=========================
WARNING: held lock freed!
6.15.0-rc3-syzkaller-00154-g2d52e2e38b85 #0 Not tainted
-------------------------
syz.4.1263/11153 is freeing memory ffff88807fa70000-ffff88807fa707ff, with a lock still held there!
ffff88807fa70258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
ffff88807fa70258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: bt_accept_dequeue+0xfc/0x590 net/bluetooth/af_bluetooth.c:276
2 locks held by syz.4.1263/11153:
 #0: ffff88805d093808 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #0: ffff88805d093808 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
 #0: ffff88805d093808 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391
 #1: ffff88807fa70258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
 #1: ffff88807fa70258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: bt_accept_dequeue+0xfc/0x590 net/bluetooth/af_bluetooth.c:276

stack backtrace:
CPU: 0 UID: 0 PID: 11153 Comm: syz.4.1263 Not tainted 6.15.0-rc3-syzkaller-00154-g2d52e2e38b85 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_freed_lock_bug kernel/locking/lockdep.c:6682 [inline]
 debug_check_no_locks_freed+0x18b/0x1c0 kernel/locking/lockdep.c:6717
 slab_free_hook mm/slub.c:2326 [inline]
 slab_free mm/slub.c:4656 [inline]
 kfree+0x102/0x440 mm/slub.c:4855
 sk_prot_free net/core/sock.c:2237 [inline]
 __sk_destruct+0x4e1/0x660 net/core/sock.c:2332
 bt_accept_dequeue+0x3ce/0x590 net/bluetooth/af_bluetooth.c:305
 l2cap_sock_cleanup_listen+0x2f/0x3e0 net/bluetooth/l2cap_sock.c:1451
 l2cap_sock_release+0x5d/0x1d0 net/bluetooth/l2cap_sock.c:1425
 __sock_release net/socket.c:647 [inline]
 sock_close+0xc0/0x240 net/socket.c:1391
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efeb8d8e969
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:00007fff7d67e268 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007efeb8fb7ba0 RCX: 00007efeb8d8e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007efeb8fb7ba0 R08: 0000000000000140 R09: 000000137d67e55f
R10: 00007efeb8fb7ac0 R11: 0000000000000246 R12: 00000000000379e9
R13: 00007efeb8fb64e0 R14: ffffffffffffffff R15: 00007fff7d67e380
 </TASK>
==================================================================
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+0x23d/0x290 kernel/locking/spinlock_debug.c:115
Read of size 4 at addr ffff88807fa701c4 by task syz.4.1263/11153

CPU: 1 UID: 0 PID: 11153 Comm: syz.4.1263 Not tainted 6.15.0-rc3-syzkaller-00154-g2d52e2e38b85 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xb4/0x290 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
 do_raw_spin_lock+0x23d/0x290 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:356 [inline]
 release_sock+0x2f/0x1f0 net/core/sock.c:3715
 bt_accept_dequeue+0x512/0x590 net/bluetooth/af_bluetooth.c:309
 l2cap_sock_cleanup_listen+0x2f/0x3e0 net/bluetooth/l2cap_sock.c:1451
 l2cap_sock_release+0x5d/0x1d0 net/bluetooth/l2cap_sock.c:1425
 __sock_release net/socket.c:647 [inline]
 sock_close+0xc0/0x240 net/socket.c:1391
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efeb8d8e969
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:00007fff7d67e268 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007efeb8fb7ba0 RCX: 00007efeb8d8e969
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007efeb8fb7ba0 R08: 0000000000000140 R09: 000000137d67e55f
R10: 00007efeb8fb7ac0 R11: 0000000000000246 R12: 00000000000379e9
R13: 00007efeb8fb64e0 R14: ffffffffffffffff R15: 00007fff7d67e380
 </TASK>

Allocated by task 5850:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4341 [inline]
 __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:909 [inline]
 sk_prot_alloc+0xe7/0x220 net/core/sock.c:2198
 sk_alloc+0x3a/0x370 net/core/sock.c:2254
 bt_sock_alloc+0x3b/0x310 net/bluetooth/af_bluetooth.c:148
 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1891 [inline]
 l2cap_sock_new_connection_cb+0xe2/0x2b0 net/bluetooth/l2cap_sock.c:1482
 l2cap_connect_cfm+0x377/0x1040 net/bluetooth/l2cap_core.c:7262
 hci_connect_cfm include/net/bluetooth/hci_core.h:2052 [inline]
 hci_remote_features_evt+0x581/0x8e0 net/bluetooth/hci_event.c:3736
 hci_event_func net/bluetooth/hci_event.c:7486 [inline]
 hci_event_packet+0x7fb/0x1270 net/bluetooth/hci_event.c:7538
 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4020
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 11153:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2398 [inline]
 slab_free mm/slub.c:4656 [inline]
 kfree+0x193/0x440 mm/slub.c:4855
 sk_prot_free net/core/sock.c:2237 [inline]
 __sk_destruct+0x4e1/0x660 net/core/sock.c:2332
 bt_accept_dequeue+0x3ce/0x590 net/bluetooth/af_bluetooth.c:305
 l2cap_sock_cleanup_listen+0x2f/0x3e0 net/bluetooth/l2cap_sock.c:1451
 l2cap_sock_release+0x5d/0x1d0 net/bluetooth/l2cap_sock.c:1425
 __sock_release net/socket.c:647 [inline]
 sock_close+0xc0/0x240 net/socket.c:1391
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807fa70000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 452 bytes inside of
 freed 2048-byte region [ffff88807fa70000, ffff88807fa70800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7fa70
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a042000 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a042000 dead000000000100 dead000000000122
head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001fe9c01 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 5878, tgid 5878 (kworker/0:3), ts 93679147739, free_ts 93611872559
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2468 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2632
 new_slab mm/slub.c:2686 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3872
 __slab_alloc mm/slub.c:3962 [inline]
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 __do_kmalloc_node mm/slub.c:4340 [inline]
 __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4360
 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:599
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1340 [inline]
 mld_newpack+0x13c/0xc40 net/ipv6/mcast.c:1788
 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1899
 add_grec+0x13b2/0x1670 net/ipv6/mcast.c:2037
 mld_send_cr net/ipv6/mcast.c:2163 [inline]
 mld_ifc_work+0x6e6/0xde0 net/ipv6/mcast.c:2702
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
page last free pid 1207 tgid 1207 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0xb0e/0xcd0 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2730 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3199
 put_cpu_partial+0x17c/0x250 mm/slub.c:3274
 __slab_free+0x2f7/0x400 mm/slub.c:4526
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/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:4161 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4262
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:658
 alloc_skb include/linux/skbuff.h:1340 [inline]
 mld_newpack+0x13c/0xc40 net/ipv6/mcast.c:1788
 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1899
 add_grec+0x13b2/0x1670 net/ipv6/mcast.c:2037
 mld_send_initial_cr+0x22d/0x4c0 net/ipv6/mcast.c:2282
 mld_dad_work+0x45/0x520 net/ipv6/mcast.c:2308
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400

Memory state around the buggy address:
 ffff88807fa70080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807fa70100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807fa70180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff88807fa70200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807fa70280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================