bpfilter: read fail -512
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 0 PID: 4583 Comm: syz-executor3 Not tainted 4.17.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:file_write_hint include/linux/fs.h:1932 [inline]
RIP: 0010:init_sync_kiocb include/linux/fs.h:1942 [inline]
RIP: 0010:new_sync_write fs/read_write.c:470 [inline]
RIP: 0010:__vfs_write+0x4a6/0x960 fs/read_write.c:487
Code: c1 ea 03 80 3c 02 00 0f 85 1b 04 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 63 20 49 8d bc 24 c8 00 00 00 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e ec 02 00 00 41 8b 84 24 c8 00 
RSP: 0018:ffff8801976b7850 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8801d2185c80 RCX: ffffffff81c0d6fb
RDX: 0000000000000019 RSI: ffffffff81c0d70a RDI: 00000000000000c8
RBP: ffff8801976b79c8 R08: ffff8801976ae780 R09: fffffbfff130c5d9
R10: ffff8801976b7a10 R11: ffffffff89862ecb R12: 0000000000000000
R13: ffff8801976b79a0 R14: 0000000000000000 R15: ffff8801976b7a88
FS:  0000000002753940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc26cc9d638 CR3: 00000001974ff000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __kernel_write+0x10c/0x380 fs/read_write.c:506
 __bpfilter_process_sockopt+0x1d8/0x35b net/bpfilter/bpfilter_kern.c:66
 bpfilter_mbox_request+0x4d/0xb0 net/ipv4/bpfilter/sockopt.c:25
 bpfilter_ip_get_sockopt+0x6b/0x90 net/ipv4/bpfilter/sockopt.c:42
 ip_getsockopt+0x238/0x2a0 net/ipv4/ip_sockglue.c:1563
 tcp_getsockopt+0x93/0xe0 net/ipv4/tcp.c:3532
 sock_common_getsockopt+0x9a/0xe0 net/core/sock.c:3012
 __sys_getsockopt+0x1a5/0x370 net/socket.c:1972
 __do_sys_getsockopt net/socket.c:1983 [inline]
 __se_sys_getsockopt net/socket.c:1980 [inline]
 __x64_sys_getsockopt+0xbe/0x150 net/socket.c:1980
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4584ea
Code: b8 34 01 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 1d 8f fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 fa 8e fb ff c3 66 0f 1f 84 00 00 00 00 00 
RSP: 002b:0000000000a3e328 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 0000000000a3e350 RCX: 00000000004584ea
RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000013
RBP: 0000000000706f20 R08: 0000000000a3e34c R09: 0000000000004000
R10: 0000000000a3e350 R11: 0000000000000246 R12: 0000000000000013
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000705420
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace 983bd990e18402eb ]---
RIP: 0010:file_write_hint include/linux/fs.h:1932 [inline]
RIP: 0010:init_sync_kiocb include/linux/fs.h:1942 [inline]
RIP: 0010:new_sync_write fs/read_write.c:470 [inline]
RIP: 0010:__vfs_write+0x4a6/0x960 fs/read_write.c:487
Code: c1 ea 03 80 3c 02 00 0f 85 1b 04 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 63 20 49 8d bc 24 c8 00 00 00 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e ec 02 00 00 41 8b 84 24 c8 00 
RSP: 0018:ffff8801976b7850 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8801d2185c80 RCX: ffffffff81c0d6fb
RDX: 0000000000000019 RSI: ffffffff81c0d70a RDI: 00000000000000c8
RBP: ffff8801976b79c8 R08: ffff8801976ae780 R09: fffffbfff130c5d9
R10: ffff8801976b7a10 R11: ffffffff89862ecb R12: 0000000000000000
R13: ffff8801976b79a0 R14: 0000000000000000 R15: ffff8801976b7a88
FS:  0000000002753940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc26cc9d638 CR3: 00000001974ff000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400