==================================================================
BUG: KASAN: use-after-free in rose_timer_expiry+0x471/0x4b0 net/rose/rose_timer.c:183
Read of size 2 at addr ffff88805523342a by task syz.4.1216/10210

CPU: 0 UID: 0 PID: 10210 Comm: syz.4.1216 Not tainted 6.16.0-rc5-syzkaller-01458-gc3886ccaadf8 #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+0xd2/0x2b0 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+0x17e/0x5f0 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1798 [inline]
 __run_timers kernel/time/timer.c:2372 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 handle_softirqs+0x286/0x870 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:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:68 [inline]
RIP: 0010:atomic_long_read include/linux/atomic/atomic-instrumented.h:3188 [inline]
RIP: 0010:__mutex_owner kernel/locking/mutex.h:47 [inline]
RIP: 0010:mutex_spin_on_owner+0x27b/0x360 kernel/locking/mutex.c:351
Code: be 08 00 00 00 e8 b5 f6 85 00 42 80 7c 35 00 00 74 08 4c 89 e7 e8 35 f4 85 00 49 f7 04 24 01 00 00 00 0f 85 8c 00 00 00 f3 90 <4c> 89 e7 be 08 00 00 00 e8 88 f6 85 00 42 80 7c 35 00 00 0f 84 90
RSP: 0018:ffffc90005736e88 EFLAGS: 00000246
RAX: 1ffff11005659b40 RBX: ffffffff8f520630 RCX: ffffffff819dc408
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
RBP: 1ffffffff1ea40bc R08: ffffffff8f5205e7 R09: 1ffffffff1ea40bc
R10: dffffc0000000000 R11: fffffbfff1ea40bd R12: ffffffff8f5205e0
R13: ffffffff8f520630 R14: dffffc0000000000 R15: ffff88802e068000
 mutex_optimistic_spin kernel/locking/mutex.c:468 [inline]
 __mutex_lock_common kernel/locking/mutex.c:606 [inline]
 __mutex_lock+0x30c/0xe80 kernel/locking/mutex.c:747
 rtnl_lock net/core/rtnetlink.c:80 [inline]
 rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6946
 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x759/0x8e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcde9f8e929
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:00007fcdeade1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fcdea1b6080 RCX: 00007fcde9f8e929
RDX: 000000000000c0b0 RSI: 0000200000000280 RDI: 0000000000000005
RBP: 00007fcdea010ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fcdea1b6080 R15: 00007ffe8f1a1828
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55233
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9613, tgid 9608 (syz.2.1042), ts 240935895045, free_ts 254815274353
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2619
 new_slab mm/slub.c:2673 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859
 __slab_alloc mm/slub.c:3949 [inline]
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 genradix_alloc_node include/linux/generic-radix-tree.h:101 [inline]
 __genradix_ptr_alloc+0x352/0x4a0 lib/generic-radix-tree.c:69
 __genradix_prealloc+0x44/0x90 lib/generic-radix-tree.c:216
 sctp_stream_alloc_out net/sctp/stream.c:104 [inline]
 sctp_stream_init+0x14b/0x440 net/sctp/stream.c:149
 sctp_association_init net/sctp/associola.c:232 [inline]
 sctp_association_new+0x10dd/0x25f0 net/sctp/associola.c:296
 sctp_connect_new_asoc+0x2c5/0x690 net/sctp/socket.c:1092
 __sctp_connect+0x5ba/0xd50 net/sctp/socket.c:1198
 __sctp_setsockopt_connectx net/sctp/socket.c:1337 [inline]
 sctp_getsockopt_connectx3+0x2c4/0x440 net/sctp/socket.c:1422
 sctp_getsockopt+0x98a/0xb60 net/sctp/socket.c:8134
 do_sock_getsockopt+0x360/0x650 net/socket.c:2405
page last free pid 9984 tgid 9983 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3186
 put_cpu_partial+0x17c/0x250 mm/slub.c:3261
 __slab_free+0x2f7/0x400 mm/slub.c:4513
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 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:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 __kmalloc_cache_noprof+0x1be/0x3d0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271
 __netns_tracker_alloc include/net/net_namespace.h:357 [inline]
 netns_tracker_alloc include/net/net_namespace.h:366 [inline]
 get_net_track include/net/net_namespace.h:383 [inline]
 sk_alloc+0x1b1/0x370 net/core/sock.c:2301
 __netlink_create+0x65/0x260 net/netlink/af_netlink.c:628
 netlink_create+0x3ca/0x590 net/netlink/af_netlink.c:686
 __sock_create+0x4b0/0x9f0 net/socket.c:1589
 sock_create net/socket.c:1647 [inline]
 __sys_socket_create net/socket.c:1684 [inline]
 __sys_socket+0xd7/0x1b0 net/socket.c:1731
 __do_sys_socket net/socket.c:1745 [inline]
 __se_sys_socket net/socket.c:1743 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1743
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94

Memory state around the buggy address:
 ffff888055233300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888055233380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888055233400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                  ^
 ffff888055233480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888055233500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
----------------
Code disassembly (best guess):
   0:	be 08 00 00 00       	mov    $0x8,%esi
   5:	e8 b5 f6 85 00       	call   0x85f6bf
   a:	42 80 7c 35 00 00    	cmpb   $0x0,0x0(%rbp,%r14,1)
  10:	74 08                	je     0x1a
  12:	4c 89 e7             	mov    %r12,%rdi
  15:	e8 35 f4 85 00       	call   0x85f44f
  1a:	49 f7 04 24 01 00 00 	testq  $0x1,(%r12)
  21:	00
  22:	0f 85 8c 00 00 00    	jne    0xb4
  28:	f3 90                	pause
* 2a:	4c 89 e7             	mov    %r12,%rdi <-- trapping instruction
  2d:	be 08 00 00 00       	mov    $0x8,%esi
  32:	e8 88 f6 85 00       	call   0x85f6bf
  37:	42 80 7c 35 00 00    	cmpb   $0x0,0x0(%rbp,%r14,1)
  3d:	0f                   	.byte 0xf
  3e:	84                   	.byte 0x84
  3f:	90                   	nop