==================================================================
BUG: KASAN: stack-out-of-bounds in zap_pmd_range mm/memory.c:1421 [inline]
BUG: KASAN: stack-out-of-bounds in zap_pud_range mm/memory.c:1466 [inline]
BUG: KASAN: stack-out-of-bounds in zap_p4d_range mm/memory.c:1487 [inline]
BUG: KASAN: stack-out-of-bounds in unmap_page_range+0x1dde/0x2220 mm/memory.c:1508
Read of size 8 at addr ffff880198fdd3c8 by task syz-executor0/20351

CPU: 0 PID: 20351 Comm: syz-executor0 Not tainted 4.18.0-rc3+ #1
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+0x1c9/0x2b4 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
PANIC: double fault, error_code: 0x0
 zap_pmd_range mm/memory.c:1421 [inline]
 zap_pud_range mm/memory.c:1466 [inline]
 zap_p4d_range mm/memory.c:1487 [inline]
 unmap_page_range+0x1dde/0x2220 mm/memory.c:1508
CPU: 1 PID: 20360 Comm: syz-executor1 Not tainted 4.18.0-rc3+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:778 [inline]
RIP: 0010:__lock_acquire+0xb1c/0x5020 kernel/locking/lockdep.c:3311
Code: 88 
48 b8 
00 00 
00 00 
00 fc 
ff df 
48 89 
fa 48 
c1 ea 
03 80 
3c 02 
00 0f 
85 0d 
31 00 
00 48 
83 3d 
0a fd 
92 07 
00 0f 
84 d3 
0a 00 
00 <9c> 
58 0f 
1f 44 
00 00 
f6 c4 
02 0f 
 unmap_single_vma+0x1a0/0x310 mm/memory.c:1553
84 63 
 unmap_vmas+0x120/0x1f0 mm/memory.c:1583
f6 ff 
 exit_mmap+0x2c2/0x5b0 mm/mmap.c:3105
ff e8 
3f 32 
fd 01 
 __mmput kernel/fork.c:970 [inline]
 mmput+0x265/0x620 kernel/fork.c:991
85 
RSP: 0018:ffff880195bfffe0 EFLAGS: 00010082
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 1ffffffff11e360c RSI: 0000000000000000 RDI: ffffffff88f1b060
RBP: ffff880195c00370 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000000
R13: ffffffff88f92620 R14: ffff88019c3c4700 R15: 0000000000000002
FS:  00007fba09739700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff880195bfffd8 CR3: 00000001d4a02000 CR4: 00000000001406e0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 exit_mm kernel/exit.c:544 [inline]
 do_exit+0xea9/0x2750 kernel/exit.c:852