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BUG: KASAN: stack-out-of-bounds in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: stack-out-of-bounds in atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline]
BUG: KASAN: stack-out-of-bounds in put_bh include/linux/buffer_head.h:304 [inline]
BUG: KASAN: stack-out-of-bounds in end_buffer_read_sync+0xc3/0xe0 fs/buffer.c:161
Write of size 4 at addr ffffc9000d7b64c0 by task kworker/u4:7/1039

CPU: 0 UID: 0 PID: 1039 Comm: kworker/u4:7 Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline]
 put_bh include/linux/buffer_head.h:304 [inline]
 end_buffer_read_sync+0xc3/0xe0 fs/buffer.c:161
 end_bio_bh_io_sync+0xbd/0x120 fs/buffer.c:2783
 blk_update_request+0x5eb/0xe70 block/blk-mq.c:987
 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1149
 lo_rw_aio_complete drivers/block/loop.c:328 [inline]
 lo_rw_aio+0xe0b/0x1040 drivers/block/loop.c:402
 do_req_filebacked drivers/block/loop.c:-1 [inline]
 loop_handle_cmd drivers/block/loop.c:1890 [inline]
 loop_process_work+0x810/0xf40 drivers/block/loop.c:1925
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

The buggy address belongs to the virtual mapping at
 [ffffc9000d7b0000, ffffc9000d7b9000) created by:
 copy_process+0x54b/0x3c00 kernel/fork.c:1999

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804436cfc0 pfn:0x4436c
memcg:ffff888043d27602
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff88804436cfc0 0000000000000000 00000001ffffffff ffff888043d27602
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 1039, tgid 1039 (kworker/u4:7), ts 72109218401, free_ts 72084921765
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_frozen_pages_noprof mm/mempolicy.c:2490 [inline]
 alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2510
 vm_area_alloc_pages mm/vmalloc.c:3634 [inline]
 __vmalloc_area_node mm/vmalloc.c:3712 [inline]
 __vmalloc_node_range_noprof+0x97d/0x12f0 mm/vmalloc.c:3885
 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3948
 alloc_thread_stack_node kernel/fork.c:317 [inline]
 dup_task_struct+0x3e7/0x860 kernel/fork.c:877
 copy_process+0x54b/0x3c00 kernel/fork.c:1999
 kernel_clone+0x21e/0x870 kernel/fork.c:2599
 user_mode_thread+0xdd/0x140 kernel/fork.c:2677
 call_usermodehelper_exec_sync kernel/umh.c:132 [inline]
 call_usermodehelper_exec_work+0x9c/0x230 kernel/umh.c:163
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
page last free pid 5302 tgid 5302 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 __slab_free+0x326/0x400 mm/slub.c:4554
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4249
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660
 netlink_sendmsg+0x5c6/0xb30 net/netlink/af_netlink.c:1858
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffffc9000d7b6380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000d7b6400: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>ffffc9000d7b6480: 04 f2 00 00 00 f2 f2 f2 f2 f2 00 f2 f2 f2 00 00
                                           ^
 ffffc9000d7b6500: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000d7b6580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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