==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_bh include/linux/spinlock_api_smp.h:150 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:182
Read of size 1 at addr ffff88802a2e75a0 by task syz.5.94/6166

CPU: 0 UID: 0 PID: 6166 Comm: syz.5.94 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 __kasan_check_byte+0x36/0x50 mm/kasan/common.c:574
 kasan_check_byte include/linux/kasan.h:402 [inline]
 lock_acquire kernel/locking/lockdep.c:5842 [inline]
 lock_acquire+0x132/0x370 kernel/locking/lockdep.c:5825
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:182
 spin_lock_bh include/linux/spinlock.h:348 [inline]
 bt_accept_unlink+0x64/0x370 net/bluetooth/af_bluetooth.c:262
 l2cap_sock_teardown_cb+0x1a3/0x3f0 net/bluetooth/l2cap_sock.c:1710
 l2cap_chan_del+0xa6/0x920 net/bluetooth/l2cap_core.c:687
 l2cap_conn_del+0x34f/0x6b0 net/bluetooth/l2cap_core.c:1825
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7601 [inline]
 l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7594
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline]
 hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2735
 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5513
 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:499
 hci_unregister_dev+0x23f/0x690 net/bluetooth/hci_core.c:2678
 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:700
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x951/0x2ae0 kernel/exit.c:1009
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1152
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3046
 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 00fb:0x294e66b3c7c44cb4
Code: Unable to access opcode bytes at 0x294e66b3c7c44c8a.
RSP: 002b:0000000000000000 EFLAGS: 00000202 ORIG_RAX: ce3d5c200518e753
RAX: 6d02b596a6d6b2c6 RBX: 46b00e13ac8c17fa RCX: 1d6d567492f1521e
RDX: eb30e365dd53f3a0 RSI: c553273f825e1cf7 RDI: b331ef28487276fd
RBP: 9c8c87e20081ee76 R08: cf9d780a350b4549 R09: c7e58b697db8ef3d
R10: d68d02d45a22dc24 R11: 19b4d49ef33da9ed R12: 39cb75b6fa6cb3d1
R13: a8d7b5dbf29d588f R14: 9b8908dcbb4f02b4 R15: 107b9d1451766018
 </TASK>

Allocated by task 11662:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5334 [inline]
 __kmalloc_noprof+0x322/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 sk_prot_alloc+0x10b/0x2a0 net/core/sock.c:2252
 sk_alloc+0x36/0xe80 net/core/sock.c:2308
 __netlink_create+0x5e/0x2c0 net/netlink/af_netlink.c:627
 netlink_create+0x29b/0x610 net/netlink/af_netlink.c:685
 __sock_create+0x339/0x860 net/socket.c:1651
 sock_create net/socket.c:1709 [inline]
 __sys_socket_create net/socket.c:1746 [inline]
 __sys_socket+0x14d/0x260 net/socket.c:1793
 __do_sys_socket net/socket.c:1807 [inline]
 __se_sys_socket net/socket.c:1805 [inline]
 __x64_sys_socket+0x72/0xb0 net/socket.c:1805
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 11656:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x22b/0x6c0 mm/slub.c:6692
 sk_prot_free net/core/sock.c:2291 [inline]
 __sk_destruct+0x88c/0xab0 net/core/sock.c:2391
 sk_destruct+0xc8/0xf0 net/core/sock.c:2419
 __sk_free+0xf4/0x3e0 net/core/sock.c:2430
 sk_free+0x61/0x90 net/core/sock.c:2441
 deferred_put_nlk_sk+0xbe/0x110 net/netlink/af_netlink.c:715
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2897
 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674

