BUG: corrupted list in end_requests

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    1236568ee3cb Merge tag 'gpio-v4.18-3' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10bf0c9c400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=152cb8ccd35b1f70
dashboard link: https://syzkaller.appspot.com/bug?extid=0d2dc8aade663e725664
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+0d2dc8aade663e725664@xxxxxxxxxxxxxxxxxxxxxxxxx

list_del corruption. prev->next should be ffff8801ae811e00, but was  
ffff8801b5477738
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:53!
invalid opcode: 0000 [#1] SMP KASAN
CPU: 0 PID: 17968 Comm: syz-executor0 Not tainted 4.18.0-rc8+ #180
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:__list_del_entry_valid.cold.1+0x48/0x58 lib/list_debug.c:51
Code: 68 3a 87 e8 36 92 02 fe 0f 0b 48 89 de 48 c7 c7 e0 69 3a 87 e8 25 92  
02 fe 0f 0b 48 89 de 48 c7 c7 80 69 3a 87 e8 14 92 02 fe <0f> 0b 90 90 90  
90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57
RSP: 0018:ffff8801b5477490 EFLAGS: 00010282
RAX: 0000000000000054 RBX: ffff8801ae811e00 RCX: ffffc90002e24000
RDX: 0000000000000000 RSI: ffffffff81632481 RDI: 0000000000000001
RBP: ffff8801b54774a8 R08: ffff88019a1760c0 R09: ffffed003b604fc0
R10: ffffed003b604fc0 R11: ffff8801db027e07 R12: ffff8801ae811e00
R13: ffff8801b5477738 R14: ffff8801ae811e00 R15: dffffc0000000000
FS:  00007f8f17566700(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000704071 CR3: 00000001ac63b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __list_del_entry include/linux/list.h:117 [inline]
 list_del_init include/linux/list.h:159 [inline]
 end_requests+0x180/0x460 fs/fuse/dev.c:2044
 fuse_abort_conn+0xf9c/0x1580 fs/fuse/dev.c:2138
 fuse_put_super+0x123/0x440 fs/fuse/inode.c:396
 generic_shutdown_super+0x1bf/0x530 fs/super.c:453
 kill_anon_super+0x3c/0x50 fs/super.c:1046
 fuse_kill_sb_anon+0x90/0xb0 fs/fuse/inode.c:1223
 deactivate_locked_super+0x97/0x100 fs/super.c:326
 deactivate_super+0x193/0x1c0 fs/super.c:357
 cleanup_mnt+0xbf/0x160 fs/namespace.c:1174
 __cleanup_mnt+0x16/0x20 fs/namespace.c:1181
 task_work_run+0x1ec/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:192 [inline]
 exit_to_usermode_loop+0x313/0x370 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x456cb9
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7  
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff  
ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8f17565c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f8f175666d4 RCX: 0000000000456cb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100
RBP: 00000000009301e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d6360 R14: 00000000004c9ab8 R15: 0000000000000002
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace 060c5491c93d7527 ]---
RIP: 0010:__list_del_entry_valid.cold.1+0x48/0x58 lib/list_debug.c:51
Code: 68 3a 87 e8 36 92 02 fe 0f 0b 48 89 de 48 c7 c7 e0 69 3a 87 e8 25 92  
02 fe 0f 0b 48 89 de 48 c7 c7 80 69 3a 87 e8 14 92 02 fe <0f> 0b 90 90 90  
90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57
RSP: 0018:ffff8801b5477490 EFLAGS: 00010282
RAX: 0000000000000054 RBX: ffff8801ae811e00 RCX: ffffc90002e24000
RDX: 0000000000000000 RSI: ffffffff81632481 RDI: 0000000000000001
RBP: ffff8801b54774a8 R08: ffff88019a1760c0 R09: ffffed003b604fc0
R10: ffffed003b604fc0 R11: ffff8801db027e07 R12: ffff8801ae811e00
R13: ffff8801b5477738 R14: ffff8801ae811e00 R15: dffffc0000000000
FS:  00007f8f17566700(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000704071 CR3: 00000001ac63b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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