kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 22853 Comm: syz-executor5 Not tainted 4.19.0-rc6-next-20181005+ #88
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
kobject: 'loop4' (00000000275f6994): kobject_uevent_env
RIP: 0010:do_fault mm/memory.c:3524 [inline]
RIP: 0010:handle_pte_fault mm/memory.c:3762 [inline]
RIP: 0010:__handle_mm_fault+0x2d72/0x55c0 mm/memory.c:3886
Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 87 20 00 00 49 8b 9c 24 b0 fe ff ff 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 57 20 00 00 48 8b 1b 31 ff 48 83 e3 9f 48 89 de
RSP: 0018:ffff880175de6a08 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8160f791
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff880175de6b40
RBP: ffff880175de6cb8 R08: ffffed0030683f56 R09: ffffed0030683f55
R10: ffffed0030683f55 R11: ffff88018341faab R12: ffff880175de6c90
R13: ffff8801835b8800 R14: ffff88018d4390d0 R15: 0000000000000067
FS:  00007ff6f6587700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2c227000 CR3: 00000001c18ec000 CR4: 00000000001406f0
kobject: 'loop4' (00000000275f6994): fill_kobj_path: path = '/devices/virtual/block/loop4'
Call Trace:
 handle_mm_fault+0x54f/0xc70 mm/memory.c:3923
 faultin_page mm/gup.c:518 [inline]
 __get_user_pages+0x806/0x1b30 mm/gup.c:718
 __get_user_pages_locked mm/gup.c:889 [inline]
 get_user_pages_unlocked+0x2fc/0x5d0 mm/gup.c:1012
 get_user_pages_fast+0x322/0x450 mm/gup.c:1862
 iov_iter_get_pages+0x2c9/0x11e0 lib/iov_iter.c:1198
 __zerocopy_sg_from_iter+0x240/0xb80 net/core/datagram.c:596
 skb_zerocopy_iter_stream+0x24f/0x7d0 net/core/skbuff.c:1122
 tcp_sendmsg_locked+0x8cc/0x3f90 net/ipv4/tcp.c:1355
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1443
 inet_sendmsg+0x19c/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:632
 __sys_sendto+0x3d7/0x670 net/socket.c:1789
 __do_sys_sendto net/socket.c:1801 [inline]
 __se_sys_sendto net/socket.c:1797 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 1d 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff6f6586c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457579
RDX: fffffffffffffee3 RSI: 0000000020000b40 RDI: 0000000000000004
RBP: 000000000072bf00 R08: 0000000000000000 R09: ffffffffffffff61
R10: 00000000040000cb R11: 0000000000000246 R12: 00007ff6f65876d4
R13: 00000000004c3929 R14: 00000000004d57c0 R15: 00000000ffffffff
Modules linked in:
---[ end trace b7402b3b5ac99201 ]---
RIP: 0010:do_fault mm/memory.c:3524 [inline]
RIP: 0010:handle_pte_fault mm/memory.c:3762 [inline]
RIP: 0010:__handle_mm_fault+0x2d72/0x55c0 mm/memory.c:3886
Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 87 20 00 00 49 8b 9c 24 b0 fe ff ff 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 57 20 00 00 48 8b 1b 31 ff 48 83 e3 9f 48 89 de
RSP: 0018:ffff880175de6a08 EFLAGS: 00010246
cgroup: fork rejected by pids controller in 
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8160f791
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff880175de6b40
RBP: ffff880175de6cb8 R08: ffffed0030683f56 R09: ffffed0030683f55
R10: ffffed0030683f55 R11: ffff88018341faab R12: ffff880175de6c90
R13: ffff8801835b8800 R14: ffff88018d4390d0 R15: 0000000000000067
/syz0
FS:  00007ff6f6587700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2c227000 CR3: 00000001c18ec000 CR4: 00000000001406f0