list_add corruption. next->prev should be prev (00000000a7bb0694), but was 000000007266314b. (next=000000007266314b).
------------[ 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: 8502 Comm: syz-executor2 Not tainted 4.16.0+ #84
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:ffff88016537f0c0 EFLAGS: 00010082
RAX: 0000000000000075 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88021fd30418
RBP: ffff88016537f128 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88021fffab70
R13: ffff88021fffab70 R14: 0000000000000000 R15: ffffffff8832e000
FS:  00007feb59180700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f80eccc9000 CR3: 000000016ae40000 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:915
 free_one_page mm/page_alloc.c:1185 [inline]
 __free_pages_ok+0x87f/0x16b0 mm/page_alloc.c:1276
 __free_pages+0x109/0x240 mm/page_alloc.c:4323
 kmsan_free_page+0x197/0x2e0 mm/kmsan/kmsan.c:938
 free_pages_prepare mm/page_alloc.c:1035 [inline]
 __free_pages_ok+0x270/0x16b0 mm/page_alloc.c:1270
 __free_pages mm/page_alloc.c:4323 [inline]
 free_pages+0x1e7/0x320 mm/page_alloc.c:4333
 _pgd_free arch/x86/mm/pgtable.c:366 [inline]
 pgd_free+0x2b2/0x360 arch/x86/mm/pgtable.c:415
 mm_free_pgd kernel/fork.c:552 [inline]
 __mmdrop+0xb7/0x840 kernel/fork.c:598
 mmdrop include/linux/sched/mm.h:49 [inline]
 __mmput+0x559/0x610 kernel/fork.c:971
 mmput+0xab/0xf0 kernel/fork.c:982
 exit_mm+0x6ed/0x7a0 kernel/exit.c:545
 do_exit+0xc01/0x38d0 kernel/exit.c:854
 do_group_exit+0x1a0/0x360 kernel/exit.c:970
 get_signal+0x1320/0x1f20 kernel/signal.c:2469
 do_signal+0xb8/0x1c80 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop arch/x86/entry/common.c:162 [inline]
 prepare_exit_to_usermode+0x271/0x3a0 arch/x86/entry/common.c:196
 syscall_return_slowpath+0xe9/0x700 arch/x86/entry/common.c:265
 do_syscall_64+0x36d/0x430 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x455329
RSP: 002b:00007feb5917fce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 000000000072bec8 RCX: 0000000000455329
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000072bec8
RBP: 000000000072bec8 R08: 0000000000000000 R09: 000000000072bea0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000a3e81f R14: 00007feb591809c0 R15: 0000000000000000
Code: 87 80 0c 00 00 00 00 00 00 41 c7 87 20 03 00 00 00 00 00 00 48 c7 c7 18 d6 a2 87 31 c0 48 89 d6 4c 89 ea 4c 89 e1 e8 7b af 90 fe <0f> 0b 66 0f 1f 84 00 00 00 00 00 eb fe 48 8b 7d c8 e8 15 e3 0a 
RIP: __list_add_valid+0x275/0x450 lib/list_debug.c:23 RSP: ffff88016537f0c0
---[ end trace 365aec75f1dee5f1 ]---