==================================================================
BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
Read of size 2 at addr ffff8880207ff02a by task kworker/u8:11/6558

CPU: 0 UID: 0 PID: 6558 Comm: kworker/u8:11 Not tainted 6.15.0-rc4-syzkaller-00152-g4397684a292a #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xb4/0x290 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789
 expire_timers kernel/time/timer.c:1840 [inline]
 __run_timers kernel/time/timer.c:2414 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426
 run_timer_base kernel/time/timer.c:2435 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__rcu_read_unlock+0x52/0xe0 kernel/rcu/tree_plugin.h:437
Code: 89 dc 49 c1 ec 03 43 0f b6 04 3c 84 c0 75 4f ff 0b 75 1d 4c 8d b7 48 04 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 75 66 <41> 83 3e 00 75 27 43 0f b6 04 3c 84 c0 75 41 8b 03 3d 00 00 00 40
RSP: 0018:ffffc9001ac3f910 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888065ea8444 RCX: 902ae1f6f5d13800
RDX: 0000000000000003 RSI: ffffffff8d935014 RDI: ffff888065ea8000
RBP: ffffc9001ac3fa70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8b1ed208 R12: 1ffff1100cbd5088
R13: dffffc0000000000 R14: ffff888065ea8448 R15: dffffc0000000000
 rcu_read_unlock include/linux/rcupdate.h:873 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:779 [inline]
 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline]
 batadv_iv_ogm_schedule+0x6d6/0xea0 net/batman-adv/bat_iv_ogm.c:876
 batadv_iv_send_outstanding_bat_ogm_packet+0x6c6/0x7e0 net/batman-adv/bat_iv_ogm.c:1720
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 13485:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4341 [inline]
 __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x4b3/0x1360 net/ipv6/route.c:3802
 ip6_route_add+0x28/0x160 net/ipv6/route.c:3896
 addrconf_add_mroute net/ipv6/addrconf.c:2551 [inline]
 addrconf_add_dev+0x24f/0x340 net/ipv6/addrconf.c:2569
 inet6_addr_add+0x1a1/0xc00 net/ipv6/addrconf.c:3031
 inet6_rtm_newaddr+0x93d/0xd20 net/ipv6/addrconf.c:5060
 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6955
 netlink_rcv_skb+0x219/0x490 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 15:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2398 [inline]
 slab_free mm/slub.c:4656 [inline]
 kfree+0x193/0x440 mm/slub.c:4855
 rcu_do_batch kernel/rcu/tree.c:2568 [inline]
 rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2824
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968
 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:548
 __call_rcu_common kernel/rcu/tree.c:3082 [inline]
 call_rcu+0x142/0x990 kernel/rcu/tree.c:3202
 call_rcu_hurry include/linux/rcupdate.h:115 [inline]
 fib6_info_release include/net/ip6_fib.h:343 [inline]
 ip6_route_info_create+0xab1/0x1360 net/ipv6/route.c:3882
 ip6_route_add+0x28/0x160 net/ipv6/route.c:3896
 addrconf_add_mroute net/ipv6/addrconf.c:2551 [inline]
 addrconf_add_dev+0x24f/0x340 net/ipv6/addrconf.c:2569
 inet6_addr_add+0x1a1/0xc00 net/ipv6/addrconf.c:3031
 inet6_rtm_newaddr+0x93d/0xd20 net/ipv6/addrconf.c:5060
 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6955
 netlink_rcv_skb+0x219/0x490 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880207ff000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff8880207ff000, ffff8880207ff200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x207fc
head: order:2 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 ffff88801a041c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a041c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea000081ff01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5826, tgid 5826 (syz-executor), ts 84371516889, free_ts 84358389061
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2468 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2632
 new_slab mm/slub.c:2686 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3872
 __slab_alloc mm/slub.c:3962 [inline]
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 __do_kmalloc_node mm/slub.c:4340 [inline]
 __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x4b3/0x1360 net/ipv6/route.c:3802
 ip6_route_add+0x28/0x160 net/ipv6/route.c:3896
 addrconf_prefix_route net/ipv6/addrconf.c:2487 [inline]
 addrconf_add_linklocal+0x45f/0x6c0 net/ipv6/addrconf.c:3315
 addrconf_addr_gen+0x490/0x580 net/ipv6/addrconf.c:3444
 addrconf_init_auto_addrs+0x7b6/0xb80 net/ipv6/addrconf.c:-1
 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3741
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline]
 call_netdevice_notifiers net/core/dev.c:2228 [inline]
 __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1
page last free pid 5189 tgid 5189 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0xb0e/0xcd0 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2730 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3199
 put_cpu_partial+0x17c/0x250 mm/slub.c:3274
 __slab_free+0x2f7/0x400 mm/slub.c:4526
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4161 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4262
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:658
 alloc_skb include/linux/skbuff.h:1340 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6639
 sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2954
 unix_dgram_sendmsg+0x5c2/0x17c0 net/unix/af_unix.c:2007
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94

Memory state around the buggy address:
 ffff8880207fef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880207fef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880207ff000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff8880207ff080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880207ff100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	89 dc                	mov    %ebx,%esp
   2:	49 c1 ec 03          	shr    $0x3,%r12
   6:	43 0f b6 04 3c       	movzbl (%r12,%r15,1),%eax
   b:	84 c0                	test   %al,%al
   d:	75 4f                	jne    0x5e
   f:	ff 0b                	decl   (%rbx)
  11:	75 1d                	jne    0x30
  13:	4c 8d b7 48 04 00 00 	lea    0x448(%rdi),%r14
  1a:	4c 89 f0             	mov    %r14,%rax
  1d:	48 c1 e8 03          	shr    $0x3,%rax
  21:	42 0f b6 04 38       	movzbl (%rax,%r15,1),%eax
  26:	84 c0                	test   %al,%al
  28:	75 66                	jne    0x90
* 2a:	41 83 3e 00          	cmpl   $0x0,(%r14) <-- trapping instruction
  2e:	75 27                	jne    0x57
  30:	43 0f b6 04 3c       	movzbl (%r12,%r15,1),%eax
  35:	84 c0                	test   %al,%al
  37:	75 41                	jne    0x7a
  39:	8b 03                	mov    (%rbx),%eax
  3b:	3d 00 00 00 40       	cmp    $0x40000000,%eax