==================================================================
BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:989 [inline]
BUG: KASAN: slab-use-after-free in detach_timer+0xc8/0x300 kernel/time/timer.c:891
Read of size 8 at addr ffff88805e1a04d0 by task ktimers/1/29

CPU: 1 UID: 0 PID: 29 Comm: ktimers/1 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 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
 __hlist_del include/linux/list.h:989 [inline]
 detach_timer+0xc8/0x300 kernel/time/timer.c:891
 expire_timers kernel/time/timer.c:1782 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x624/0x9f0 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+0x1de/0x6f0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0x69/0x100 kernel/softirq.c:1138
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 19327:
 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+0x3a6/0x690 mm/slub.c:5339
 kmalloc_noprof include/linux/slab.h:962 [inline]
 rose_add_node+0x26f/0xf50 net/rose/rose_route.c:85
 rose_rt_ioctl+0xdc1/0x1350 net/rose/rose_route.c:748
 rose_ioctl+0x3fb/0x8f0 net/rose/af_rose.c:1382
 sock_do_ioctl+0x101/0x320 net/socket.c:1254
 sock_ioctl+0x5c9/0x7f0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xff/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 29:
 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:2687 [inline]
 slab_free mm/slub.c:6124 [inline]
 kfree+0x1c1/0x6c0 mm/slub.c:6442
 rose_neigh_put include/net/rose.h:166 [inline]
 rose_timer_expiry+0x4cb/0x600 net/rose/rose_timer.c:183
 call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x6a3/0x9f0 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+0x1de/0x6f0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0x69/0x100 kernel/softirq.c:1138
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88805e1a0400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 208 bytes inside of
 freed 512-byte region [ffff88805e1a0400, ffff88805e1a0600)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805e1a3c00 pfn:0x5e1a0
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000240(workingset|head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000240 ffff88813fe1cc80 ffffea0000eb6010 ffffea000189d510
raw: ffff88805e1a3c00 0000000000100007 00000000f5000000 0000000000000000
head: 0080000000000240 ffff88813fe1cc80 ffffea0000eb6010 ffffea000189d510
head: ffff88805e1a3c00 0000000000100007 00000000f5000000 0000000000000000
head: 0080000000000002 ffffea0001786801 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1421, tgid 1421 (kworker/u8:11), ts 82076958517, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
 alloc_slab_page mm/slub.c:3255 [inline]
 allocate_slab+0x77/0x660 mm/slub.c:3444
 new_slab mm/slub.c:3502 [inline]
 refill_objects+0x334/0x3c0 mm/slub.c:7134
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x328/0x5f0 mm/slub.c:4578
 alloc_from_pcs mm/slub.c:4681 [inline]
 slab_alloc_node mm/slub.c:4815 [inline]
 __do_kmalloc_node mm/slub.c:5218 [inline]
 __kmalloc_noprof+0x530/0x7b0 mm/slub.c:5231
 kmalloc_noprof include/linux/slab.h:966 [inline]
 kzalloc_noprof include/linux/slab.h:1200 [inline]
 fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x142/0x860 net/ipv6/route.c:3819
 ip6_route_add+0x49/0x1d0 net/ipv6/route.c:3948
 addrconf_add_mroute+0x2d1/0x370 net/ipv6/addrconf.c:2551
 addrconf_add_dev net/ipv6/addrconf.c:2569 [inline]
 addrconf_dev_config net/ipv6/addrconf.c:3483 [inline]
 addrconf_init_auto_addrs+0x4d7/0xa50 net/ipv6/addrconf.c:3571
 addrconf_notify+0xb1e/0x1050 net/ipv6/addrconf.c:3744
 notifier_call_chain+0x1be/0x400 kernel/notifier.c:85
 netif_state_change+0x27d/0x3a0 net/core/dev.c:1603
 __linkwatch_run_queue+0x575/0x850 net/core/link_watch.c:240
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88805e1a0380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805e1a0400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805e1a0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88805e1a0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805e1a0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================