=========================
WARNING: held lock freed!
6.15.0-syzkaller-07802-g558428921edd #0 Not tainted
-------------------------
syz.4.906/9131 is freeing memory ffff88807f68c000-ffff88807f68c7ff, with a lock still held there!
ffff88807f68c258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline]
ffff88807f68c258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: bt_accept_dequeue+0xfc/0x590 net/bluetooth/af_bluetooth.c:279
2 locks held by syz.4.906/9131:
#0: ffff888061cf2c08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#0: ffff888061cf2c08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
#0: ffff888061cf2c08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391
#1: ffff88807f68c258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1667 [inline]
#1: ffff88807f68c258 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: bt_accept_dequeue+0xfc/0x590 net/bluetooth/af_bluetooth.c:279
stack backtrace:
CPU: 1 UID: 0 PID: 9131 Comm: syz.4.906 Not tainted 6.15.0-syzkaller-07802-g558428921edd #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_freed_lock_bug kernel/locking/lockdep.c:6688 [inline]
debug_check_no_locks_freed+0x18b/0x1c0 kernel/locking/lockdep.c:6723
slab_free_hook mm/slub.c:2308 [inline]
slab_free mm/slub.c:4642 [inline]
kfree+0xfd/0x440 mm/slub.c:4841
sk_prot_free net/core/sock.c:2286 [inline]
__sk_destruct+0x4e1/0x660 net/core/sock.c:2381
bt_accept_dequeue+0x3ce/0x590 net/bluetooth/af_bluetooth.c:308
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+0xc3/0x240 net/socket.c:1391
__fput+0x44c/0xa70 fs/file_table.c:465
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x8d1/0x2550 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1108
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f8bf8e969
Code: Unable to access opcode bytes at 0x7f5f8bf8e93f.
RSP: 002b:00007f5f8cddb038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: fffffffffffffe00 RBX: 00007f5f8c1b5fa0 RCX: 00007f5f8bf8e969
RDX: 0000000000000001 RSI: 0000200000002e00 RDI: 000000000000000b
RBP: 00007f5f8c010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 00007fb14727dcaa R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5f8c1b5fa0 R15: 00007ffeda4fff48
==================================================================
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 ffff88807f68c1c4 by task syz.4.906/9131
CPU: 0 UID: 0 PID: 9131 Comm: syz.4.906 Not tainted 6.15.0-syzkaller-07802-g558428921edd #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xd2/0x2b0 mm/kasan/report.c:521
kasan_report+0x118/0x150 mm/kasan/report.c:634
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:3765
bt_accept_dequeue+0x512/0x590 net/bluetooth/af_bluetooth.c:312
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+0xc3/0x240 net/socket.c:1391
__fput+0x44c/0xa70 fs/file_table.c:465
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x8d1/0x2550 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1108
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f8bf8e969
Code: Unable to access opcode bytes at 0x7f5f8bf8e93f.
RSP: 002b:00007f5f8cddb038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: fffffffffffffe00 RBX: 00007f5f8c1b5fa0 RCX: 00007f5f8bf8e969
RDX: 0000000000000001 RSI: 0000200000002e00 RDI: 000000000000000b
RBP: 00007f5f8c010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 00007fb14727dcaa R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5f8c1b5fa0 R15: 00007ffeda4fff48
Allocated by task 5847:
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:4327 [inline]
__kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4339
kmalloc_noprof include/linux/slab.h:909 [inline]
sk_prot_alloc+0xe7/0x220 net/core/sock.c:2247
sk_alloc+0x3a/0x370 net/core/sock.c:2303
bt_sock_alloc+0x3b/0x310 net/bluetooth/af_bluetooth.c:151
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+0x37a/0x1040 net/bluetooth/l2cap_core.c:7264
hci_connect_cfm include/net/bluetooth/hci_core.h:2050 [inline]
hci_remote_features_evt+0x581/0x8e0 net/bluetooth/hci_event.c:3747
hci_event_func net/bluetooth/hci_event.c:7511 [inline]
hci_event_packet+0x7e3/0x1200 net/bluetooth/hci_event.c:7565
hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4036
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Freed by task 9131:
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:2380 [inline]
slab_free mm/slub.c:4642 [inline]
kfree+0x18e/0x440 mm/slub.c:4841
sk_prot_free net/core/sock.c:2286 [inline]
__sk_destruct+0x4e1/0x660 net/core/sock.c:2381
bt_accept_dequeue+0x3ce/0x590 net/bluetooth/af_bluetooth.c:308
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+0xc3/0x240 net/socket.c:1391
__fput+0x44c/0xa70 fs/file_table.c:465
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x8d1/0x2550 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1108
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807f68c000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 452 bytes inside of
freed 2048-byte region [ffff88807f68c000, ffff88807f68c800)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f688
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 ffff88801a442000 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a442000 dead000000000100 dead000000000122
head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001fda201 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 5189, tgid 5189 (klogd), ts 136744823310, free_ts 136725759181
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1710
prep_new_page mm/page_alloc.c:1718 [inline]
get_page_from_freelist+0x21e0/0x22c0 mm/page_alloc.c:3680
__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:2450 [inline]
allocate_slab+0x8a/0x3b0 mm/slub.c:2618
new_slab mm/slub.c:2672 [inline]
___slab_alloc+0xbfc/0x1480 mm/slub.c:3858
__slab_alloc mm/slub.c:3948 [inline]
__slab_alloc_node mm/slub.c:4023 [inline]
slab_alloc_node mm/slub.c:4184 [inline]
__kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4353
kmalloc_noprof include/linux/slab.h:905 [inline]
syslog_print+0xd2/0x590 kernel/printk/printk.c:1607
do_syslog+0x544/0x760 kernel/printk/printk.c:1785
__do_sys_syslog kernel/printk/printk.c:1877 [inline]
__se_sys_syslog kernel/printk/printk.c:1875 [inline]
__x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1875
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 8416 tgid 8414 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1254 [inline]
__free_frozen_pages+0xc6e/0xe50 mm/page_alloc.c:2717
__folio_put+0x21b/0x2c0 mm/swap.c:112
folio_put include/linux/mm.h:1580 [inline]
put_page include/linux/mm.h:1649 [inline]
do_exit+0x1a3a/0x2550 kernel/exit.c:998
do_group_exit+0x21c/0x2d0 kernel/exit.c:1108
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807f68c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807f68c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807f68c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807f68c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807f68c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================