==================================================================
BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
Read of size 2 at addr ffff888037f3802a by task syz.8.3792/20074

CPU: 1 UID: 0 PID: 20074 Comm: syz.8.3792 Not tainted 6.15.0-rc5-syzkaller-01070-g9f607dc39b66 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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_preempt_read_enter kernel/rcu/tree_plugin.h:391 [inline]
RIP: 0010:__rcu_read_lock+0x1c/0x60 kernel/rcu/tree_plugin.h:414
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 53 65 48 8b 1c 25 08 00 76 92 48 81 c3 44 04 00 00 48 89 d8 48 c1 e8 03 <48> b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 18 ff 03 8b 03
RSP: 0018:ffffc9000369f528 EFLAGS: 00000a07
RAX: 1ffff1100a3a1088 RBX: ffff888051d08444 RCX: ffff888051d08000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8880660880f0
RBP: 0000000000000000 R08: ffff88801aef70e7 R09: 1ffff110035dee1c
R10: dffffc0000000000 R11: ffffed10035dee1d R12: ffff88801aef70d8
R13: dffffc0000000000 R14: ffff8880660880f0 R15: ffff88801aef7170
 rcu_read_lock include/linux/rcupdate.h:839 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 kernfs_root+0x15/0x230 fs/kernfs/kernfs-internal.h:73
 kernfs_next_descendant_post fs/kernfs/dir.c:1371 [inline]
 kernfs_activate fs/kernfs/dir.c:1426 [inline]
 kernfs_add_one+0x2f5/0x520 fs/kernfs/dir.c:834
 __kernfs_create_file+0x22b/0x2e0 fs/kernfs/file.c:1067
 sysfs_add_file_mode_ns+0x238/0x300 fs/sysfs/file.c:319
 create_files fs/sysfs/group.c:76 [inline]
 internal_create_group+0x66d/0x1110 fs/sysfs/group.c:183
 internal_create_groups fs/sysfs/group.c:223 [inline]
 sysfs_create_groups+0x59/0x120 fs/sysfs/group.c:249
 setup_port drivers/infiniband/core/sysfs.c:1247 [inline]
 ib_setup_port_attrs+0xd96/0x2070 drivers/infiniband/core/sysfs.c:1433
 add_one_compat_dev+0x3d6/0x5c0 drivers/infiniband/core/device.c:968
 rdma_dev_init_net+0x1dd/0x270 drivers/infiniband/core/device.c:1184
 ops_init+0x359/0x5c0 net/core/net_namespace.c:138
 setup_net+0x219/0x4b0 net/core/net_namespace.c:442
 copy_net_ns+0x32e/0x590 net/core/net_namespace.c:574
 create_new_namespaces+0x3d3/0x700 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:228
 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3375
 __do_sys_unshare kernel/fork.c:3446 [inline]
 __se_sys_unshare kernel/fork.c:3444 [inline]
 __x64_sys_unshare+0x38/0x50 kernel/fork.c:3444
 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
RIP: 0033:0x7fbb4618e969
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:00007fbb46f0e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fbb463b5fa0 RCX: 00007fbb4618e969
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000
RBP: 00007fbb46210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbb463b5fa0 R15: 00007ffe7312aab8
 </TASK>

Allocated by task 1150:
 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]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 mld_add_delrec net/ipv6/mcast.c:746 [inline]
 igmp6_leave_group net/ipv6/mcast.c:2676 [inline]
 igmp6_group_dropped+0x3ac/0xf10 net/ipv6/mcast.c:726
 __ipv6_dev_mc_dec+0x2d2/0x390 net/ipv6/mcast.c:1018
 addrconf_leave_solict net/ipv6/addrconf.c:2254 [inline]
 __ipv6_ifa_notify+0x43d/0xac0 net/ipv6/addrconf.c:6302
 addrconf_ifdown+0xe69/0x1880 net/ipv6/addrconf.c:3981
 addrconf_notify+0x1bc/0x1010 net/ipv6/addrconf.c:-1
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2266 [inline]
 call_netdevice_notifiers net/core/dev.c:2280 [inline]
 dev_close_many+0x29c/0x410 net/core/dev.c:1783
 unregister_netdevice_many_notify+0x834/0x2320 net/core/dev.c:12024
 unregister_netdevice_many net/core/dev.c:12117 [inline]
 default_device_exit_batch+0x819/0x890 net/core/dev.c:12621
 ops_exit_list net/core/net_namespace.c:206 [inline]
 ops_undo_list+0x522/0x990 net/core/net_namespace.c:253
 cleanup_net+0x4c5/0x8a0 net/core/net_namespace.c:686
 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

