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BUG: KASAN: use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88804a58442a by task kcompactd0/38

CPU: 0 UID: 0 PID: 38 Comm: kcompactd0 Not tainted syzkaller #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 3b f4 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:ffffc900006cedd8 EFLAGS: 00000206
RAX: 1176e907ce11b200 RBX: 0000000000000000 RCX: 1176e907ce11b200
RDX: 0000000000000001 RSI: ffffffff8dba6cac RDI: ffffffff8be33680
RBP: ffffffff822e3662 R08: 0000000000000000 R09: ffffffff822e3662
R10: dffffc0000000000 R11: fffff9400008d187 R12: 0000000000000002
R13: ffffffff8e139ee0 R14: 0000000000000000 R15: 0000000000000246
 page_ext_get+0x3e/0x2f0
 __reset_page_owner+0x28/0x1f0
 __free_frozen_pages+0xbc4/0xd30
 __folio_put+0x21b/0x2c0
 migrate_pages_batch+0x227f/0x35c0
 migrate_pages+0x1bcc/0x2930
 compact_zone+0x23e1/0x4ab0
 compact_node+0x1d2/0x280
 kcompactd+0xbc8/0x1290
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88804a586400 pfn:0x4a584
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff88804a586400 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5845, tgid 5845 (syz-executor), ts 301425268967, free_ts 308333246145
 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
 kmem_cache_alloc_noprof+0x283/0x3c0
 getname_flags+0xb8/0x540
 __x64_sys_unlink+0x3a/0x50
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 19759 tgid 19759 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __slab_free+0x303/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 getname_flags+0xb8/0x540
 vfs_fstatat+0x43/0x170
 __x64_sys_newfstatat+0x116/0x190
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804a584300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804a584380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88804a584400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                  ^
 ffff88804a584480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804a584500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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