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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88803fdad42a by task syz.1.11377/6641

CPU: 0 UID: 0 PID: 6641 Comm: syz.1.11377 Not tainted 6.17.0-rc1-syzkaller-00207-g815957293639 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 rose_timer_expiry+0x471/0x4b0
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x175/0x360
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 eb e3 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900081a72b0 EFLAGS: 00000206
RAX: f1b0d77d70e79b00 RBX: 0000000000000000 RCX: f1b0d77d70e79b00
RDX: 0000000000000000 RSI: ffffffff8dba6149 RDI: ffffffff8be33400
RBP: ffffffff822e4087 R08: 0000000000000000 R09: ffffffff822e4087
R10: dffffc0000000000 R11: fffff9400016c229 R12: 0000000000000002
R13: ffffffff8e139ee0 R14: 0000000000000000 R15: 0000000000000246
 page_table_check_clear+0x1a4/0x700
 unmap_page_range+0x3445/0x4370
 unmap_vmas+0x399/0x580
 exit_mmap+0x248/0xb50
 __mmput+0x118/0x420
 exit_mm+0x1da/0x2c0
 do_exit+0x648/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3d60f8ebe9
Code: Unable to access opcode bytes at 0x7f3d60f8ebbf.
RSP: 002b:00007f3d61d110e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f3d611b6098 RCX: 00007f3d60f8ebe9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3d611b6098
RBP: 00007f3d611b6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3d611b6128 R14: 00007fffbfedde20 R15: 00007fffbfeddf08
 </TASK>

Allocated by task 6259:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 __ipv6_dev_mc_inc+0x44f/0xa50
 ipv6_add_dev+0xe54/0x1370
 addrconf_notify+0x794/0x1010
 notifier_call_chain+0x1b6/0x3e0
 register_netdevice+0x1608/0x1ae0
 tun_set_iff+0x844/0xf00
 __tun_chr_ioctl+0x788/0x1df0
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 856:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kmem_cache_free_bulk+0x2d1/0x520
 kvfree_rcu_bulk+0xe5/0x1f0
 kfree_rcu_monitor+0x211/0x2a0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60
 kasan_record_aux_stack+0xbd/0xd0
 kvfree_call_rcu+0xbb/0x410
 ipv6_mc_destroy_dev+0x3c5/0x5a0
 addrconf_ifdown+0x139e/0x1880
 addrconf_notify+0x1bc/0x1010
 notifier_call_chain+0x1b6/0x3e0
 netif_set_mtu_ext+0x594/0x7d0
 netif_set_mtu+0xa4/0x150
 dev_set_mtu+0x126/0x260
 dev_ioctl+0x7b4/0x1150
 sock_do_ioctl+0x22c/0x300
 sock_ioctl+0x576/0x790
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88803fdad400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff88803fdad400, ffff88803fdad600)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88803fdad400 pfn:0x3fdac
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 ffff88801a441c80 ffffea0000c18010 ffffea0000a7d110
raw: ffff88803fdad400 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea0000c18010 ffffea0000a7d110
head: ffff88803fdad400 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000ff6b01 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 23917, tgid 23916 (syz.2.6167), ts 354386921695, free_ts 349942651225
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x8a/0x370
 ___slab_alloc+0xbeb/0x1410
 __kmalloc_cache_noprof+0x296/0x3d0
 __genradix_ptr_alloc+0x352/0x4a0
 __genradix_prealloc+0x44/0x90
 sctp_stream_init+0x14b/0x440
 sctp_association_new+0x10dd/0x25f0
 sctp_connect_new_asoc+0x2c5/0x690
 sctp_sendmsg+0x155c/0x2810
 __sock_sendmsg+0x19c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
page last free pid 23651 tgid 23650 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 vfree+0x25a/0x400
 __vmalloc_node_range_noprof+0x100d/0x12f0
 bpf_map_area_alloc+0x12d/0x180
 bloom_map_alloc+0x22f/0x470
 map_create+0xaa3/0x14d0
 __sys_bpf+0x60f/0x870
 __x64_sys_bpf+0x7c/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88803fdad300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88803fdad380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803fdad400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88803fdad480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803fdad500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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