Freed by task 18208:
 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:2380 [inline]
 slab_free_freelist_hook mm/slub.c:2409 [inline]
 slab_free_bulk mm/slub.c:4666 [inline]
 kmem_cache_free_bulk+0x2d1/0x520 mm/slub.c:5243
 kfree_bulk include/linux/slab.h:794 [inline]
 kvfree_rcu_bulk+0xe5/0x1e0 mm/slab_common.c:1516
 kvfree_rcu_drain_ready mm/slab_common.c:1699 [inline]
 kfree_rcu_monitor+0x211/0x2a0 mm/slab_common.c:1772
 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

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
 kvfree_call_rcu+0xbb/0x410 mm/slab_common.c:1962
 mld_clear_delrec+0x193/0x5d0 net/ipv6/mcast.c:828
 ipv6_mc_destroy_dev+0x45/0x5a0 net/ipv6/mcast.c:2842
 addrconf_ifdown+0x139e/0x1880 net/ipv6/addrconf.c:4000
 addrconf_notify+0x1bc/0x1010 net/ipv6/addrconf.c:-1
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2266 [inline]
 call_netdevice_notifiers net/core/dev.c:2280 [inline]
 unregister_netdevice_many_notify+0x15d8/0x2320 net/core/dev.c:12054
 unregister_netdevice_many net/core/dev.c:12117 [inline]
 default_device_exit_batch+0x819/0x890 net/core/dev.c:12621
 ops_exit_list net/core/net_namespace.c:206 [inline]
 ops_undo_list+0x522/0x990 net/core/net_namespace.c:253
 cleanup_net+0x4c5/0x8a0 net/core/net_namespace.c:686
 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

The buggy address belongs to the object at ffff888037f38000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff888037f38000, ffff888037f38200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x37f38
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 ffffea0000dfce01 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 36, tgid 36 (kworker/u8:2), ts 239361417286, free_ts 236582208647
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1714
 prep_new_page mm/page_alloc.c:1722 [inline]
 get_page_from_freelist+0x21e0/0x22c0 mm/page_alloc.c:3684
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4966
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2618
 new_slab mm/slub.c:2672 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858
 __slab_alloc mm/slub.c:3948 [inline]
 __slab_alloc_node mm/slub.c:4023 [inline]
 slab_alloc_node mm/slub.c:4184 [inline]
 __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 mca_alloc net/ipv6/mcast.c:884 [inline]
 __ipv6_dev_mc_inc+0x420/0xaf0 net/ipv6/mcast.c:975
 addrconf_join_solict net/ipv6/addrconf.c:2242 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:4103 [inline]
 addrconf_dad_work+0x3d0/0x14b0 net/ipv6/addrconf.c:4231
 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
page last free pid 10382 tgid 10382 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1258 [inline]
 __free_frozen_pages+0xb14/0xce0 mm/page_alloc.c:2721
 __folio_put+0x21b/0x2c0 mm/swap.c:112
 put_netmem net/core/skbuff.c:7347 [inline]
 skb_page_unref include/linux/skbuff_ref.h:43 [inline]
 __skb_frag_unref include/linux/skbuff_ref.h:56 [inline]
 skb_release_data+0x4df/0x8b0 net/core/skbuff.c:1080
 skb_release_all net/core/skbuff.c:1151 [inline]
 kfree_skb_add_bulk net/core/skbuff.c:1224 [inline]
 kfree_skb_list_reason+0x25d/0x460 net/core/skbuff.c:1246
 skb_release_data+0x5e2/0x8b0 net/core/skbuff.c:1084
 skb_release_all net/core/skbuff.c:1151 [inline]
 __kfree_skb net/core/skbuff.c:1165 [inline]
 sk_skb_reason_drop+0x127/0x170 net/core/skbuff.c:1203
 kfree_skb_reason include/linux/skbuff.h:1276 [inline]
 kfree_skb include/linux/skbuff.h:1285 [inline]
 kcm_release+0x149/0x5c0 net/kcm/kcmsock.c:1683
 __sock_release net/socket.c:647 [inline]
 sock_close+0xc0/0x240 net/socket.c:1391
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888037f37f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888037f37f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888037f38000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888037f38080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888037f38100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	90                   	nop
   2:	90                   	nop
   3:	90                   	nop
   4:	90                   	nop
   5:	90                   	nop
   6:	90                   	nop
   7:	90                   	nop
   8:	90                   	nop
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	f3 0f 1e fa          	endbr64
  12:	53                   	push   %rbx
  13:	65 48 8b 1c 25 08 00 	mov    %gs:0xffffffff92760008,%rbx
  1a:	76 92
  1c:	48 81 c3 44 04 00 00 	add    $0x444,%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx <-- trapping instruction
  31:	fc ff df
  34:	0f b6 04 08          	movzbl (%rax,%rcx,1),%eax
  38:	84 c0                	test   %al,%al
  3a:	75 18                	jne    0x54
  3c:	ff 03                	incl   (%rbx)
  3e:	8b 03                	mov    (%rbx),%eax