==================================================================
BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:199 [inline]
BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:694 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0x1a24/0x1ca0 kernel/locking/mutex.c:776
Read of size 8 at addr ffff88802a5880a8 by task khidpd_10000008/8170

CPU: 1 UID: 0 PID: 8170 Comm: khidpd_10000008 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 __mutex_waiter_is_first kernel/locking/mutex.c:199 [inline]
 __mutex_lock_common kernel/locking/mutex.c:694 [inline]
 __mutex_lock+0x1a24/0x1ca0 kernel/locking/mutex.c:776
 l2cap_unregister_user+0x71/0x240 net/bluetooth/l2cap_core.c:1729
 hidp_session_thread+0x45e/0x680 net/bluetooth/hidp/core.c:1304
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a58ad80 pfn:0x2a588
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0000de3d08 ffff8880b85410c0 0000000000000000
raw: ffff88802a58ad80 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x40dc0(GFP_KERNEL|__GFP_ZERO|__GFP_COMP), pid 8103, tgid 8103 (syz-executor), ts 462697026380, free_ts 561863327901
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 ___kmalloc_large_node+0x10c/0x150 mm/slub.c:5598
 __kmalloc_large_node_noprof+0x1c/0x70 mm/slub.c:5629
 __do_kmalloc_node mm/slub.c:5645 [inline]
 __kmalloc_noprof.cold+0xc/0x62 mm/slub.c:5669
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 hci_alloc_dev_priv+0x1d/0x28a0 net/bluetooth/hci_core.c:2448
 hci_alloc_dev include/net/bluetooth/hci_core.h:1761 [inline]
 __vhci_create_device+0xf0/0x880 drivers/bluetooth/hci_vhci.c:421
 vhci_create_device drivers/bluetooth/hci_vhci.c:479 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:536 [inline]
 vhci_write+0x2c0/0x480 drivers/bluetooth/hci_vhci.c:616
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 8603 tgid 8595 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
 hci_release_dev+0x4ef/0x640 net/bluetooth/hci_core.c:2776
 bt_host_release+0x6a/0xb0 net/bluetooth/hci_sysfs.c:87
 device_release+0xa4/0x240 drivers/base/core.c:2565
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1ef/0x6f0 lib/kobject.c:737
 put_device+0x1f/0x30 drivers/base/core.c:3797
 vhci_release+0x185/0x230 drivers/bluetooth/hci_vhci.c:691
 __fput+0x402/0xb70 fs/file_table.c:468
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x87f/0x2bd0 kernel/exit.c:971
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
 get_signal+0x2671/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802a587f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a588000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88802a588080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                  ^
 ffff88802a588100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802a588180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
==================================================================
BUG: KASAN: use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
BUG: KASAN: use-after-free in do_raw_spin_lock+0x26f/0x2b0 kernel/locking/spinlock_debug.c:115
Read of size 4 at addr ffff88802a588064 by task khidpd_10000008/8170

CPU: 1 UID: 0 PID: 8170 Comm: khidpd_10000008 Tainted: G    B               syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
 do_raw_spin_lock+0x26f/0x2b0 kernel/locking/spinlock_debug.c:115
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162
 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
 set_task_blocked_on include/linux/sched.h:2165 [inline]
 __mutex_lock_common kernel/locking/mutex.c:701 [inline]
 __mutex_lock+0xca5/0x1ca0 kernel/locking/mutex.c:776
 l2cap_unregister_user+0x71/0x240 net/bluetooth/l2cap_core.c:1729
 hidp_session_thread+0x45e/0x680 net/bluetooth/hidp/core.c:1304
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a58ad80 pfn:0x2a588
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001db5008 ffff8880b85410c0 0000000000000000
raw: ffff88802a58ad80 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x92820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC), pid 8170, tgid 8170 (khidpd_10000008), ts 562401545631, free_ts 562401578451
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2577
 stack_depot_save_flags+0x8fe/0x9b0 lib/stackdepot.c:677
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
page last free pid 8170 tgid 8170 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
 stack_depot_save_flags+0x352/0x9b0 lib/stackdepot.c:727
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
 tcp_v4_do_rcv+0x68e/0x10a0 net/ipv4/tcp_ipv4.c:1904
 tcp_v4_rcv+0x3077/0x4db0 net/ipv4/tcp_ipv4.c:2324
 ip_protocol_deliver_rcu+0xba/0x4c0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3f2/0x720 net/ipv4/ip_input.c:241

Memory state around the buggy address:
 ffff88802a587f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a587f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802a588000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                       ^
 ffff88802a588080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802a588100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
==================================================================
BUG: KASAN: use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:87 [inline]
BUG: KASAN: use-after-free in do_raw_spin_lock+0x27f/0x2b0 kernel/locking/spinlock_debug.c:115
Read of size 8 at addr ffff88802a588070 by task khidpd_10000008/8170

