ip6_tunnel: ip6gretap0 xmit: Local address not yet configured!
==================================================================
BUG: KASAN: slab-use-after-free in ax25_heartbeat_expiry+0x115/0x140 net/ax25/ax25_timer.c:127
Read of size 4 at addr ffff88807c420260 by task syz-executor/5822

CPU: 0 UID: 0 PID: 5822 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xba/0x230 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 ax25_heartbeat_expiry+0x115/0x140 net/ax25/ax25_timer.c:127
 call_timer_fn+0x192/0x5a0 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
 run_timer_base kernel/time/timer.c:2394 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:seqcount_lockdep_reader_access+0x9d/0xc0 include/linux/seqlock.h:76
Code: 80 ff 48 83 c4 08 48 89 df 4c 89 f6 e8 6c 87 80 ff e8 c7 0f ac ff 9c 58 a9 00 02 00 00 75 15 41 f7 c7 00 02 00 00 74 01 fb 5b <41> 5e 41 5f c3 cc cc cc cc cc e8 24 3e 7e 09 41 f7 c7 00 02 00 00
RSP: 0018:ffffc9000420efc0 EFLAGS: 00000206
RAX: 0000000000000002 RBX: ffff88813fffbb80 RCX: 0000000000000046
RDX: 0000000000000006 RSI: ffffffff8dee2508 RDI: ffffffff8c276500
RBP: ffffea0000472780 R08: ffffffff90109077 R09: 1ffffffff202120e
R10: dffffc0000000000 R11: fffffbfff202120f R12: 1ffff11027fff78a
R13: ffff88813fffbc20 R14: ffffffff821ffd3b R15: 0000000000000a06
 read_seqbegin include/linux/seqlock.h:838 [inline]
 zone_span_seqbegin include/linux/memory_hotplug.h:87 [inline]
 page_outside_zone_boundaries mm/page_alloc.c:613 [inline]
 bad_range+0x8b/0x2c0 mm/page_alloc.c:632
 rmqueue mm/page_alloc.c:3423 [inline]
 get_page_from_freelist+0x24bb/0x2580 mm/page_alloc.c:3947
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5245
 __alloc_pages_noprof mm/page_alloc.c:5279 [inline]
 alloc_pages_bulk_noprof+0x558/0x700 mm/page_alloc.c:5199
 ___alloc_pages_bulk mm/kasan/shadow.c:345 [inline]
 __kasan_populate_vmalloc_do mm/kasan/shadow.c:370 [inline]
 __kasan_populate_vmalloc+0xc1/0x1d0 mm/kasan/shadow.c:424
 kasan_populate_vmalloc include/linux/kasan.h:580 [inline]
 alloc_vmap_area+0xdbc/0x14a0 mm/vmalloc.c:2124
 __get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3219
 __vmalloc_node_range_noprof+0x372/0x1730 mm/vmalloc.c:4011
 __vmalloc_node_noprof mm/vmalloc.c:4111 [inline]
 vzalloc_noprof+0xb2/0xe0 mm/vmalloc.c:4189
 alloc_counters+0x64/0x5d0 net/ipv4/netfilter/ip_tables.c:799
 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:821 [inline]
 get_entries net/ipv4/netfilter/ip_tables.c:1022 [inline]
 do_ipt_get_ctl+0xada/0x1240 net/ipv4/netfilter/ip_tables.c:1668
 nf_getsockopt+0x26e/0x290 net/netfilter/nf_sockopt.c:116
 ip_getsockopt+0x19e/0x230 net/ipv4/ip_sockglue.c:1777
 do_sock_getsockopt+0x2d3/0x3f0 net/socket.c:2383
 __sys_getsockopt net/socket.c:2412 [inline]
 __do_sys_getsockopt net/socket.c:2419 [inline]
 __se_sys_getsockopt net/socket.c:2416 [inline]
 __x64_sys_getsockopt+0x1a4/0x240 net/socket.c:2416
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd97059de2a
Code: 48 83 ec 10 89 d2 48 63 ff 45 31 c9 6a 2a 45 31 c0 31 c9 e8 18 9a fb ff 48 83 c4 18 c3 0f 1f 00 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 e8 ff ff ff f7
RSP: 002b:00007ffc665647a8 EFLAGS: 00000216 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007ffc66564830 RCX: 00007fd97059de2a
RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007ffc665647cc R09: 0000000000000000
R10: 00007ffc66564830 R11: 0000000000000216 R12: 00007fd9707eaac0
R13: 00007ffc665647cc R14: 0000000000000000 R15: 00007fd9707eb180
 </TASK>

