------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 0 PID: 9057 at lib/refcount.c:25 refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25 Modules linked in: CPU: 0 PID: 9057 Comm: syz-executor 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:ffffc90000007848 EFLAGS: 00010246 RAX: 3a3aa903d22cff00 RBX: 0000000000000002 RCX: ffff88805ae35940 RDX: 0000000000000100 RSI: 0000000000000100 RDI: 0000000000000000 RBP: ffffc900000079b0 R08: dffffc0000000000 R09: fffff52000000e6d R10: fffff52000000e6d R11: 1ffff92000000e6c R12: ffff88801a5a8000 R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000000 FS: 000055555efbd500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000404030 CR3: 000000007c93b000 CR4: 00000000003506f0 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_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:stack_trace_consume_entry+0x12e/0x270 kernel/stacktrace.c:95 Code: e8 4c 89 e2 48 89 de 49 89 37 41 8b 18 41 0f b6 44 15 00 84 c0 0f 85 2f 01 00 00 41 3b 1e 0f 92 c0 48 83 c4 18 5b 41 5c 41 5d <41> 5e 41 5f 5d c3 44 89 c1 80 e1 07 80 c1 03 38 c1 0f 8c eb fe ff RSP: 0018:ffffc900039cf1a8 EFLAGS: 00000296 RAX: 0000000000000001 RBX: ffffc900039cf280 RCX: 0000000080000001 RDX: dffffc0000000000 RSI: ffffffff81af3492 RDI: ffffc900039cf280 RBP: 1ffff92000739e52 R08: ffffc900039cf290 R09: 000000000000000e R10: fffff52000739e45 R11: 1ffff92000739e43 R12: ffff88805ae35940 R13: 1ffff92000739e64 R14: ffffc900039cf288 R15: ffffc900039cf3b0 arch_stack_walk+0x100/0x140 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122 save_stack+0xf3/0x1e0 mm/page_owner.c:119 __set_page_owner+0x41/0x2d0 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5474 __get_free_pages+0x8/0x30 mm/page_alloc.c:5511 kasan_populate_vmalloc_pte+0x21/0xc0 mm/kasan/shadow.c:266 apply_to_pte_range mm/memory.c:2573 [inline] apply_to_pmd_range mm/memory.c:2617 [inline] apply_to_pud_range mm/memory.c:2653 [inline] apply_to_p4d_range mm/memory.c:2689 [inline] __apply_to_page_range+0x95c/0xc80 mm/memory.c:2725 alloc_vmap_area+0x19f7/0x1b20 mm/vmalloc.c:1565 __get_vm_area_node+0x14f/0x2d0 mm/vmalloc.c:2423 __vmalloc_node_range+0xef/0x8b0 mm/vmalloc.c:3020 vmalloc_user+0x70/0x80 mm/vmalloc.c:3166 kcov_mmap+0x27/0x120 kernel/kcov.c:474 call_mmap include/linux/fs.h:2177 [inline] mmap_file+0x5d/0xb0 mm/util.c:1092 __mmap_region mm/mmap.c:1784 [inline] mmap_region+0xd0d/0x15e0 mm/mmap.c:2921 do_mmap+0x77a/0xdf0 mm/mmap.c:1574 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:551 ksys_mmap_pgoff+0x542/0x780 mm/mmap.c:1623 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: 0033:0x7f5777301963 Code: f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 41 89 ca 41 f7 c1 ff 0f 00 00 75 14 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 25 c3 0f 1f 40 00 48 c7 c0 a8 ff ff ff 64 c7 RSP: 002b:00007ffdf79c1c28 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f5777529118 RCX: 00007f5777301963 RDX: 0000000000000003 RSI: 0000000000400000 RDI: 00007f5776570000 RBP: 00007f5777529118 R08: 00000000000000d9 R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: e8 4c 89 e2 48 call 0x48e28951 5: 89 de mov %ebx,%esi 7: 49 89 37 mov %rsi,(%r15) a: 41 8b 18 mov (%r8),%ebx d: 41 0f b6 44 15 00 movzbl 0x0(%r13,%rdx,1),%eax 13: 84 c0 test %al,%al 15: 0f 85 2f 01 00 00 jne 0x14a 1b: 41 3b 1e cmp (%r14),%ebx 1e: 0f 92 c0 setb %al 21: 48 83 c4 18 add $0x18,%rsp 25: 5b pop %rbx 26: 41 5c pop %r12 28: 41 5d pop %r13 * 2a: 41 5e pop %r14 <-- trapping instruction 2c: 41 5f pop %r15 2e: 5d pop %rbp 2f: c3 ret 30: 44 89 c1 mov %r8d,%ecx 33: 80 e1 07 and $0x7,%cl 36: 80 c1 03 add $0x3,%cl 39: 38 c1 cmp %al,%cl 3b: 0f .byte 0xf 3c: 8c eb mov %gs,%ebx 3e: fe (bad) 3f: ff .byte 0xff