Last potentially related work creation:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3159
 netlink_release+0xb38/0x1ff0 net/netlink/af_netlink.c:797
 __sock_release+0xb3/0x260 net/socket.c:710
 sock_close+0x1c/0x30 net/socket.c:1501
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802a2e7000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1440 bytes inside of
 freed 2048-byte region [ffff88802a2e7000, ffff88802a2e7800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a2e7000 pfn:0x2a2e0
head: order:3 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 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
raw: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
head: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7942533759, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 refill_objects+0xe3/0x410 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 __tty_alloc_driver drivers/tty/tty_io.c:3355 [inline]
 __tty_alloc_driver+0x2d4/0x4a0 drivers/tty/tty_io.c:3326
 acm_init+0x1c/0x310 drivers/usb/class/cdc-acm.c:2142
 do_one_initcall+0x11d/0x700 init/main.c:1347
 do_initcall_level init/main.c:1409 [inline]
 do_initcalls init/main.c:1425 [inline]
 do_basic_setup init/main.c:1445 [inline]
 kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658
 kernel_init+0x1f/0x1e0 init/main.c:1548
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88802a2e7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a2e7580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88802a2e7600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
BUG: KASAN: slab-use-after-free in do_raw_spin_lock+0x23b/0x260 kernel/locking/spinlock_debug.c:115
Read of size 4 at addr ffff88802a2e758c by task syz.5.94/6166

CPU: 0 UID: 0 PID: 6166 Comm: syz.5.94 Tainted: G    B        L      syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
 do_raw_spin_lock+0x23b/0x260 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:348 [inline]
 bt_accept_unlink+0x64/0x370 net/bluetooth/af_bluetooth.c:262
 l2cap_sock_teardown_cb+0x1a3/0x3f0 net/bluetooth/l2cap_sock.c:1710
 l2cap_chan_del+0xa6/0x920 net/bluetooth/l2cap_core.c:687
 l2cap_conn_del+0x34f/0x6b0 net/bluetooth/l2cap_core.c:1825
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7601 [inline]
 l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7594
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline]
 hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2735
 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5513
 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:499
 hci_unregister_dev+0x23f/0x690 net/bluetooth/hci_core.c:2678
 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:700
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x951/0x2ae0 kernel/exit.c:1009
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1152
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3046
 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 00fb:0x294e66b3c7c44cb4
Code: Unable to access opcode bytes at 0x294e66b3c7c44c8a.
RSP: 002b:0000000000000000 EFLAGS: 00000202 ORIG_RAX: ce3d5c200518e753
RAX: 6d02b596a6d6b2c6 RBX: 46b00e13ac8c17fa RCX: 1d6d567492f1521e
RDX: eb30e365dd53f3a0 RSI: c553273f825e1cf7 RDI: b331ef28487276fd
RBP: 9c8c87e20081ee76 R08: cf9d780a350b4549 R09: c7e58b697db8ef3d
R10: d68d02d45a22dc24 R11: 19b4d49ef33da9ed R12: 39cb75b6fa6cb3d1
R13: a8d7b5dbf29d588f R14: 9b8908dcbb4f02b4 R15: 107b9d1451766018
 </TASK>

Allocated by task 11662:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5334 [inline]
 __kmalloc_noprof+0x322/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 sk_prot_alloc+0x10b/0x2a0 net/core/sock.c:2252
 sk_alloc+0x36/0xe80 net/core/sock.c:2308
 __netlink_create+0x5e/0x2c0 net/netlink/af_netlink.c:627
 netlink_create+0x29b/0x610 net/netlink/af_netlink.c:685
 __sock_create+0x339/0x860 net/socket.c:1651
 sock_create net/socket.c:1709 [inline]
 __sys_socket_create net/socket.c:1746 [inline]
 __sys_socket+0x14d/0x260 net/socket.c:1793
 __do_sys_socket net/socket.c:1807 [inline]
 __se_sys_socket net/socket.c:1805 [inline]
 __x64_sys_socket+0x72/0xb0 net/socket.c:1805
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 11656:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x22b/0x6c0 mm/slub.c:6692
 sk_prot_free net/core/sock.c:2291 [inline]
 __sk_destruct+0x88c/0xab0 net/core/sock.c:2391
 sk_destruct+0xc8/0xf0 net/core/sock.c:2419
 __sk_free+0xf4/0x3e0 net/core/sock.c:2430
 sk_free+0x61/0x90 net/core/sock.c:2441
 deferred_put_nlk_sk+0xbe/0x110 net/netlink/af_netlink.c:715
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2897
 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674

