BUG: corrupted list in rdma_listen

[syzbot]

Hello,

syzbot hit the following crash on upstream commit
bcfc1f4554662d8f2429ac8bd96064a59c149754 (Sat Mar 24 16:50:12 2018 +0000)
Merge tag 'pinctrl-v4.16-3' of  
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
syzbot dashboard link:  
https://syzkaller.appspot.com/bug?extid=8458d13b13562abf6b77

So far this crash happened 3 times on upstream.
Unfortunately, I don't have any reproducer for this crash yet.
Raw console output:  
https://syzkaller.appspot.com/x/log.txt?id=5502346817699840
Kernel config:  
https://syzkaller.appspot.com/x/.config?id=-5034017172441945317
compiler: gcc (GCC) 7.1.1 20170620

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Reported-by: syzbot+8458d13b13562abf6b77@xxxxxxxxxxxxxxxxxxxxxxxxx
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list_add corruption. prev->next should be next (00000000bbe7894a), but  
was           (null). (prev=0000000053f15260).
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:28!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 31373 Comm: syz-executor1 Not tainted 4.16.0-rc6+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:__list_add_valid+0x8f/0xd0 lib/list_debug.c:26
RSP: 0018:ffff880188f87970 EFLAGS: 00010282
RAX: 0000000000000075 RBX: ffffffff87449fe0 RCX: 0000000000000000
RDX: 0000000000000075 RSI: ffffc900075c8000 RDI: ffffed00311f0f22
RBP: ffff880188f87988 R08: 1ffff100311f0e7a R09: 0000000000000000
R10: ffff880188f87988 R11: 0000000000000000 R12: ffff88018c479898
R13: ffff88018c479898 R14: ffff8801d94baad8 R15: 0000000000000400
FS:  00007f755bcca700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000725934 CR3: 00000001872ec001 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __list_add include/linux/list.h:60 [inline]
 list_add_tail include/linux/list.h:93 [inline]
 cma_listen_on_all drivers/infiniband/core/cma.c:2309 [inline]
 rdma_listen+0x581/0x8e0 drivers/infiniband/core/cma.c:3333
 ucma_listen+0x172/0x1f0 drivers/infiniband/core/ucma.c:1074
 ucma_write+0x2d6/0x3d0 drivers/infiniband/core/ucma.c:1649
 __vfs_write+0xef/0x970 fs/read_write.c:480
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x454879
RSP: 002b:00007f755bcc9c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f755bcca6d4 RCX: 0000000000454879
RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000683 R14: 00000000006face8 R15: 0000000000000000
Code: 00 00 00 5b 41 5c 5d c3 48 89 d9 48 c7 c7 60 7e 40 86 e8 ad e0 fb fe  
0f 0b 48 89 f1 48 c7 c7 20 7f 40 86 48 89 de e8 99 e0 fb fe <0f> 0b 48 89  
f2 48 89 d9 4c 89 e6 48 c7 c7 a0 7f 40 86 e8 82 e0
RIP: __list_add_valid+0x8f/0xd0 lib/list_debug.c:26 RSP: ffff880188f87970
---[ end trace fe3987c6813eeb9c ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..


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