syzbot
KASAN: vmalloc-out-of-bounds Write in kvm_dev_ioctl_get_cpuid
Status:
fixed on 2020/01/08 01:07
Subsystems:
kvm-x86
[Documentation on labels]
Reported-by: syzbot+e3f4897236c4eeb8af4f@syzkaller.appspotmail.com
Fix commit:
433f4ba19041
KVM: x86: fix out-of-bounds write in KVM_GET_EMULATED_CPUID (CVE-2019-19332)
First crash: 2460d, last: 2456d
Sample crash report:
==================================================================
BUG: KASAN: vmalloc-out-of-bounds in __do_cpuid_func_emulated arch/x86/kvm/cpuid.c:323 [inline]
BUG: KASAN: vmalloc-out-of-bounds in do_cpuid_func arch/x86/kvm/cpuid.c:814 [inline]
BUG: KASAN: vmalloc-out-of-bounds in do_cpuid_func arch/x86/kvm/cpuid.c:810 [inline]
BUG: KASAN: vmalloc-out-of-bounds in kvm_dev_ioctl_get_cpuid+0xad7/0xb0b arch/x86/kvm/cpuid.c:891
Write of size 4 at addr ffffc90000d36050 by task syz-executor885/9172
CPU: 0 PID: 9172 Comm: syz-executor885 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x197/0x210 lib/dump_stack.c:118
print_address_description.constprop.0.cold+0x5/0x30b mm/kasan/report.c:374
__kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
kasan_report+0x12/0x20 mm/kasan/common.c:638
__asan_report_store4_noabort+0x17/0x20 mm/kasan/generic_report.c:139
__do_cpuid_func_emulated arch/x86/kvm/cpuid.c:323 [inline]
do_cpuid_func arch/x86/kvm/cpuid.c:814 [inline]
do_cpuid_func arch/x86/kvm/cpuid.c:810 [inline]
kvm_dev_ioctl_get_cpuid+0xad7/0xb0b arch/x86/kvm/cpuid.c:891
kvm_arch_dev_ioctl+0x300/0x4b0 arch/x86/kvm/x86.c:3387
kvm_dev_ioctl+0x127/0x17d0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3593
vfs_ioctl fs/ioctl.c:47 [inline]
file_ioctl fs/ioctl.c:545 [inline]
do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732
ksys_ioctl+0xab/0xd0 fs/ioctl.c:749
__do_sys_ioctl fs/ioctl.c:756 [inline]
__se_sys_ioctl fs/ioctl.c:754 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4401e9
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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff9da443c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401e9
RDX: 0000000020000000 RSI: 00000000c008ae09 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a70
R13: 0000000000401b00 R14: 0000000000000000 R15: 0000000000000000
Memory state around the buggy address:
ffffc90000d35f00: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
ffffc90000d35f80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
>ffffc90000d36000: 00 00 00 00 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9
^
ffffc90000d36080: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
ffffc90000d36100: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
==================================================================
* Struck through repros no longer work on HEAD.