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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88803736442a by task syz.0.4339/18376

CPU: 0 UID: 0 PID: 18376 Comm: syz.0.4339 Not tainted 6.16.0-rc6-syzkaller-00135-gcf074eca0065-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/0x230
 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:trace_kmem_cache_alloc+0x9/0xc0
Code: df 48 c7 c6 70 77 9e 8d e8 34 15 ef ff 90 0f 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 90 65 8b 05 7b 85 88 10 <83> f8 08 73 24 89 c0 48 0f a3 05 28 8c 8a 0d 73 12 e8 91 e1 8f ff
RSP: 0018:ffffc900083c7c50 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888109fe1d90 RCX: 0000000000000dc0
RDX: ffff88801c2a6dc0 RSI: ffff888109fe1d90 RDI: ffffffff81c18aaa
RBP: 0000000000000dc0 R08: 00000000ffffffff R09: 0000000000000000
R10: ffff888109fe1d90 R11: ffffffff81ad0050 R12: 0000000000000230
R13: ffff888109fe1d90 R14: ffff88801c2a6dc0 R15: 0000000000005100
 kmem_cache_alloc_noprof+0x21a/0x3c0
 taskstats_exit+0x14a/0xa30
 do_exit+0x630/0x22e0
 do_group_exit+0x21c/0x2d0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x21ba/0x21c0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4089b8e9a9
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:00007ffdb98408c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4089b8e9a9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffdb984092c R08: 00000019b98409bf R09: 00000000000927c0
R10: 00000000000001a4 R11: 0000000000000246 R12: 0000000000000568
R13: 00000000000927c0 R14: 000000000004951e R15: 00007ffdb9840980
 </TASK>

Allocated by task 17753:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_noprof+0x27a/0x4f0
 copy_splice_read+0x143/0x9b0
 splice_direct_to_actor+0x4d0/0xcc0
 do_splice_direct+0x181/0x270
 do_sendfile+0x4da/0x7e0
 __se_sys_sendfile64+0x13e/0x190
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 17753:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x62/0x70
 kfree+0x18e/0x440
 copy_splice_read+0x881/0x9b0
 splice_direct_to_actor+0x4d0/0xcc0
 do_splice_direct+0x181/0x270
 do_sendfile+0x4da/0x7e0
 __se_sys_sendfile64+0x13e/0x190
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888037364400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff888037364400, ffff888037364600)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888037364c00 pfn:0x37364
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 ffffea0000ddd410 ffffea0000ddd610
raw: ffff888037364c00 000000000010000b 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea0000ddd410 ffffea0000ddd610
head: ffff888037364c00 000000000010000b 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000dcd901 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 7833, tgid 7832 (syz.0.619), ts 90631442233, free_ts 68117276197
 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
 __genradix_ptr_alloc+0x352/0x4a0
 __genradix_prealloc+0x44/0x90
 sctp_stream_init+0x14b/0x440
 sctp_association_new+0x10dd/0x25f0
 sctp_connect_new_asoc+0x2c5/0x690
 sctp_sendmsg+0x155c/0x2810
 __sock_sendmsg+0x19c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
page last free pid 791 tgid 791 stack trace:
 __free_frozen_pages+0xc71/0xe70
 vfree+0x25a/0x400
 delayed_vfree_work+0x55/0x80
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30

Memory state around the buggy address:
 ffff888037364300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888037364380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888037364400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888037364480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888037364500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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