list_add corruption. next->prev should be prev (ffff88021fffac50), but was ffffea000b051420. (next=ffffea000ac1c420).
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:25!
invalid opcode: 0000 [#1] SMP PTI
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4518 Comm: syz-executor0 Not tainted 4.17.0-rc5+ #102
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_add_valid+0x275/0x450 lib/list_debug.c:23
RSP: 0018:ffff88014457f6d8 EFLAGS: 00010086
RAX: 0000000000000075 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88021fd36eec
RBP: ffff88014457f740 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea000ac1c420
R13: ffffea000b051420 R14: 0000000000000000 R15: ffffffff8b58b000
FS:  0000000001de3940(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb8603b5360 CR3: 0000000144568000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __list_add include/linux/list.h:60 [inline]
 list_add include/linux/list.h:79 [inline]
 __free_one_page+0x1483/0x1800 mm/page_alloc.c:876
 free_one_page mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x87f/0x16c0 mm/page_alloc.c:1260
 __free_pages+0x109/0x240 mm/page_alloc.c:4442
 kmsan_free_page+0x1b6/0x2e0 mm/kmsan/kmsan.c:959
 free_pages_prepare mm/page_alloc.c:996 [inline]
 __free_pages_ok+0x270/0x16c0 mm/page_alloc.c:1254
 __free_pages+0x109/0x240 mm/page_alloc.c:4442
 free_thread_stack kernel/fork.c:267 [inline]
 release_task_stack kernel/fork.c:354 [inline]
 put_task_stack+0x233/0x2f0 kernel/fork.c:365
 finish_task_switch+0x17c/0x270 kernel/sched/core.c:2741
 context_switch kernel/sched/core.c:2866 [inline]
 __schedule+0x688/0x730 kernel/sched/core.c:3507
 schedule+0x1cc/0x2f0 kernel/sched/core.c:3551
 freezable_schedule include/linux/freezer.h:172 [inline]
 do_nanosleep+0x2c3/0x9b0 kernel/time/hrtimer.c:1689
 hrtimer_nanosleep kernel/time/hrtimer.c:1743 [inline]
 __do_sys_nanosleep kernel/time/hrtimer.c:1775 [inline]
 __se_sys_nanosleep+0x4b3/0x6a0 kernel/time/hrtimer.c:1762
 __x64_sys_nanosleep+0x92/0xc0 kernel/time/hrtimer.c:1762
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x481110
RSP: 002b:0000000000a3ea98 EFLAGS: 00000246 ORIG_RAX: 0000000000000023
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000481110
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000a3eaa0
RBP: 0000000000018725 R08: 0000000000000001 R09: 0000000001de3940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000002 R14: 0000000000000106 R15: 00000000000186f2
Code: 87 80 0c 00 00 00 00 00 00 41 c7 87 20 03 00 00 00 00 00 00 48 c7 c7 d4 77 a5 8a 31 c0 48 89 d6 4c 89 ea 4c 89 e1 e8 5b 7d 42 fd <0f> 0b 66 0f 1f 84 00 00 00 00 00 eb fe 48 8b 7d c8 e8 45 aa bf 
RIP: __list_add_valid+0x275/0x450 lib/list_debug.c:23 RSP: ffff88014457f6d8
---[ end trace e1573cb37c707416 ]---