Subject: [syzbot] [netfilter?] WARNING in __nf_unregister_net_hook (6)

From: syzbot <[email-masked]>
Date: Tue, 17 Oct 2023 11:04:58 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    6465e260f487 Linux 6.6-rc3
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1376e3bc680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8d7d7928f78936aa
dashboard link: https://syzkaller.appspot.com/bug?extid=de4025c006ec68ac56fc
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17f218da680000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=149ff8c6680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/563852357aa6/disk-6465e260.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/df22793fe953/vmlinux-6465e260.xz
kernel image: https://storage.googleapis.com/syzbot-assets/84c2aad43ae3/bzImage-6465e260.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

------------[ cut here ]------------
hook not found, pf 2 num 1
WARNING: CPU: 1 PID: 5062 at net/netfilter/core.c:517 __nf_unregister_net_hook+0x1de/0x670 net/netfilter/core.c:517
Modules linked in:
CPU: 1 PID: 5062 Comm: syz-executor417 Not tainted 6.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
RIP: 0010:__nf_unregister_net_hook+0x1de/0x670 net/netfilter/core.c:517
Code: 14 02 4c 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 7a 04 00 00 8b 53 1c 48 c7 c7 c0 d4 a8 8b 8b 74 24 04 e8 b2 ce dc f8 <0f> 0b e9 ec 00 00 00 e8 46 a5 16 f9 48 89 e8 48 c1 e0 04 49 8d 7c
RSP: 0018:ffffc9000355f2b8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8880218dde00 RCX: 0000000000000000
RDX: ffff888019aee000 RSI: ffffffff814cf016 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff92611690
R13: ffff888016fff020 R14: ffff888016fff000 R15: ffff8880218dde1c
FS:  00007f76ca1526c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76ca1e86b8 CR3: 0000000020292000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 nf_unregister_net_hook+0xd5/0x110 net/netfilter/core.c:539
 __nf_tables_unregister_hook net/netfilter/nf_tables_api.c:361 [inline]
 __nf_tables_unregister_hook+0x1a0/0x220 net/netfilter/nf_tables_api.c:340
 nf_tables_unregister_hook net/netfilter/nf_tables_api.c:368 [inline]
 nf_tables_commit+0x410f/0x59f0 net/netfilter/nf_tables_api.c:9992
 nfnetlink_rcv_batch+0xf36/0x2500 net/netfilter/nfnetlink.c:569
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:639 [inline]
 nfnetlink_rcv+0x3bf/0x430 net/netfilter/nfnetlink.c:657
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:753
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2541
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2595
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f76ca192059
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f76ca152208 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f76ca21c3e8 RCX: 00007f76ca192059
RDX: 0000000000000000 RSI: 000000002000c2c0 RDI: 0000000000000004
RBP: 00007f76ca21c3e0 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000a00 R11: 0000000000000246 R12: 00007f76ca1e917c
R13: 0000000000000001 R14: 0000000000000008 R15: 0200000000000000
 </TASK>

---
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