Last potentially related work creation:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3159
 netlink_release+0xb38/0x1ff0 net/netlink/af_netlink.c:797
 __sock_release+0xb3/0x260 net/socket.c:710
 sock_close+0x1c/0x30 net/socket.c:1501
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802a2e7000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1420 bytes inside of
 freed 2048-byte region [ffff88802a2e7000, ffff88802a2e7800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a2e7000 pfn:0x2a2e0
head: order:3 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 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
raw: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
head: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7942533759, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 refill_objects+0xe3/0x410 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 __tty_alloc_driver drivers/tty/tty_io.c:3355 [inline]
 __tty_alloc_driver+0x2d4/0x4a0 drivers/tty/tty_io.c:3326
 acm_init+0x1c/0x310 drivers/usb/class/cdc-acm.c:2142
 do_one_initcall+0x11d/0x700 init/main.c:1347
 do_initcall_level init/main.c:1409 [inline]
 do_initcalls init/main.c:1425 [inline]
 do_basic_setup init/main.c:1445 [inline]
 kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658
 kernel_init+0x1f/0x1e0 init/main.c:1548
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88802a2e7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a2e7580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88802a2e7600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:87 [inline]
BUG: KASAN: slab-use-after-free in do_raw_spin_lock+0x248/0x260 kernel/locking/spinlock_debug.c:115
Read of size 8 at addr ffff88802a2e7598 by task syz.5.94/6166

CPU: 0 UID: 0 PID: 6166 Comm: syz.5.94 Tainted: G    B        L      syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 debug_spin_lock_before kernel/locking/spinlock_debug.c:87 [inline]
 do_raw_spin_lock+0x248/0x260 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:348 [inline]
 bt_accept_unlink+0x64/0x370 net/bluetooth/af_bluetooth.c:262
 l2cap_sock_teardown_cb+0x1a3/0x3f0 net/bluetooth/l2cap_sock.c:1710
 l2cap_chan_del+0xa6/0x920 net/bluetooth/l2cap_core.c:687
 l2cap_conn_del+0x34f/0x6b0 net/bluetooth/l2cap_core.c:1825
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7601 [inline]
 l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7594
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline]
 hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2735
 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5513
 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:499
 hci_unregister_dev+0x23f/0x690 net/bluetooth/hci_core.c:2678
 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:700
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x951/0x2ae0 kernel/exit.c:1009
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1152
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3046
 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 00fb:0x294e66b3c7c44cb4
Code: Unable to access opcode bytes at 0x294e66b3c7c44c8a.
RSP: 002b:0000000000000000 EFLAGS: 00000202 ORIG_RAX: ce3d5c200518e753
RAX: 6d02b596a6d6b2c6 RBX: 46b00e13ac8c17fa RCX: 1d6d567492f1521e
RDX: eb30e365dd53f3a0 RSI: c553273f825e1cf7 RDI: b331ef28487276fd
RBP: 9c8c87e20081ee76 R08: cf9d780a350b4549 R09: c7e58b697db8ef3d
R10: d68d02d45a22dc24 R11: 19b4d49ef33da9ed R12: 39cb75b6fa6cb3d1
R13: a8d7b5dbf29d588f R14: 9b8908dcbb4f02b4 R15: 107b9d1451766018
 </TASK>

