=========================[ 1098.260647][T16189] ==================================================================
BUG: KASAN: slab-use-after-free in l2cap_sock_ready_cb+0xe3/0x180 net/bluetooth/l2cap_sock.c:1788
Read of size 8 at addr ffff8880405bc200 by task kworker/u9:2/16189

CPU: 0 UID: 0 PID: 16189 Comm: kworker/u9:2 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: hci5 hci_rx_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 l2cap_sock_ready_cb+0xe3/0x180 net/bluetooth/l2cap_sock.c:1788
 l2cap_le_start+0x257/0x1910 net/bluetooth/l2cap_core.c:1420
 l2cap_conn_ready net/bluetooth/l2cap_core.c:1673 [inline]
 l2cap_connect_cfm+0x950/0x1620 net/bluetooth/l2cap_core.c:7575
 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2137
 le_conn_complete_evt+0x1034/0x1580 net/bluetooth/hci_event.c:5872
 hci_le_conn_complete_evt+0x187/0x470 net/bluetooth/hci_event.c:5898
 hci_event_func net/bluetooth/hci_event.c:7800 [inline]
 hci_event_packet+0x67a/0xf10 net/bluetooth/hci_event.c:7854
 hci_rx_work+0x3ee/0x1020 net/bluetooth/hci_core.c:4042
 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379
 process_scheduled_works kernel/workqueue.c:3462 [inline]
 worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 24197:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5339 [inline]
 __kmalloc_noprof+0x415/0x790 mm/slub.c:5364
 _kmalloc_noprof include/linux/slab.h:973 [inline]
 sk_prot_alloc+0xe7/0x210 net/core/sock.c:2252
 sk_alloc+0x3a/0x390 net/core/sock.c:2308
 bt_sock_alloc+0x3b/0x340 net/bluetooth/af_bluetooth.c:148
 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1981 [inline]
 l2cap_sock_create+0x15a/0x300 net/bluetooth/l2cap_sock.c:2019
 bt_sock_create+0x163/0x240 net/bluetooth/af_bluetooth.c:132
 __sock_create+0x4e8/0x960 net/socket.c:1691
 sock_create net/socket.c:1749 [inline]
 __sys_socket_create net/socket.c:1786 [inline]
 __sys_socket+0xd9/0x320 net/socket.c:1833
 __do_sys_socket net/socket.c:1847 [inline]
 __se_sys_socket net/socket.c:1845 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1845
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 24196:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2706 [inline]
 slab_free mm/slub.c:6380 [inline]
 kfree+0x1c5/0x6c0 mm/slub.c:6695
 sk_prot_free net/core/sock.c:2291 [inline]
 __sk_destruct+0x754/0x9e0 net/core/sock.c:2391
 l2cap_sock_release+0x1b3/0x250 net/bluetooth/l2cap_sock.c:1493
 __sock_release+0xa0/0x1f0 net/socket.c:739
 sock_close+0x1c/0x30 net/socket.c:1541
 __fput+0x42a/0xa80 fs/file_table.c:512
 task_work_run+0x1d9/0x270 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+0x1fa/0x730 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:316 [inline]
 do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880405bc000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 512 bytes inside of
 freed 4096-byte region [ffff8880405bc000, ffff8880405bd000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x405b8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813fe3b140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88813fe3b140 dead000000000100 dead000000000122
head: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000
head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 4957, tgid 4957 (udevd), ts 45246630662
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1870
 prep_new_page mm/page_alloc.c:1878 [inline]
 get_page_from_freelist+0x264c/0x26c0 mm/page_alloc.c:3954
 __alloc_frozen_pages_noprof+0x222/0x5b0 mm/page_alloc.c:5393
 alloc_slab_page mm/slub.c:3295 [inline]
 allocate_slab+0x7c/0x5e0 mm/slub.c:3410
 new_slab mm/slub.c:3456 [inline]
 refill_objects+0x2d8/0x350 mm/slub.c:7313
 refill_sheaf mm/slub.c:2833 [inline]
 __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4699
 alloc_from_pcs mm/slub.c:4775 [inline]
 slab_alloc_node mm/slub.c:4909 [inline]
 __kmalloc_cache_noprof+0x467/0x670 mm/slub.c:5482
 _kmalloc_noprof include/linux/slab.h:969 [inline]
 _kzalloc_noprof include/linux/slab.h:1290 [inline]
 uevent_show+0x15c/0x310 drivers/base/core.c:2821
 dev_attr_show+0x58/0xc0 drivers/base/core.c:2487
 sysfs_kf_seq_show+0x331/0x490 fs/sysfs/file.c:65
 seq_read_iter+0x464/0xcb0 fs/seq_file.c:231
 new_sync_read fs/read_write.c:493 [inline]
 vfs_read+0x59e/0xa90 fs/read_write.c:574
 ksys_read+0x156/0x270 fs/read_write.c:716
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8880405bc100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880405bc180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880405bc200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8880405bc280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880405bc300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================