[syzbot] [net?] WARNING in unreserve_psock

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    c29e012eae29 selftests: forwarding: Fix layer 2 miss test ..
git tree:       net-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=14505343280000
kernel config:  https://syzkaller.appspot.com/x/.config?x=526f919910d4a671
dashboard link: https://syzkaller.appspot.com/bug?extid=dd1339599f1840e4cc65
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=170f2663280000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12f1c5e7280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/12ab2dfeec70/disk-c29e012e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/424354551939/vmlinux-c29e012e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/40982e9df534/bzImage-c29e012e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dd1339599f1840e4cc65@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5007 at net/kcm/kcmsock.c:533 unreserve_psock+0x2e1/0x6e0 net/kcm/kcmsock.c:533
Modules linked in:
CPU: 0 PID: 5007 Comm: syz-executor222 Not tainted 6.4.0-rc5-syzkaller-01194-gc29e012eae29 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:unreserve_psock+0x2e1/0x6e0 net/kcm/kcmsock.c:533
Code: 3c f8 48 89 ef e8 df b1 ff ff 4c 89 f7 e8 e7 f5 cd 00 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f e9 c4 f2 3c f8 e8 bf f2 3c f8 <0f> 0b 4c 89 f7 e8 c5 f5 cd 00 eb dc e8 ae f2 3c f8 0f 0b e9 f0 fe
RSP: 0018:ffffc90003a9f6a0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888077f60000 RCX: 0000000000000000
RDX: ffff8880284d3b80 RSI: ffffffff89475391 RDI: ffffc90003a9f630
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000003
R10: fffff52000753ec6 R11: 0000000000000005 R12: ffff88802cfd8000
R13: ffff888077f60000 R14: ffff88802cfd81c0 R15: ffff888077f60598
FS:  000055555562f300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200006c8 CR3: 0000000025a48000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kcm_write_msgs+0x571/0x14b0 net/kcm/kcmsock.c:699
 kcm_sendmsg+0x1fe1/0x2720 net/kcm/kcmsock.c:903
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:747
 ____sys_sendmsg+0x344/0x920 net/socket.c:2493
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2547
 __sys_sendmmsg+0x18f/0x460 net/socket.c:2633
 __do_sys_sendmmsg net/socket.c:2662 [inline]
 __se_sys_sendmmsg net/socket.c:2659 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2659
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7efed1630b39
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff10fc2e08 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007efed1630b39
RDX: 0000000000000001 RSI: 00000000200006c0 RDI: 0000000000000003
RBP: 00007efed15f4ce0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007efed15f4d70
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


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