Allocated by task 11662:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5334 [inline]
 __kmalloc_noprof+0x322/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 sk_prot_alloc+0x10b/0x2a0 net/core/sock.c:2252
 sk_alloc+0x36/0xe80 net/core/sock.c:2308
 __netlink_create+0x5e/0x2c0 net/netlink/af_netlink.c:627
 netlink_create+0x29b/0x610 net/netlink/af_netlink.c:685
 __sock_create+0x339/0x860 net/socket.c:1651
 sock_create net/socket.c:1709 [inline]
 __sys_socket_create net/socket.c:1746 [inline]
 __sys_socket+0x14d/0x260 net/socket.c:1793
 __do_sys_socket net/socket.c:1807 [inline]
 __se_sys_socket net/socket.c:1805 [inline]
 __x64_sys_socket+0x72/0xb0 net/socket.c:1805
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 11656:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x22b/0x6c0 mm/slub.c:6692
 sk_prot_free net/core/sock.c:2291 [inline]
 __sk_destruct+0x88c/0xab0 net/core/sock.c:2391
 sk_destruct+0xc8/0xf0 net/core/sock.c:2419
 __sk_free+0xf4/0x3e0 net/core/sock.c:2430
 sk_free+0x61/0x90 net/core/sock.c:2441
 deferred_put_nlk_sk+0xbe/0x110 net/netlink/af_netlink.c:715
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2897
 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674

Last potentially related work creation:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3159
 netlink_release+0xb38/0x1ff0 net/netlink/af_netlink.c:797
 __sock_release+0xb3/0x260 net/socket.c:710
 sock_close+0x1c/0x30 net/socket.c:1501
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802a2e7000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1432 bytes inside of
 freed 2048-byte region [ffff88802a2e7000, ffff88802a2e7800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a2e7000 pfn:0x2a2e0
head: order:3 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 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
raw: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
head: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7942533759, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 refill_objects+0xe3/0x410 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 __tty_alloc_driver drivers/tty/tty_io.c:3355 [inline]
 __tty_alloc_driver+0x2d4/0x4a0 drivers/tty/tty_io.c:3326
 acm_init+0x1c/0x310 drivers/usb/class/cdc-acm.c:2142
 do_one_initcall+0x11d/0x700 init/main.c:1347
 do_initcall_level init/main.c:1409 [inline]
 do_initcalls init/main.c:1425 [inline]
 do_basic_setup init/main.c:1445 [inline]
 kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658
 kernel_init+0x1f/0x1e0 init/main.c:1548
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88802a2e7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a2e7580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff88802a2e7600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:88 [inline]
BUG: KASAN: slab-use-after-free in do_raw_spin_lock+0x231/0x260 kernel/locking/spinlock_debug.c:115
Read of size 4 at addr ffff88802a2e7590 by task syz.5.94/6166

CPU: 0 UID: 0 PID: 6166 Comm: syz.5.94 Tainted: G    B        L      syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 debug_spin_lock_before kernel/locking/spinlock_debug.c:88 [inline]
 do_raw_spin_lock+0x231/0x260 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:348 [inline]
 bt_accept_unlink+0x64/0x370 net/bluetooth/af_bluetooth.c:262
 l2cap_sock_teardown_cb+0x1a3/0x3f0 net/bluetooth/l2cap_sock.c:1710
 l2cap_chan_del+0xa6/0x920 net/bluetooth/l2cap_core.c:687
 l2cap_conn_del+0x34f/0x6b0 net/bluetooth/l2cap_core.c:1825
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7601 [inline]
 l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7594
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline]
 hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2735
 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5513
 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:499
 hci_unregister_dev+0x23f/0x690 net/bluetooth/hci_core.c:2678
 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:700
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x951/0x2ae0 kernel/exit.c:1009
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1152
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3046
 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 00fb:0x294e66b3c7c44cb4
Code: Unable to access opcode bytes at 0x294e66b3c7c44c8a.
RSP: 002b:0000000000000000 EFLAGS: 00000202 ORIG_RAX: ce3d5c200518e753
RAX: 6d02b596a6d6b2c6 RBX: 46b00e13ac8c17fa RCX: 1d6d567492f1521e
RDX: eb30e365dd53f3a0 RSI: c553273f825e1cf7 RDI: b331ef28487276fd
RBP: 9c8c87e20081ee76 R08: cf9d780a350b4549 R09: c7e58b697db8ef3d
R10: d68d02d45a22dc24 R11: 19b4d49ef33da9ed R12: 39cb75b6fa6cb3d1
R13: a8d7b5dbf29d588f R14: 9b8908dcbb4f02b4 R15: 107b9d1451766018
 </TASK>

