Subject: Re: [syzbot] [netfilter?] WARNING: ODEBUG bug in hash_netiface4_destroy

From: syzbot <[email-masked]>
Date: Fri, 02 Feb 2024 19:12:25 -0800

syzbot has found a reproducer for the following issue on:

HEAD commit:    6897cea71837 Merge tag 'for-6.8/dm-fixes' of git://git.ker..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1181d4ffe80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=457249c250b93697
dashboard link: https://syzkaller.appspot.com/bug?extid=52bbc0ad036f6f0d4a25
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=174bd5d3e80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16fcf5b0180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/002e2c38dde7/disk-6897cea7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/316b28b8e4a4/vmlinux-6897cea7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/35f7067d9e3f/bzImage-6897cea7.xz

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

------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff888018aee050 object type: timer_list hint: hash_netiface4_gc+0x0/0x570 net/netfilter/ipset/ip_set_hash_gen.h:445
WARNING: CPU: 1 PID: 5074 at lib/debugobjects.c:517 debug_print_object+0x17a/0x1f0 lib/debugobjects.c:514
Modules linked in:
CPU: 1 PID: 5074 Comm: syz-executor696 Not tainted 6.8.0-rc2-syzkaller-00251-g6897cea71837 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:debug_print_object+0x17a/0x1f0 lib/debugobjects.c:514
Code: e8 fb 03 4e fd 4c 8b 0b 48 c7 c7 a0 71 fe 8b 48 8b 74 24 08 48 89 ea 44 89 e1 4d 89 f8 ff 34 24 e8 9b f8 af fc 48 83 c4 08 90 <0f> 0b 90 90 ff 05 2c 09 de 0a 48 83 c4 10 5b 41 5c 41 5d 41 5e 41
RSP: 0018:ffffc900040cead8 EFLAGS: 00010286
RAX: 92d7284228c9b100 RBX: ffffffff8bac9720 RCX: ffff888026548000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff8bfe7320 R08: ffffffff81577992 R09: 1ffff92000819cac
R10: dffffc0000000000 R11: fffff52000819cad R12: 0000000000000000
R13: ffffffff8bfe7238 R14: dffffc0000000000 R15: ffff888018aee050
FS:  0000555555926380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000504 CR3: 000000002386a000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 __debug_check_no_obj_freed lib/debugobjects.c:989 [inline]
 debug_check_no_obj_freed+0x45b/0x580 lib/debugobjects.c:1019
 slab_free_hook mm/slub.c:2093 [inline]
 slab_free mm/slub.c:4299 [inline]
 kfree+0x110/0x380 mm/slub.c:4409
 hash_netiface4_destroy+0x297/0x2c0 net/netfilter/ipset/ip_set_hash_gen.h:460
 ip_set_create+0x13b6/0x1780 net/netfilter/ipset/ip_set_core.c:1157
 nfnetlink_rcv_msg+0xbee/0x1190 net/netfilter/nfnetlink.c:302
 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2543
 nfnetlink_rcv+0x294/0x2650 net/netfilter/nfnetlink.c:659
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x7ec/0x980 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x223/0x270 net/socket.c:745
 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
 ___sys_sendmsg net/socket.c:2638 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f7cfc8b0bb9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd4de24948 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7cfc8b0bb9
RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000004
RBP: 0000000000012024 R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd4de2495c
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>

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#syz test: git://repo/address.git branch-or-commit-hash
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