------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 8073 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0
Modules linked in:
CPU: 0 UID: 0 PID: 8073 Comm: syz.0.1044 Not tainted 6.16.0-rc3-syzkaller-00159-g223e2288f4b8-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
Code: 00 00 e8 89 d2 fe fc 5b 41 5e c3 cc cc cc cc cc e8 7b d2 fe fc c6 05 7e 45 ca 0a 01 90 48 c7 c7 40 45 e2 8b e8 f7 7a c2 fc 90 <0f> 0b 90 90 eb d7 e8 5b d2 fe fc c6 05 5f 45 ca 0a 01 90 48 c7 c7
RSP: 0018:ffffc9000864fc88 EFLAGS: 00010246
RAX: 837e9d60caeb0200 RBX: 0000000000000002 RCX: ffff888023e13980
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc9000864fd90 R08: ffff88804b024293 R09: 1ffff11009604852
R10: dffffc0000000000 R11: ffffed1009604853 R12: 1ffff1100514e805
R13: 1ffff920010c9f9c R14: ffff8880279866c8 R15: dffffc0000000000
FS:  00007f70d91416c0(0000) GS:ffff8880b861d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f70d9140fc8 CR3: 00000001107e0000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ax25_setsockopt+0xabb/0xc20
 do_sock_setsockopt+0x25a/0x3e0
 __x64_sys_setsockopt+0x18b/0x220
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f70d838e929
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:00007f70d9141038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f70d85b5fa0 RCX: 00007f70d838e929
RDX: 0000000000000019 RSI: 0000000000000101 RDI: 000000000000000a
RBP: 00007f70d8410b39 R08: 0000000000000010 R09: 0000000000000000
R10: 00002000000001c0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f70d85b5fa0 R15: 00007ffc34bf2488
 </TASK>
