------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 4267 at lib/refcount.c:25 refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 1 PID: 4267 Comm: syz-executor Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25
Code: 09 01 48 c7 c7 a0 d2 be 8a e8 ad 30 45 fd 0f 0b eb e0 e8 f4 1d 79 fd c6 05 fa 72 e2 09 01 48 c7 c7 e0 d1 be 8a e8 91 30 45 fd <0f> 0b eb c4 e8 d8 1d 79 fd c6 05 df 72 e2 09 01 48 c7 c7 40 d2 be
RSP: 0018:ffffc900001e0828 EFLAGS: 00010246
RAX: 6a8129efcef36800 RBX: 0000000000000002 RCX: ffff888025065940
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc900001e0990 R08: dffffc0000000000 R09: fffff5200003c095
R10: fffff5200003c095 R11: 1ffff9200003c094 R12: ffff88801e340000
R13: dffffc0000000000 R14: 0000000000000002 R15: ffff88807800f848
FS:  0000555582b42500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa5ea6e56c0 CR3: 000000005b2c1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __refcount_add include/linux/refcount.h:-1 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 get_net include/net/net_namespace.h:257 [inline]
 tipc_aead_encrypt net/tipc/crypto.c:821 [inline]
 tipc_crypto_xmit+0x17a9/0x2300 net/tipc/crypto.c:1761
 tipc_bearer_xmit_skb+0x242/0x3f0 net/tipc/bearer.c:574
 tipc_disc_timeout+0x568/0x6b0 net/tipc/discover.c:338
 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:check_kcov_mode kernel/kcov.c:193 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x32/0x80 kernel/kcov.c:320
Code: e4 94 81 7e 65 8b 15 e5 94 81 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 16 00 00 00 74 4e 8b 91 f8 15 00 00 <83> fa 03 75 43 48 8b 91 00 16 00 00 44 8b 89 fc 15 00 00 49 c1 e1
RSP: 0018:ffffc90003ce7558 EFLAGS: 00000246
RAX: ffffffff81be401a RBX: 0000000000000000 RCX: ffff888025065940
RDX: 0000000000000000 RSI: 0000000000000028 RDI: 0000000000000020
RBP: ffffc90003ce7850 R08: dffffc0000000000 R09: fffff940002e9e99
R10: fffff940002e9e99 R11: 1ffffd40002e9e98 R12: 1ffffd40002e9e99
R13: ffffea000174f4c0 R14: 0000000000000028 R15: ffffea000174f4c0
 is_cow_mapping include/linux/mm.h:1267 [inline]
 copy_present_pte mm/memory.c:983 [inline]
 copy_pte_range mm/memory.c:1091 [inline]
 copy_pmd_range mm/memory.c:1177 [inline]
 copy_pud_range mm/memory.c:1214 [inline]
 copy_p4d_range mm/memory.c:1238 [inline]
 copy_page_range+0x16fa/0x39e0 mm/memory.c:1336
 dup_mmap kernel/fork.c:697 [inline]
 dup_mm kernel/fork.c:1541 [inline]
 copy_mm+0xde1/0x15c0 kernel/fork.c:1590
 copy_process+0x1953/0x4020 kernel/fork.c:2351
 kernel_clone+0x225/0x8b0 kernel/fork.c:2757
 __do_sys_clone kernel/fork.c:2898 [inline]
 __se_sys_clone kernel/fork.c:2882 [inline]
 __x64_sys_clone+0x17c/0x1d0 kernel/fork.c:2882
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa5e9985193
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffd10414188 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa5e9985193
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555582b427d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 0000000000065c96 R15: 00007ffd10414320
 </TASK>
----------------
Code disassembly (best guess):
   0:	e4 94                	in     $0x94,%al
   2:	81 7e 65 8b 15 e5 94 	cmpl   $0x94e5158b,0x65(%rsi)
   9:	81 7e 81 e2 00 01 ff 	cmpl   $0xff0100e2,-0x7f(%rsi)
  10:	00 74 11 81          	add    %dh,-0x7f(%rcx,%rdx,1)
  14:	fa                   	cli
  15:	00 01                	add    %al,(%rcx)
  17:	00 00                	add    %al,(%rax)
  19:	75 57                	jne    0x72
  1b:	83 b9 1c 16 00 00 00 	cmpl   $0x0,0x161c(%rcx)
  22:	74 4e                	je     0x72
  24:	8b 91 f8 15 00 00    	mov    0x15f8(%rcx),%edx
* 2a:	83 fa 03             	cmp    $0x3,%edx <-- trapping instruction
  2d:	75 43                	jne    0x72
  2f:	48 8b 91 00 16 00 00 	mov    0x1600(%rcx),%rdx
  36:	44 8b 89 fc 15 00 00 	mov    0x15fc(%rcx),%r9d
  3d:	49                   	rex.WB
  3e:	c1                   	.byte 0xc1
  3f:	e1                   	.byte 0xe1