Allocated by task 11662:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5334 [inline]
 __kmalloc_noprof+0x322/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 sk_prot_alloc+0x10b/0x2a0 net/core/sock.c:2252
 sk_alloc+0x36/0xe80 net/core/sock.c:2308
 __netlink_create+0x5e/0x2c0 net/netlink/af_netlink.c:627
 netlink_create+0x29b/0x610 net/netlink/af_netlink.c:685
 __sock_create+0x339/0x860 net/socket.c:1651
 sock_create net/socket.c:1709 [inline]
 __sys_socket_create net/socket.c:1746 [inline]
 __sys_socket+0x14d/0x260 net/socket.c:1793
 __do_sys_socket net/socket.c:1807 [inline]
 __se_sys_socket net/socket.c:1805 [inline]
 __x64_sys_socket+0x72/0xb0 net/socket.c:1805
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 11656:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x22b/0x6c0 mm/slub.c:6692
 sk_prot_free net/core/sock.c:2291 [inline]
 __sk_destruct+0x88c/0xab0 net/core/sock.c:2391
 sk_destruct+0xc8/0xf0 net/core/sock.c:2419
 __sk_free+0xf4/0x3e0 net/core/sock.c:2430
 sk_free+0x61/0x90 net/core/sock.c:2441
 deferred_put_nlk_sk+0xbe/0x110 net/netlink/af_netlink.c:715
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2897
 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674

Last potentially related work creation:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3159
 netlink_release+0xb38/0x1ff0 net/netlink/af_netlink.c:797
 __sock_release+0xb3/0x260 net/socket.c:710
 sock_close+0x1c/0x30 net/socket.c:1501
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802a2e7000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1424 bytes inside of
 freed 2048-byte region [ffff88802a2e7000, ffff88802a2e7800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a2e7000 pfn:0x2a2e0
head: order:3 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 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
raw: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
head: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7942533759, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 refill_objects+0xe3/0x410 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 __tty_alloc_driver drivers/tty/tty_io.c:3355 [inline]
 __tty_alloc_driver+0x2d4/0x4a0 drivers/tty/tty_io.c:3326
 acm_init+0x1c/0x310 drivers/usb/class/cdc-acm.c:2142
 do_one_initcall+0x11d/0x700 init/main.c:1347
 do_initcall_level init/main.c:1409 [inline]
 do_initcalls init/main.c:1425 [inline]
 do_basic_setup init/main.c:1445 [inline]
 kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658
 kernel_init+0x1f/0x1e0 init/main.c:1548
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88802a2e7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a2e7580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88802a2e7600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:112 [inline]
BUG: KASAN: slab-use-after-free in atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline]
BUG: KASAN: slab-use-after-free in queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
BUG: KASAN: slab-use-after-free in do_raw_spin_lock+0x119/0x260 kernel/locking/spinlock_debug.c:116
Write of size 4 at addr ffff88802a2e7588 by task syz.5.94/6166

