==================================================================
BUG: KASAN: slab-use-after-free in rose_get_neigh+0x1b6/0x6f0 net/rose/rose_route.c:692
Read of size 1 at addr ffff888024a88030 by task syz.2.1410/10542

CPU: 1 UID: 0 PID: 10542 Comm: syz.2.1410 Not tainted 6.14.0-rc7-syzkaller-01413-gd9917c7d533c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 rose_get_neigh+0x1b6/0x6f0 net/rose/rose_route.c:692
 rose_connect+0x45a/0x1170 net/rose/af_rose.c:816
 __sys_connect_file net/socket.c:2036 [inline]
 __sys_connect+0x288/0x2d0 net/socket.c:2055
 __do_sys_connect net/socket.c:2061 [inline]
 __se_sys_connect net/socket.c:2058 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2058
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffb2f98d169
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:00007ffb2d7d5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007ffb2fba6080 RCX: 00007ffb2f98d169
RDX: 0000000000000040 RSI: 0000200000000040 RDI: 0000000000000008
RBP: 00007ffb2fa0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ffb2fba6080 R15: 00007ffdfc170078
 </TASK>

Allocated by task 8464:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4325
 kmalloc_noprof include/linux/slab.h:901 [inline]
 batadv_forw_packet_alloc+0x19c/0x3b0 net/batman-adv/send.c:519
 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:571 [inline]
 batadv_iv_ogm_queue_add+0x7f6/0xd20 net/batman-adv/bat_iv_ogm.c:678
 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:857 [inline]
 batadv_iv_ogm_schedule+0xc5c/0x10a0 net/batman-adv/bat_iv_ogm.c:876
 batadv_iv_send_outstanding_bat_ogm_packet+0x68f/0x7a0 net/batman-adv/bat_iv_ogm.c:1720
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 3450:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4609 [inline]
 kfree+0x196/0x430 mm/slub.c:4757
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xaa/0xc0 mm/kasan/generic.c:548
 insert_work+0x3e/0x330 kernel/workqueue.c:2183
 __queue_work+0xc62/0x1090 kernel/workqueue.c:2345
 call_timer_fn+0x187/0x650 kernel/time/timer.c:1789
 expire_timers kernel/time/timer.c:1835 [inline]
 __run_timers kernel/time/timer.c:2414 [inline]
 __run_timer_base+0x695/0x8e0 kernel/time/timer.c:2426
 run_timer_base kernel/time/timer.c:2435 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2445
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

The buggy address belongs to the object at ffff888024a88000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 48 bytes inside of
 freed 512-byte region [ffff888024a88000, ffff888024a88200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888024a88400 pfn:0x24a88
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88801b041c80 ffffea0001f8f510 ffffea0001efc210
raw: ffff888024a88400 000000000010000e 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801b041c80 ffffea0001f8f510 ffffea0001efc210
head: ffff888024a88400 000000000010000e 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea000092a201 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 53, tgid 53 (kworker/u8:3), ts 80189702672, free_ts 80091869513
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4740
 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:2423 [inline]
 allocate_slab+0x8f/0x3a0 mm/slub.c:2587
 new_slab mm/slub.c:2640 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826
 __slab_alloc+0x58/0xa0 mm/slub.c:3916
 __slab_alloc_node mm/slub.c:3991 [inline]
 slab_alloc_node mm/slub.c:4152 [inline]
 __do_kmalloc_node mm/slub.c:4293 [inline]
 __kmalloc_noprof+0x2e6/0x4c0 mm/slub.c:4306
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 fib6_info_alloc+0x2e/0xf0 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x445/0x12c0 net/ipv6/route.c:3767
 ip6_route_add+0x28/0x160 net/ipv6/route.c:3861
 addrconf_add_mroute net/ipv6/addrconf.c:2549 [inline]
 addrconf_add_dev+0x35b/0x540 net/ipv6/addrconf.c:2567
 addrconf_dev_config net/ipv6/addrconf.c:3475 [inline]
 addrconf_init_auto_addrs+0x85f/0xeb0 net/ipv6/addrconf.c:3563
 addrconf_notify+0xaff/0x1020 net/ipv6/addrconf.c:3736
 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
 netdev_state_change+0x11f/0x1a0 net/core/dev.c:1522
page last free pid 5846 tgid 5846 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660
 discard_slab mm/slub.c:2684 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3153
 put_cpu_partial+0x17c/0x250 mm/slub.c:3228
 __slab_free+0x290/0x380 mm/slub.c:4479
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:385
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4294 [inline]
 __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4306
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 fib_create_info+0x1109/0x2cb0 net/ipv4/fib_semantics.c:1407
 fib_table_insert+0x147/0x1d10 net/ipv4/fib_trie.c:1212
 fib_magic+0x3d8/0x620 net/ipv4/fib_frontend.c:1133
 fib_add_ifaddr+0x40c/0x5e0 net/ipv4/fib_frontend.c:1177
 fib_netdev_event+0x375/0x490 net/ipv4/fib_frontend.c:1515
 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85
 __dev_notify_flags+0x207/0x400
 netif_change_flags+0xf0/0x1a0 net/core/dev.c:9406

Memory state around the buggy address:
 ffff888024a87f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888024a87f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888024a88000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888024a88080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888024a88100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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