Not allocated shadow for addr ffff8801a1400000 (page ffffea0009c78000)
Attempted to access 4096 bytes
------------[ cut here ]------------
kernel BUG at mm/kmsan/kmsan.c:1326!
invalid opcode: 0000 [#1] SMP PTI
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4524 Comm: syz-executor255 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kmsan_get_shadow_address+0x1ce/0x1f0 mm/kmsan/kmsan.c:1325
RSP: 0018:ffff8801991cf880 EFLAGS: 00010086
RAX: 000000000000001e RBX: 0000000000000680 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
RBP: ffff8801991cf898 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801a1400000
R13: 0000000000008000 R14: 0000000000000001 R15: 0000000000001000
FS:  0000000000c06880(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020351ff0 CR3: 0000000198f5e000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kmsan_internal_memset_shadow mm/kmsan/kmsan.c:171 [inline]
 kmsan_internal_unpoison_shadow+0x5c/0xe0 mm/kmsan/kmsan.c:208
 kmsan_unpoison_shadow+0x66/0xb0 mm/kmsan/kmsan.c:222
 get_user_pages_fast+0x47b/0x760 mm/gup.c:1823
 iov_iter_get_pages+0x465/0x1810 lib/iov_iter.c:1074
 af_alg_make_sg+0xdf/0x6d0 crypto/af_alg.c:404
 hash_sendmsg+0x305/0x1110 crypto/algif_hash.c:99
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x440049
RSP: 002b:00007ffc008343e8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ffc00834410 RCX: 0000000000440049
RDX: fffffffffffffeee RSI: 00000000205c8f58 RDI: 0000000000000004
RBP: 00000000006cb018 R08: 0000000020351ff0 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000401910
R13: 00000000004019a0 R14: 0000000000000000 R15: 0000000000000000
Code: 75 29 48 c7 c7 fd 92 7d 8a 31 c0 e8 4d 68 86 ff 80 3c 25 e8 03 2c 8b 00 75 11 48 c7 c7 2d 93 7d 8a 31 c0 4c 89 fe e8 32 68 86 ff <0f> 0b eb fe 48 3d ff ff ff 1f 0f 87 a2 fe ff ff 48 8b 1c 25 10 
RIP: kmsan_get_shadow_address+0x1ce/0x1f0 mm/kmsan/kmsan.c:1325 RSP: ffff8801991cf880
---[ end trace 6bc7d282af698052 ]---