list_add corruption. next->prev should be prev (ffff88021fffab10), but was ffffea0007658de0. (next=ffffea00076195a0).
------------[ 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: 7103 Comm: syz-executor6 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:ffff880138f1f050 EFLAGS: 00010082
RAX: 0000000000000075 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88021fd36eec
RBP: ffff880138f1f0b8 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea00076195a0
R13: ffffea0007658de0 R14: 0000000000000000 R15: ffffffff8b58b000
FS:  00007fbe58f57700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe03aba0ea0 CR3: 000000014443e000 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_pcppages_bulk+0x1019/0x12c0 mm/page_alloc.c:1160
 free_unref_page_commit+0x358/0x4d0 mm/page_alloc.c:2800
 free_unref_page mm/page_alloc.c:2816 [inline]
 __free_pages+0x1b9/0x240 mm/page_alloc.c:4440
 kmsan_free_page+0x197/0x2e0 mm/kmsan/kmsan.c:955
 free_pages_prepare mm/page_alloc.c:996 [inline]
 free_pcp_prepare mm/page_alloc.c:1060 [inline]
 free_unref_page_prepare+0x22f/0x620 mm/page_alloc.c:2763
 free_unref_page mm/page_alloc.c:2812 [inline]
 __free_pages mm/page_alloc.c:4440 [inline]
 free_pages+0x230/0x320 mm/page_alloc.c:4452
 arch_tlb_finish_mmu mm/memory.c:290 [inline]
 tlb_finish_mmu+0x3f7/0x5c0 mm/memory.c:433
 exit_mmap+0x514/0x970 mm/mmap.c:3107
 __mmput+0x158/0x600 kernel/fork.c:962
 mmput+0xab/0xf0 kernel/fork.c:983
 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+0xfcb/0x1f40 kernel/signal.c:2482
 do_signal+0xb8/0x1cf0 arch/x86/kernel/signal.c:810
 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+0x1af/0x230 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a09
RSP: 002b:00007fbe58f56ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000072bf78 RCX: 0000000000455a09
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000072bf78
RBP: 000000000072bf78 R08: 0000000000000000 R09: 000000000072bf50
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000a3e81f R14: 00007fbe58f579c0 R15: 0000000000000001
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: ffff880138f1f050
---[ end trace 6dd64c3c368b1254 ]---