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BUG: KASAN: use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88803a89982a by task swapper/1/0

CPU: 1 UID: 0 PID: 0 Comm: swapper/1 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:pv_native_safe_halt+0x13/0x20
Code: 53 e8 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 13 6f 18 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000177de0 EFLAGS: 00000282
RAX: 84f900d2192a9300 RBX: ffffffff81969b18 RCX: 84f900d2192a9300
RDX: 0000000000000001 RSI: ffffffff8d9792eb RDI: ffffffff8be30a00
RBP: ffffc90000177f20 R08: ffff888136632f5b R09: 1ffff11026cc65eb
R10: dffffc0000000000 R11: ffffed1026cc65ec R12: ffffffff8fa07bf0
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110200d3000
 default_idle+0x13/0x20
 default_idle_call+0x74/0xb0
 do_idle+0x1e8/0x510
 cpu_startup_entry+0x44/0x60
 start_secondary+0x101/0x110
 common_startup_64+0x13e/0x147
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffffffffffffffff pfn:0x3a899
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x406dc2(GFP_KERNEL_ACCOUNT|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN|__GFP_RETRY_MAYFAIL), pid 24638, tgid 24635 (syz.0.8100), ts 365785736506, free_ts 366454188806
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 alloc_pages_noprof+0xa9/0x190
 __vmalloc_node_range_noprof+0x97d/0x12f0
 bpf_map_area_alloc+0x12d/0x180
 prealloc_init+0x123/0x630
 htab_map_alloc+0x6ce/0xc70
 map_create+0xaa3/0x1310
 __sys_bpf+0x60f/0x870
 __x64_sys_bpf+0x7c/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 24638 tgid 24635 stack trace:
 __free_frozen_pages+0xc71/0xe70
 vfree+0x25a/0x400
 prealloc_init+0x42e/0x630
 htab_map_alloc+0x6ce/0xc70
 map_create+0xaa3/0x1310
 __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:
 ffff88803a899700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88803a899780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88803a899800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                  ^
 ffff88803a899880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88803a899900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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