Re: [syzbot] [net?] KASAN: slab-use-after-free Write in __xfrm_state_delete

[syzbot <syzbot+a25ee9d20d31e483ba7b@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in __xfrm_state_destroy

------------[ cut here ]------------
WARNING: CPU: 1 PID: 36 at net/xfrm/xfrm_state.c:801 __xfrm_state_destroy+0x15f/0x190 net/xfrm/xfrm_state.c:801
Modules linked in:
CPU: 1 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: netns cleanup_net
RIP: 0010:__xfrm_state_destroy+0x15f/0x190 net/xfrm/xfrm_state.c:801
Code: 48 c7 c2 00 34 63 8f 5b 41 5c 41 5d 41 5e 41 5f 5d e9 25 89 69 f7 e8 70 33 9f f7 90 0f 0b 90 e9 00 ff ff ff e8 62 33 9f f7 90 <0f> 0b 90 e9 20 ff ff ff 44 89 f1 80 e1 07 38 c1 0f 8c c6 fe ff ff
RSP: 0018:ffffc90000ac77f0 EFLAGS: 00010293
RAX: ffffffff8a2077ce RBX: ffff88807cc9c008 RCX: ffff8881404e1e00
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005
RBP: 0000000000000005 R08: ffff88807cc9c06b R09: 1ffff1100f99380d
R10: dffffc0000000000 R11: ffffed100f99380e R12: dffffc0000000000
R13: 1ffff1100f993802 R14: ffff88807cc9c010 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055eb8c9a1008 CR3: 0000000027f28000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 xfrm_state_put include/net/xfrm.h:928 [inline]
 xfrm_state_flush+0x4fd/0x6c0 net/xfrm/xfrm_state.c:945
 xfrm6_tunnel_net_exit+0x3c/0x100 net/ipv6/xfrm6_tunnel.c:337
 ops_exit_list net/core/net_namespace.c:198 [inline]
 ops_undo_list+0x49a/0x990 net/core/net_namespace.c:251
 cleanup_net+0x4c5/0x800 net/core/net_namespace.c:682
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>


Tested on:

commit:         df534e75 net: phylink: remove stale an_enabled from doc
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=13d69c42580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=67b99ceb67d33475
dashboard link: https://syzkaller.appspot.com/bug?extid=a25ee9d20d31e483ba7b
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10aaeef0580000