------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 7308 at lib/refcount.c:25 refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25 Modules linked in: CPU: 1 PID: 7308 Comm: syz.5.666 Not tainted 5.15.185-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 40 6b 59 8a e8 dd 27 bb 05 0f 0b eb e0 e8 04 42 9c fd c6 05 ae 8f 79 09 01 48 c7 c7 80 6a 59 8a e8 c1 27 bb 05 <0f> 0b eb c4 e8 e8 41 9c fd c6 05 93 8f 79 09 01 48 c7 c7 e0 6a 59 RSP: 0018:ffffc90000dd06a8 EFLAGS: 00010246 RAX: 6b58c3974ac3ea00 RBX: 0000000000000002 RCX: ffff888027375940 RDX: 0000000000000100 RSI: 0000000080000100 RDI: 0000000000000000 RBP: ffffc90000dd0808 R08: dffffc0000000000 R09: fffff520001ba039 R10: fffff520001ba039 R11: 1ffff920001ba038 R12: ffff88807aea0000 R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000000 FS: 00007f59a6aab6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000266030 CR3: 000000004d8e7000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __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:252 [inline] tipc_aead_encrypt net/tipc/crypto.c:832 [inline] tipc_crypto_xmit+0x1949/0x2560 net/tipc/crypto.c:1772 tipc_crypto_clone_msg+0x91/0x160 net/tipc/crypto.c:1667 tipc_crypto_xmit+0x1ac5/0x2560 net/tipc/crypto.c:1728 tipc_bearer_xmit_skb+0x228/0x3c0 net/tipc/bearer.c:574 tipc_disc_timeout+0x568/0x6b0 net/tipc/discover.c:338 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x525/0x7c0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:unix_wait_for_peer+0x1e8/0x2e0 net/unix/af_unix.c:-1 Code: f6 f8 49 81 c7 70 06 00 00 4c 89 ff e8 01 42 29 01 44 39 6c 24 1c 76 3b e8 e5 38 f6 f8 48 8b 7c 24 10 e8 5b fc 28 01 49 89 c7 31 e8 d1 38 f6 f8 eb 05 e8 ca 38 f6 f8 4c 8d 6c 24 40 49 81 c7 RSP: 0018:ffffc900033f7680 EFLAGS: 00000246 RAX: 7fffffffffffffff RBX: dffffc0000000000 RCX: ffffffff89a9a3d2 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888027375940 RBP: ffffc900033f7770 R08: dffffc0000000000 R09: ffffed1004e6eb29 R10: ffffed1004e6eb29 R11: 1ffff11004e6eb28 R12: ffff88807d1ad6c0 R13: 000000000000000a R14: 1ffff9200067eed4 R15: 7fffffffffffffff unix_dgram_sendmsg+0x106f/0x1890 net/unix/af_unix.c:1899 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490 __sys_sendmmsg+0x27c/0x4a0 net/socket.c:2576 __do_sys_sendmmsg net/socket.c:2605 [inline] __se_sys_sendmmsg net/socket.c:2602 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2602 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f59a8c43929 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:00007f59a6aab038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f59a8e6afa0 RCX: 00007f59a8c43929 RDX: 0000000000000651 RSI: 0000200000000000 RDI: 0000000000000005 RBP: 00007f59a8cc5b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f59a8e6afa0 R15: 00007ffd47ca3f58 ---------------- Code disassembly (best guess): 0: f6 f8 idiv %al 2: 49 81 c7 70 06 00 00 add $0x670,%r15 9: 4c 89 ff mov %r15,%rdi c: e8 01 42 29 01 call 0x1294212 11: 44 39 6c 24 1c cmp %r13d,0x1c(%rsp) 16: 76 3b jbe 0x53 18: e8 e5 38 f6 f8 call 0xf8f63902 1d: 48 8b 7c 24 10 mov 0x10(%rsp),%rdi 22: e8 5b fc 28 01 call 0x128fc82 27: 49 89 c7 mov %rax,%r15 * 2a: eb 31 jmp 0x5d <-- trapping instruction 2c: e8 d1 38 f6 f8 call 0xf8f63902 31: eb 05 jmp 0x38 33: e8 ca 38 f6 f8 call 0xf8f63902 38: 4c 8d 6c 24 40 lea 0x40(%rsp),%r13 3d: 49 rex.WB 3e: 81 .byte 0x81 3f: c7 .byte 0xc7