general protection fault in sock_do_ioctl

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    62c8a069b510 net: mvpp2: Add missing VLAN tag detection
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=10ad5827800000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b632d8e2c2ab2c1
dashboard link: https://syzkaller.appspot.com/bug?extid=09b980aff7b322aac68d
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+09b980aff7b322aac68d@xxxxxxxxxxxxxxxxxxxxxxxxx

 __sys_sendmsg+0x115/0x270 net/socket.c:2155
kasan: CONFIG_KASAN_INLINE enabled
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2162
kasan: GPF could be caused by NULL-ptr deref or user memory access
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
Modules linked in:
RIP: 0033:0x455a09
RSP: 002b:00007f7f8526bc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
CPU: 0 PID: 8176 Comm: syz-executor2 Not tainted 4.17.0-rc4+ #53
RAX: ffffffffffffffda RBX: 00007f7f8526c6d4 RCX: 0000000000455a09
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RDX: 0000000000000000 RSI: 00000000200019c0 RDI: 0000000000000013
RIP: 0010:smc_tx_prepared_sends net/smc/smc_tx.h:27 [inline]
RIP: 0010:smc_ioctl+0x6db/0x9f0 net/smc/af_smc.c:1506
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
RSP: 0018:ffff8801afe4f770 EFLAGS: 00010202
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000014
R13: 000000000000059b R14: 00000000006fc728 R15: 0000000000000005
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: 0000000000000004 RSI: 1ffff10035fc9f0d RDI: 0000000000000020
RBP: ffff8801afe4f9d0 R08: ffffed0035fc9f0e R09: ffffed0035fc9f0d
R10: ffffed0035fc9f0d R11: ffff8801afe4f86f R12: 1ffff10035fc9ef1
R13: 00000000200003c0 R14: ffff8801afe4f868 R15: ffff8801afe4f828
FS:  00007f6710832700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000007270dc CR3: 00000001c83ae000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sock_do_ioctl+0xe4/0x3e0 net/socket.c:957
 sock_ioctl+0x30d/0x680 net/socket.c:1081
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 8189 Comm: syz-executor5 Not tainted 4.17.0-rc4+ #53
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
Call Trace:
RIP: 0033:0x455a09
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
RSP: 002b:00007f6710831c68 EFLAGS: 00000246
 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f67108326d4 RCX: 0000000000455a09
 fail_dump lib/fault-inject.c:51 [inline]
 should_fail.cold.4+0xa/0x1a lib/fault-inject.c:149
RDX: 00000000200003c0 RSI: 000000000000894b RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000044c R14: 00000000006fa7c0 R15: 0000000000000000
Code:
f8
48
c1
e8
03
80
3c
10
00
0f
85
ed
01
00
00
48
8b
9b
 __should_failslab+0x124/0x180 mm/failslab.c:32
90
 should_failslab+0x9/0x14 mm/slab_common.c:1522
04
 slab_pre_alloc_hook mm/slab.h:423 [inline]
 slab_alloc mm/slab.c:3378 [inline]
 kmem_cache_alloc+0x47/0x760 mm/slab.c:3552
00
00
48
 kmem_cache_zalloc include/linux/slab.h:691 [inline]
 fill_pool lib/debugobjects.c:134 [inline]
 __debug_object_init+0xbc0/0x12c0 lib/debugobjects.c:377
b8
00
00
00
00
00 fc
ff
df
48
8d
7b
20
48
89
fa
48
c1
ea
03
<0f>
b6
04
02
84
c0
74
08
3c
03
 debug_object_init+0x16/0x20 lib/debugobjects.c:429
0f
 debug_timer_init kernel/time/timer.c:704 [inline]
 debug_init kernel/time/timer.c:757 [inline]
 init_timer_key+0xa1/0x470 kernel/time/timer.c:806
8e
b7
01
00
00
 sctp_association_init net/sctp/associola.c:152 [inline]
 sctp_association_new+0xa90/0x2170 net/sctp/associola.c:312
8b
43
20
49
8d
RIP: smc_tx_prepared_sends net/smc/smc_tx.h:27 [inline] RSP:  
ffff8801afe4f770
RIP: smc_ioctl+0x6db/0x9f0 net/smc/af_smc.c:1506 RSP: ffff8801afe4f770
---[ end trace ed404e46621ff58c ]---


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