KASAN: stack-out-of-bounds Read in do_general_protection

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    62d18ecfa641 Merge tag 'arm64-fixes' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1093ccb7800000
kernel config:  https://syzkaller.appspot.com/x/.config?x=982e2df1b9e60b02
dashboard link: https://syzkaller.appspot.com/bug?extid=a5373bacd7643643b238
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
userspace arch: i386
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=1067742f800000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+a5373bacd7643643b238@xxxxxxxxxxxxxxxxxxxxxxxxx

IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready
8021q: adding VLAN 0 to HW filter on device team0
==================================================================
BUG: KASAN: stack-out-of-bounds in do_general_protection+0x2ac/0x2f0  
arch/x86/kernel/traps.c:538
Read of size 8 at addr ffff8801b21273f8 by task syz-executor0/5106

CPU: 0 PID: 5106 Comm: syz-executor0 Not tainted 4.17.0-rc6+ #92
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+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 do_general_protection+0x2ac/0x2f0 arch/x86/kernel/traps.c:538
 general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1159
RIP: 0010:msr_write_intercepted arch/x86/kvm/vmx.c:2132 [inline]
RIP: 0010:vmx_vcpu_run+0xa12/0x25c0 arch/x86/kvm/vmx.c:9879
RSP: 0018:ffff8801b2127410 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: 0000000010000000 RCX: ffffffff811f76f2
RDX: 000000000836b156 RSI: ffffffff811f76ff RDI: 0000000000000005
RBP: ffff8801b2127508 R08: ffff8801cf7a6500 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 mmu_notifier_release include/linux/mmu_notifier.h:244 [inline]
 exit_mmap+0xa4/0x5a0 mm/mmap.c:3057
 __mmput kernel/fork.c:961 [inline]
 mmput+0x251/0x610 kernel/fork.c:982
 exit_mm kernel/exit.c:544 [inline]
 do_exit+0xe98/0x2730 kernel/exit.c:852
 do_group_exit+0x16f/0x430 kernel/exit.c:968
 __do_sys_exit_group kernel/exit.c:979 [inline]
 __se_sys_exit_group kernel/exit.c:977 [inline]
 __ia32_sys_exit_group+0x3e/0x50 kernel/exit.c:977
 do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline]
 do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f88cb9
RSP: 002b:00000000f7f7fa8c EFLAGS: 00000286 ORIG_RAX: 00000000000000fc
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0006c849c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea0006c80101 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b2127280: 00 f2 00 00 00 00 00 00 00 00 00 00 00 00 f3 00
 ffff8801b2127300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> ffff8801b2127380: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f8 f2 f2 f2
                                                                ^
 ffff8801b2127400: f2 f2 f2 f2 f8 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2
 ffff8801b2127480: f2 f2 f2 f2 00 f2 f2 f2 f3 f3 f3 f3 00 00 00 00
==================================================================


---
This bug 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@xxxxxxxxxxxxxxxxx

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with  
syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches