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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff888026bebc2a by task syz.3.9000/31295

CPU: 0 UID: 0 PID: 31295 Comm: syz.3.9000 Not tainted 6.16.0-syzkaller-12063-g37816488247d-dirty #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:finish_task_switch+0x26b/0x950
Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 cf 37 ea 09 e8 5a 3f 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90003357938 EFLAGS: 00000282
RAX: 1555ef0147b46500 RBX: 0000000000000000 RCX: 1555ef0147b46500
RDX: 0000000000000000 RSI: ffffffff8d9b494b RDI: ffffffff8be32680
RBP: ffffc90003357990 R08: ffffffff8fa34737 R09: 1ffffffff1f468e6
R10: dffffc0000000000 R11: fffffbfff1f468e7 R12: ffff8881207a0000
R13: dffffc0000000000 R14: ffff888121fc0000 R15: ffff88804b03ab58
 __schedule+0x17a0/0x4cc0
 schedule+0x165/0x360
 do_nanosleep+0x1c7/0x600
 hrtimer_nanosleep+0x169/0x360
 __se_sys_clock_nanosleep+0x2f1/0x380
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f97c73c14a5
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8
RSP: 002b:00007fff60bc5440 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 00007f97c75b5fa0 RCX: 00007f97c73c14a5
RDX: 00007fff60bc5480 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f97c75b7da0 R08: 0000000000000000 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000009e9cf
R13: 00007f97c75b6090 R14: ffffffffffffffff R15: 00007fff60bc55c0
 </TASK>

Allocated by task 30756:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 device_add+0xbe/0xb50
 netdev_register_kobject+0x178/0x310
 register_netdevice+0x126c/0x1ae0
 tun_set_iff+0x844/0xef0
 __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 30753:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 kobject_put+0x22b/0x480
 netdev_run_todo+0xd2e/0xea0
 tun_chr_close+0x13c/0x1c0
 __fput+0x44c/0xa70
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888026bebc00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff888026bebc00, ffff888026bebe00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888026beb400 pfn:0x26be8
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 ffffea0000a42710 ffffea0000a08410
raw: ffff888026beb400 000000000010000a 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea0000a42710 ffffea0000a08410
head: ffff888026beb400 000000000010000a 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00009afa01 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 3395, tgid 3395 (kworker/u9:3), ts 283753988532, free_ts 276330138754
 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_noprof+0x305/0x4f0
 fib6_info_alloc+0x30/0xf0
 ip6_route_info_create+0x142/0x860
 addrconf_f6i_alloc+0x1d2/0x450
 ipv6_add_addr+0x56e/0x1090
 addrconf_add_linklocal+0x28c/0x6c0
 addrconf_addr_gen+0x490/0x580
 addrconf_init_auto_addrs+0x62d/0xa30
 addrconf_notify+0xacc/0x1010
 notifier_call_chain+0x1b6/0x3e0
page last free pid 5591 tgid 5591 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __put_partials+0x156/0x1a0
 put_cpu_partial+0x17c/0x250
 __slab_free+0x2d5/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 __kmalloc_node_track_caller_noprof+0x216/0x4e0
 kmalloc_reserve+0x136/0x290
 __alloc_skb+0x142/0x2d0
 alloc_skb_with_frags+0xca/0x890
 sock_alloc_send_pskb+0x857/0x990
 unix_dgram_sendmsg+0x461/0x1850
 __sock_sendmsg+0x21c/0x270
 sock_write_iter+0x258/0x330
 vfs_write+0x54b/0xa90

Memory state around the buggy address:
 ffff888026bebb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888026bebb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888026bebc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888026bebc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888026bebd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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