CPU: 0 UID: 0 PID: 6166 Comm: syz.5.94 Tainted: G    B        L      syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:186 [inline]
 kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200
 instrument_atomic_read_write include/linux/instrumented.h:112 [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+0x119/0x260 kernel/locking/spinlock_debug.c:116
 spin_lock_bh include/linux/spinlock.h:348 [inline]
 bt_accept_unlink+0x64/0x370 net/bluetooth/af_bluetooth.c:262
 l2cap_sock_teardown_cb+0x1a3/0x3f0 net/bluetooth/l2cap_sock.c:1710
 l2cap_chan_del+0xa6/0x920 net/bluetooth/l2cap_core.c:687
 l2cap_conn_del+0x34f/0x6b0 net/bluetooth/l2cap_core.c:1825
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7601 [inline]
 l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7594
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline]
 hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2735
 hci_dev_close_sync+0x5cf/0x13c0 net/bluetooth/hci_sync.c:5513
 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:499
 hci_unregister_dev+0x23f/0x690 net/bluetooth/hci_core.c:2678
 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:700
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x951/0x2ae0 kernel/exit.c:1009
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1152
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3046
 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x139/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 00fb:0x294e66b3c7c44cb4
Code: Unable to access opcode bytes at 0x294e66b3c7c44c8a.
RSP: 002b:0000000000000000 EFLAGS: 00000202 ORIG_RAX: ce3d5c200518e753
RAX: 6d02b596a6d6b2c6 RBX: 46b00e13ac8c17fa RCX: 1d6d567492f1521e
RDX: eb30e365dd53f3a0 RSI: c553273f825e1cf7 RDI: b331ef28487276fd
RBP: 9c8c87e20081ee76 R08: cf9d780a350b4549 R09: c7e58b697db8ef3d
R10: d68d02d45a22dc24 R11: 19b4d49ef33da9ed R12: 39cb75b6fa6cb3d1
R13: a8d7b5dbf29d588f R14: 9b8908dcbb4f02b4 R15: 107b9d1451766018
 </TASK>

Allocated by task 11662:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5334 [inline]
 __kmalloc_noprof+0x322/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 sk_prot_alloc+0x10b/0x2a0 net/core/sock.c:2252
 sk_alloc+0x36/0xe80 net/core/sock.c:2308
 __netlink_create+0x5e/0x2c0 net/netlink/af_netlink.c:627
 netlink_create+0x29b/0x610 net/netlink/af_netlink.c:685
 __sock_create+0x339/0x860 net/socket.c:1651
 sock_create net/socket.c:1709 [inline]
 __sys_socket_create net/socket.c:1746 [inline]
 __sys_socket+0x14d/0x260 net/socket.c:1793
 __do_sys_socket net/socket.c:1807 [inline]
 __se_sys_socket net/socket.c:1805 [inline]
 __x64_sys_socket+0x72/0xb0 net/socket.c:1805
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 11656:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x22b/0x6c0 mm/slub.c:6692
 sk_prot_free net/core/sock.c:2291 [inline]
 __sk_destruct+0x88c/0xab0 net/core/sock.c:2391
 sk_destruct+0xc8/0xf0 net/core/sock.c:2419
 __sk_free+0xf4/0x3e0 net/core/sock.c:2430
 sk_free+0x61/0x90 net/core/sock.c:2441
 deferred_put_nlk_sk+0xbe/0x110 net/netlink/af_netlink.c:715
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2897
 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674

Last potentially related work creation:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3159
 netlink_release+0xb38/0x1ff0 net/netlink/af_netlink.c:797
 __sock_release+0xb3/0x260 net/socket.c:710
 sock_close+0x1c/0x30 net/socket.c:1501
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1d8/0x6f0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802a2e7000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1416 bytes inside of
 freed 2048-byte region [ffff88802a2e7000, ffff88802a2e7800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a2e7000 pfn:0x2a2e0
head: order:3 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 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
raw: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe22000 ffffea0000ad4610 ffffea0000b35a10
head: ffff88802a2e7000 0000000800080004 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7942533759, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 refill_objects+0xe3/0x410 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 __tty_alloc_driver drivers/tty/tty_io.c:3355 [inline]
 __tty_alloc_driver+0x2d4/0x4a0 drivers/tty/tty_io.c:3326
 acm_init+0x1c/0x310 drivers/usb/class/cdc-acm.c:2142
 do_one_initcall+0x11d/0x700 init/main.c:1347
 do_initcall_level init/main.c:1409 [inline]
 do_initcalls init/main.c:1425 [inline]
 do_basic_setup init/main.c:1445 [inline]
 kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658
 kernel_init+0x1f/0x1e0 init/main.c:1548
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88802a2e7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a2e7580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88802a2e7600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a2e7680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================