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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88810a01502a by task syz.1.3825/19867

CPU: 0 UID: 0 PID: 19867 Comm: syz.1.3825 Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10-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:exit_tasks_rcu_start+0x12/0x290
Code: 7d 7d 00 4c 89 f7 eb b6 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 18 <49> bd 00 00 00 00 00 fc ff df 65 4c 8b 34 25 08 00 9a 92 49 8d 9e
RSP: 0018:ffffc90006847a90 EFLAGS: 00000286
RAX: ffff88802f4d5248 RBX: ffff88802f4d3980 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802f4d5260
RBP: ffffc90006847c30 R08: ffff88802f4d525f R09: 0000000000000000
R10: ffff88802f4d5248 R11: ffffed1005e9aa4c R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 do_exit+0x6d2/0x22e0
 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: 0033:0x7f01ea58eb69
Code: Unable to access opcode bytes at 0x7f01ea58eb3f.
RSP: 002b:00007f01eb3cc0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f01ea7b5fa8 RCX: 00007f01ea58eb69
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f01ea7b5fa8
RBP: 00007f01ea7b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f01ea7b5fac
R13: 0000000000000000 R14: 00007fffc7d44450 R15: 00007fffc7d44538
 </TASK>

Allocated by task 19240:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 ip_vs_stats_alloc+0x50/0x180
 ip_vs_est_add_kthread+0x3de/0x700
 ip_vs_start_estimator+0x1ed/0x360
 ip_vs_control_net_init+0x138d/0x1900
 __ip_vs_init+0x2d2/0x460
 ops_init+0x35c/0x5c0
 setup_net+0x10c/0x320
 copy_net_ns+0x31b/0x4d0
 create_new_namespaces+0x3f3/0x720
 unshare_nsproxy_namespaces+0x11c/0x170
 ksys_unshare+0x4c8/0x8c0
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5826:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x62/0x70
 kfree+0x18e/0x440
 ip_vs_stop_estimator+0xa4f/0xec0
 ip_vs_control_net_cleanup+0x269/0x3e0
 __ip_vs_cleanup_batch+0x8b/0x100
 ops_undo_list+0x525/0x990
 cleanup_net+0x4c5/0x800
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30

The buggy address belongs to the object at ffff88810a015000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff88810a015000, ffff88810a015200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810a014800 pfn:0x10a014
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000240(workingset|head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000240 ffff88801a441c80 ffffea000443ce10 ffffea000439c110
raw: ffff88810a014800 0000000000100006 00000000f5000000 0000000000000000
head: 057ff00000000240 ffff88801a441c80 ffffea000443ce10 ffffea000439c110
head: ffff88810a014800 0000000000100006 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea0004280501 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5863, tgid 5863 (kworker/u8:5), ts 48016667428, free_ts 47764068031
 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/0x3b0
 ___slab_alloc+0xbfc/0x1480
 __kmalloc_cache_noprof+0x296/0x3d0
 batadv_forw_packet_alloc+0x1e9/0x390
 batadv_iv_ogm_queue_add+0x85f/0xd30
 batadv_iv_ogm_schedule+0x866/0xf00
 batadv_iv_send_outstanding_bat_ogm_packet+0x6c6/0x7e0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
page last free pid 5814 tgid 5814 stack trace:
 __free_frozen_pages+0xc71/0xe70
 __slab_free+0x326/0x400
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 __kmalloc_cache_noprof+0x1be/0x3d0
 netdevice_event+0x3a1/0x8a0
 notifier_call_chain+0x1b6/0x3e0
 netif_set_mac_address+0x37c/0x4c0
 do_setlink+0x88c/0x41c0
 rtnl_newlink+0x160b/0x1c70
 rtnetlink_rcv_msg+0x7cf/0xb70
 netlink_rcv_skb+0x208/0x470
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270

Memory state around the buggy address:
 ffff88810a014f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88810a014f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88810a015000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88810a015080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810a015100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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