Allocated by task 6292:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5297
 kmalloc_noprof include/linux/slab.h:962 [inline]
 kzalloc_noprof include/linux/slab.h:1204 [inline]
 ax25_dev_device_up+0x54/0x5f0 net/ax25/ax25_dev.c:57
 ax25_device_event+0x127/0x8a0 net/ax25/af_ax25.c:143
 notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2280 [inline]
 call_netdevice_notifiers net/core/dev.c:2294 [inline]
 __dev_notify_flags+0x1a9/0x310 net/core/dev.c:9785
 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9814
 dev_change_flags+0x130/0x260 net/core/dev_api.c:68
 dev_ioctl+0x7b4/0x1150 net/core/dev_ioctl.c:814
 sock_do_ioctl+0x23e/0x320 net/socket.c:1268
 sock_ioctl+0x5c6/0x7f0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 8714:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2670 [inline]
 __rcu_free_sheaf_prepare+0x129/0x290 mm/slub.c:2900
 rcu_free_sheaf+0x31/0x200 mm/slub.c:5728
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869
 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

The buggy address belongs to the object at ffff88807c420200
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 96 bytes inside of
 freed 256-byte region [ffff88807c420200, ffff88807c420300)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c420
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813fe9ab40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813fe9ab40 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffea0001f10801 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5820, tgid 5820 (syz-executor), ts 91895029504, free_ts 91891164871
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884
 prep_new_page mm/page_alloc.c:1892 [inline]
 get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3950
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5245
 alloc_slab_page mm/slub.c:3238 [inline]
 allocate_slab+0x77/0x660 mm/slub.c:3411
 new_slab mm/slub.c:3469 [inline]
 refill_objects+0x331/0x3c0 mm/slub.c:7091
 refill_sheaf mm/slub.c:2787 [inline]
 __pcs_replace_empty_main+0x2b9/0x620 mm/slub.c:4536
 alloc_from_pcs mm/slub.c:4639 [inline]
 slab_alloc_node mm/slub.c:4773 [inline]
 __do_kmalloc_node mm/slub.c:5176 [inline]
 __kmalloc_noprof+0x474/0x760 mm/slub.c:5189
 kmalloc_noprof include/linux/slab.h:966 [inline]
 kzalloc_noprof include/linux/slab.h:1204 [inline]
 fib_create_info+0x171d/0x31f0 net/ipv4/fib_semantics.c:1402
 fib_table_insert+0xc8/0x1b50 net/ipv4/fib_trie.c:1212
 fib_magic+0x434/0x510 net/ipv4/fib_frontend.c:1134
 fib_add_ifaddr+0x144/0x5f0 net/ipv4/fib_frontend.c:1156
 fib_inetaddr_event+0x12e/0x190 net/ipv4/fib_frontend.c:1470
 notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380
 __inet_insert_ifa+0x9e9/0xbc0 net/ipv4/devinet.c:566
 inet_rtm_newaddr+0x10d8/0x1ad0 net/ipv4/devinet.c:1001
page last free pid 5926 tgid 5926 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0xbf8/0xd70 mm/page_alloc.c:2973
 mm_free_pgd kernel/fork.c:585 [inline]
 __mmdrop+0xb5/0x750 kernel/fork.c:727
 exit_mm+0x168/0x220 kernel/exit.c:581
 do_exit+0x62e/0x2310 kernel/exit.c:959
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112
 __do_sys_exit_group kernel/exit.c:1123 [inline]
 __se_sys_exit_group kernel/exit.c:1121 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121
 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88807c420100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807c420180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807c420200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff88807c420280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807c420300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
   0:	80 ff 48             	cmp    $0x48,%bh
   3:	83 c4 08             	add    $0x8,%esp
   6:	48 89 df             	mov    %rbx,%rdi
   9:	4c 89 f6             	mov    %r14,%rsi
   c:	e8 6c 87 80 ff       	call   0xff80877d
  11:	e8 c7 0f ac ff       	call   0xffac0fdd
  16:	9c                   	pushf
  17:	58                   	pop    %rax
  18:	a9 00 02 00 00       	test   $0x200,%eax
  1d:	75 15                	jne    0x34
  1f:	41 f7 c7 00 02 00 00 	test   $0x200,%r15d
  26:	74 01                	je     0x29
  28:	fb                   	sti
  29:	5b                   	pop    %rbx
* 2a:	41 5e                	pop    %r14 <-- trapping instruction
  2c:	41 5f                	pop    %r15
  2e:	c3                   	ret
  2f:	cc                   	int3
  30:	cc                   	int3
  31:	cc                   	int3
  32:	cc                   	int3
  33:	cc                   	int3
  34:	e8 24 3e 7e 09       	call   0x97e3e5d
  39:	41 f7 c7 00 02 00 00 	test   $0x200,%r15d