Subject: general protection fault in hash_net4_uadt

From: syzbot <[email-masked]>
Date: Wed, 08 Jan 2020 01:14:12 -0800

Hello,

syzbot found the following crash on:

HEAD commit:    c101fffc Merge tag 'mlx5-fixes-2020-01-06' of git://git.ke..
git tree:       net
console output: https://syzkaller.appspot.com/x/log.txt?x=1452e656e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f2f3ef188b7e16cf
dashboard link: https://syzkaller.appspot.com/bug?extid=b8e32edde51fdcc8c2c4
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17ef2459e00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=113b9459e00000

The bug was bisected to:

commit 23c42a403a9cfdbad6004a556c927be7dd61a8ee
Author: Jozsef Kadlecsik <[email-masked]>
Date:   Sat Oct 27 13:07:40 2018 +0000

     netfilter: ipset: Introduction of new commands and protocol version 7

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=146e1469e00000
final crash:    https://syzkaller.appspot.com/x/report.txt?x=166e1469e00000
console output: https://syzkaller.appspot.com/x/log.txt?x=126e1469e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email-masked]
Fixes: 23c42a403a9c ("netfilter: ipset: Introduction of new commands and  
protocol version 7")

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: 9328 Comm: syz-executor866 Not tainted 5.5.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:hash_net4_uadt+0x200/0x940  
net/netfilter/ipset/ip_set_hash_net.c:146
Code: 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 92 06 00 00 4c 89  
e2 45 8b 6d 04 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 14 02 4c  
89 e0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 57
RSP: 0018:ffffc90002007190 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffffc90002007320 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff86801a0d RDI: ffff88809aba2048
RBP: ffffc900020072b8 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed1015d0703c R11: ffff8880ae8381e3 R12: 0000000000000000
R13: 0000000009000000 R14: ffff8880a485b000 R15: 0000000000000002
FS:  0000000001f44880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000446 CR3: 00000000a8e94000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  ip_set_utest+0x55b/0x890 net/netfilter/ipset/ip_set_core.c:1867
  nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229
  netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
  nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563
  netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
  netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328
  netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:639 [inline]
  sock_sendmsg+0xd7/0x130 net/socket.c:659
  ____sys_sendmsg+0x753/0x880 net/socket.c:2330
  ___sys_sendmsg+0x100/0x170 net/socket.c:2384
  __sys_sendmsg+0x105/0x1d0 net/socket.c:2417
  __do_sys_sendmsg net/socket.c:2426 [inline]
  __se_sys_sendmsg net/socket.c:2424 [inline]
  __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424
  do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440669
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffde779c858 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440669
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000004
RBP: 00000000006ca018 R08: 0000000000000048 R09: 00000000004002c8
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000401ef0
R13: 0000000000401f80 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace e8c4a3e1455d3dc0 ]---
RIP: 0010:hash_net4_uadt+0x200/0x940  
net/netfilter/ipset/ip_set_hash_net.c:146
Code: 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 92 06 00 00 4c 89  
e2 45 8b 6d 04 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 14 02 4c  
89 e0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 57
RSP: 0018:ffffc90002007190 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffffc90002007320 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff86801a0d RDI: ffff88809aba2048
RBP: ffffc900020072b8 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed1015d0703c R11: ffff8880ae8381e3 R12: 0000000000000000
R13: 0000000009000000 R14: ffff8880a485b000 R15: 0000000000000002
FS:  0000000001f44880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000446 CR3: 00000000a8e94000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

---
This bug is generated by a bot. It may contain errors.
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection
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