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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88802a05102a by task syz.3.7122/22472

CPU: 0 UID: 0 PID: 22472 Comm: syz.3.7122 Not tainted 6.16.0-syzkaller-06620-gae633388cae3-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:alloc_buddy_hugetlb_folio+0x100/0x1c0
Code: 48 8b 0c 24 e8 e1 64 f7 ff 48 85 c0 0f 94 c1 45 08 ef 41 08 cf 74 27 48 85 c0 0f 95 c1 48 85 db 0f 94 c2 41 80 f5 01 41 08 d5 <41> 08 cd 74 4a 48 85 c0 74 72 49 89 c7 e8 1e 58 a1 ff eb 2e 49 89
RSP: 0018:ffffc90002a6f3c8 EFLAGS: 00000202
RAX: ffffea0000e80000 RBX: 0000000000000000 RCX: d3ccb8150182b301
RDX: 0000000000000001 RSI: ffffffff8be309e0 RDI: ffffffff8be309a0
RBP: 0000000000146cca R08: ffffffff8fa07bf7 R09: 1ffffffff1f40f7e
R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: 0000000000000009
R13: 0000000000000001 R14: 0000000000000000 R15: dffffc0000000001
 only_alloc_fresh_hugetlb_folio+0x8c/0x280
 alloc_surplus_hugetlb_folio+0x103/0x430
 hugetlb_acct_memory+0x59f/0x1050
 hugetlb_reserve_pages+0x892/0xe80
 hugetlbfs_file_mmap+0x490/0x670
 mmap_region+0x127a/0x1f30
 do_mmap+0xc45/0x10d0
 vm_mmap_pgoff+0x31b/0x4c0
 ksys_mmap_pgoff+0x587/0x760
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd563f8ebe9
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:00007fd564d69038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fd5641b5fa0 RCX: 00007fd563f8ebe9
RDX: 0000000000000000 RSI: 0000000000c00000 RDI: 0000200000000000
RBP: 00007fd564011e19 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000042073 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd5641b6038 R14: 00007fd5641b5fa0 R15: 00007ffd124938a8
 </TASK>

Allocated by task 6493:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 rose_add_node+0x23a/0xde0
 rose_rt_ioctl+0xa48/0xfb0
 rose_ioctl+0x3ce/0x8b0
 sock_do_ioctl+0xdc/0x300
 sock_ioctl+0x576/0x790
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 22120:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x62/0x70
 kfree+0x18e/0x440
 rose_rt_device_down+0x473/0x4c0
 rose_device_event+0x603/0x6a0
 notifier_call_chain+0x1b6/0x3e0
 __dev_notify_flags+0x18d/0x2e0
 netif_change_flags+0xe8/0x1a0
 dev_change_flags+0x130/0x260
 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 ffff88802a051000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff88802a051000, ffff88802a051200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a051000 pfn:0x2a050
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 ffffea0000e2a210 ffffea00008a6d10
raw: ffff88802a051000 0000000000100009 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea0000e2a210 ffffea00008a6d10
head: ffff88802a051000 0000000000100009 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000a81401 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 5819, tgid 5819 (syz-executor), ts 57492379633, free_ts 57391770979
 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_noprof+0x305/0x4f0
 fib6_info_alloc+0x30/0xf0
 ip6_route_info_create+0x142/0x860
 addrconf_f6i_alloc+0x1d2/0x450
 addrconf_permanent_addr+0x274/0x9d0
 addrconf_notify+0x887/0x1010
 notifier_call_chain+0x1b6/0x3e0
 __dev_notify_flags+0x18d/0x2e0
 netif_change_flags+0xe8/0x1a0
 do_setlink+0xc55/0x41c0
page last free pid 5819 tgid 5819 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
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 __alloc_skb+0x112/0x2d0
 netlink_ack+0x146/0xa50
 netlink_rcv_skb+0x28c/0x470
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802a050f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a050f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802a051000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88802a051080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a051100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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