Re: [syzbot] [net?] WARNING in nsim_udp_tunnel_set_port

[syzbot]

Hello,

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

------------[ cut here ]------------
entry already in use
WARNING: CPU: 0 PID: 6740 at drivers/net/netdevsim/udp_tunnels.c:26 nsim_udp_tunnel_set_port+0x2d3/0x390 drivers/net/netdevsim/udp_tunnels.c:26
Modules linked in:
CPU: 0 UID: 0 PID: 6740 Comm: syz.2.25 Not tainted 6.13.0-rc7-syzkaller-gcf33d96f5090 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:nsim_udp_tunnel_set_port+0x2d3/0x390 drivers/net/netdevsim/udp_tunnels.c:26
Code: c3 cc cc cc cc e8 dd ed c9 fa 44 89 f7 e8 95 88 b7 fa e9 ee fd ff ff e8 cb ed c9 fa 90 48 c7 c7 80 96 2a 8c e8 ae b5 8a fa 90 <0f> 0b 90 90 4c 8d 73 04 41 bf f0 ff ff ff e9 fa fe ff ff e8 15 5e
RSP: 0018:ffffc90003117ab8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffc90003117bb0 RCX: ffffffff815a17c9
RDX: ffff8880273a9e00 RSI: ffffffff815a17d6 RDI: 0000000000000001
RBP: ffff88802508c000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000017c10002 R15: 0000000000000000
FS:  00007fd6e91046c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f70aa746d38 CR3: 000000003328e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:225 [inline]
 udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:246 [inline]
 __udp_tunnel_nic_device_sync.part.0+0x935/0xed0 net/ipv4/udp_tunnel_nic.c:289
 __udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:283 [inline]
 __udp_tunnel_nic_reset_ntf+0x3c1/0x520 net/ipv4/udp_tunnel_nic.c:581
 udp_tunnel_nic_reset_ntf include/net/udp_tunnel.h:377 [inline]
 nsim_udp_tunnels_info_reset_write+0xc2/0x110 drivers/net/netdevsim/udp_tunnels.c:117
 full_proxy_write+0xfd/0x1b0 fs/debugfs/file.c:369
 vfs_write+0x24c/0x1150 fs/read_write.c:677
 ksys_write+0x12b/0x250 fs/read_write.c:731
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd6e8385d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd6e9104038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd6e8575fa0 RCX: 00007fd6e8385d29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fd6e8401b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd6e8575fa0 R15: 00007ffd899920e8
 </TASK>


Tested on:

commit:         cf33d96f Merge git://git.kernel.org/pub/scm/linux/kern..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git main
console output: https://syzkaller.appspot.com/x/log.txt?x=142f3618580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=3eff53fbe4c843d4
dashboard link: https://syzkaller.appspot.com/bug?extid=2e5de9e3ab986b71d2bf
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.