CPU: 1 UID: 0 PID: 8170 Comm: khidpd_10000008 Tainted: G    B               syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 debug_spin_lock_before kernel/locking/spinlock_debug.c:87 [inline]
 do_raw_spin_lock+0x27f/0x2b0 kernel/locking/spinlock_debug.c:115
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162
 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
 set_task_blocked_on include/linux/sched.h:2165 [inline]
 __mutex_lock_common kernel/locking/mutex.c:701 [inline]
 __mutex_lock+0xca5/0x1ca0 kernel/locking/mutex.c:776
 l2cap_unregister_user+0x71/0x240 net/bluetooth/l2cap_core.c:1729
 hidp_session_thread+0x45e/0x680 net/bluetooth/hidp/core.c:1304
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a58ad80 pfn:0x2a588
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001db5008 ffff8880b85410c0 0000000000000000
raw: ffff88802a58ad80 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x92820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC), pid 8170, tgid 8170 (khidpd_10000008), ts 562401545631, free_ts 562401578451
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2577
 stack_depot_save_flags+0x8fe/0x9b0 lib/stackdepot.c:677
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
page last free pid 8170 tgid 8170 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
 stack_depot_save_flags+0x352/0x9b0 lib/stackdepot.c:727
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
 tcp_v4_do_rcv+0x68e/0x10a0 net/ipv4/tcp_ipv4.c:1904
 tcp_v4_rcv+0x3077/0x4db0 net/ipv4/tcp_ipv4.c:2324
 ip_protocol_deliver_rcu+0xba/0x4c0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3f2/0x720 net/ipv4/ip_input.c:241

Memory state around the buggy address:
 ffff88802a587f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a587f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802a588000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                             ^
 ffff88802a588080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802a588100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
==================================================================
BUG: KASAN: use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:88 [inline]
BUG: KASAN: use-after-free in do_raw_spin_lock+0x265/0x2b0 kernel/locking/spinlock_debug.c:115
Read of size 4 at addr ffff88802a588068 by task khidpd_10000008/8170

CPU: 1 UID: 0 PID: 8170 Comm: khidpd_10000008 Tainted: G    B               syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 debug_spin_lock_before kernel/locking/spinlock_debug.c:88 [inline]
 do_raw_spin_lock+0x265/0x2b0 kernel/locking/spinlock_debug.c:115
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162
 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
 set_task_blocked_on include/linux/sched.h:2165 [inline]
 __mutex_lock_common kernel/locking/mutex.c:701 [inline]
 __mutex_lock+0xca5/0x1ca0 kernel/locking/mutex.c:776
 l2cap_unregister_user+0x71/0x240 net/bluetooth/l2cap_core.c:1729
 hidp_session_thread+0x45e/0x680 net/bluetooth/hidp/core.c:1304
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a58ad80 pfn:0x2a588
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001db5008 ffff8880b85410c0 0000000000000000
raw: ffff88802a58ad80 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x92820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC), pid 8170, tgid 8170 (khidpd_10000008), ts 562401545631, free_ts 562401578451
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2577
 stack_depot_save_flags+0x8fe/0x9b0 lib/stackdepot.c:677
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
page last free pid 8170 tgid 8170 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
 stack_depot_save_flags+0x352/0x9b0 lib/stackdepot.c:727
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
 tcp_v4_do_rcv+0x68e/0x10a0 net/ipv4/tcp_ipv4.c:1904
 tcp_v4_rcv+0x3077/0x4db0 net/ipv4/tcp_ipv4.c:2324
 ip_protocol_deliver_rcu+0xba/0x4c0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3f2/0x720 net/ipv4/ip_input.c:241

Memory state around the buggy address:
 ffff88802a587f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a587f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802a588000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                          ^
 ffff88802a588080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802a588100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: use-after-free in atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline]
BUG: KASAN: use-after-free in queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
BUG: KASAN: use-after-free in do_raw_spin_lock+0x11d/0x2b0 kernel/locking/spinlock_debug.c:116
Write of size 4 at addr ffff88802a588060 by task khidpd_10000008/8170

CPU: 1 UID: 0 PID: 8170 Comm: khidpd_10000008 Tainted: G    B               syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:194 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:200
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
 do_raw_spin_lock+0x11d/0x2b0 kernel/locking/spinlock_debug.c:116
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162
 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline]
 set_task_blocked_on include/linux/sched.h:2165 [inline]
 __mutex_lock_common kernel/locking/mutex.c:701 [inline]
 __mutex_lock+0xca5/0x1ca0 kernel/locking/mutex.c:776
 l2cap_unregister_user+0x71/0x240 net/bluetooth/l2cap_core.c:1729
 hidp_session_thread+0x45e/0x680 net/bluetooth/hidp/core.c:1304
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a58ad80 pfn:0x2a588
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001db5008 ffff8880b85410c0 0000000000000000
raw: ffff88802a58ad80 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x92820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC), pid 8170, tgid 8170 (khidpd_10000008), ts 562401545631, free_ts 562401578451
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2577
 stack_depot_save_flags+0x8fe/0x9b0 lib/stackdepot.c:677
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
page last free pid 8170 tgid 8170 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
 stack_depot_save_flags+0x352/0x9b0 lib/stackdepot.c:727
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_node_noprof+0x298/0x800 mm/slub.c:5315
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:586
 __alloc_skb+0x186/0x410 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x67/0x910 net/ipv4/tcp_output.c:4437
 __tcp_send_ack net/ipv4/tcp_output.c:4470 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4470
 __tcp_ack_snd_check+0x1fe/0xa00 net/ipv4/tcp_input.c:5932
 tcp_ack_snd_check net/ipv4/tcp_input.c:5986 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:5980 [inline]
 tcp_rcv_state_process+0x1121/0x6540 net/ipv4/tcp_input.c:7193
 tcp_v4_do_rcv+0x68e/0x10a0 net/ipv4/tcp_ipv4.c:1904
 tcp_v4_rcv+0x3077/0x4db0 net/ipv4/tcp_ipv4.c:2324
 ip_protocol_deliver_rcu+0xba/0x4c0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3f2/0x720 net/ipv4/ip_input.c:241

Memory state around the buggy address:
 ffff88802a587f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a587f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802a588000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                       ^
 ffff88802a588080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802a588100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================