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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:302 [inline]
BUG: KASAN: stack-out-of-bounds in end_buffer_read_sync+0xc1/0xd0 fs/buffer.c:161
Write of size 4 at addr ffffc90002e1e340 by task kworker/u4:12/4464

CPU: 0 UID: 0 PID: 4464 Comm: kworker/u4:12 Not tainted 6.11.0-syzkaller-10669-g11a299a7933e #0
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_rootcg_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 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:302 [inline]
 end_buffer_read_sync+0xc1/0xd0 fs/buffer.c:161
 end_bio_bh_io_sync+0xbf/0x120 fs/buffer.c:2771
 blk_update_request+0x5e5/0x1160 block/blk-mq.c:923
 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1051
 loop_handle_cmd drivers/block/loop.c:1927 [inline]
 loop_process_work+0x1c10/0x2170 drivers/block/loop.c:1945
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

The buggy address belongs to the virtual mapping at
 [ffffc90002e18000, ffffc90002e21000) created by:
 copy_process+0x5d1/0x3d50 kernel/fork.c:2206

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88803fe63b40 pfn:0x3fe63
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff88803fe63b40 0000000000000000 00000001ffffffff 0000000000000000
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_NOWARN|__GFP_ZERO), pid 4808, tgid 4808 (dhcpcd), ts 117233997375, free_ts 117220720622
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 vm_area_alloc_pages mm/vmalloc.c:3568 [inline]
 __vmalloc_area_node mm/vmalloc.c:3646 [inline]
 __vmalloc_node_range_noprof+0xa2b/0x13f0 mm/vmalloc.c:3828
 alloc_thread_stack_node kernel/fork.c:314 [inline]
 dup_task_struct+0x444/0x8c0 kernel/fork.c:1115
 copy_process+0x5d1/0x3d50 kernel/fork.c:2206
 kernel_clone+0x226/0x8f0 kernel/fork.c:2787
 __do_sys_clone kernel/fork.c:2930 [inline]
 __se_sys_clone kernel/fork.c:2914 [inline]
 __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2914
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 911 tgid 911 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
 __slab_free+0x31b/0x3d0 mm/slub.c:4491
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4086 [inline]
 slab_alloc_node mm/slub.c:4135 [inline]
 kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4187
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1322 [inline]
 alloc_skb_with_frags+0xc3/0x820 net/core/skbuff.c:6612
 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2883
 sock_alloc_send_skb include/net/sock.h:1780 [inline]
 mld_newpack+0x1c3/0xa90 net/ipv6/mcast.c:1747
 add_grhead net/ipv6/mcast.c:1850 [inline]
 add_grec+0x1492/0x19a0 net/ipv6/mcast.c:1988
 mld_send_cr net/ipv6/mcast.c:2114 [inline]
 mld_ifc_work+0x691/0xd90 net/ipv6/mcast.c:2651
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147

Memory state around the buggy address:
 ffffc90002e1e200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90002e1e280: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 f2
>ffffc90002e1e300: f2 f2 f2 f2 04 f2 00 f2 f2 f2 00 00 f3 f3 f3 f3
                                           ^
 ffffc90002e1e380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90002e1e400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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