1' of g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11c7046b500000 kernel config: https://syzkaller.appspot.com/x/.config?x=db720fe37a6a41d8 dashboard link: https://syzkaller.appspot.com/bug?extid=e87846c48bf72bc85311 compiler: gcc (GCC) 10.1.0-syz 20200507 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e87846c48bf72bc85311@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================================ UBSAN: shift-out-of-bounds in arch/x86/kvm/mmu.h:52:16 shift exponent 64 is too large for 64-bit type 'long long unsigned int' CPU: 1 PID: 11156 Comm: syz-executor.1 Not tainted 5.10.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:395 rsvd_bits arch/x86/kvm/mmu.h:52 [inline] kvm_vcpu_after_set_cpuid.cold+0x35/0x3a arch/x86/kvm/cpuid.c:181 kvm_vcpu_ioctl_set_cpuid+0x28e/0x970 arch/x86/kvm/cpuid.c:273 kvm_arch_vcpu_ioctl+0x1091/0x2d70 arch/x86/kvm/x86.c:4699 kvm_vcpu_ioctl+0x7b9/0xdb0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3386 kvm_vcpu_compat_ioctl+0x1a2/0x340 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3430 __do_compat_sys_ioctl+0x1d3/0x230 fs/ioctl.c:842 do_syscall_32_irqs_on arch/x86/entry/common.c:78 [inline] __do_fast_syscall_32+0x56/0x80 arch/x86/entry/common.c:137 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:160 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7fe8549 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f55e20cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000004008ae8a RDX: 00000000200000c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ================================================================================ --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
