==================================================================
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0x598/0xe24 net/bluetooth/l2cap_core.c:7278
Read of size 8 at addr ffff0000ed632480 by task kworker/u9:0/54

CPU: 1 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.12.0-rc6-syzkaller-g563047e691f2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: hci4 hci_rx_work
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:484 (C)
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x198/0x538 mm/kasan/report.c:488
 kasan_report+0xd8/0x138 mm/kasan/report.c:601
 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381
 l2cap_connect_cfm+0x598/0xe24 net/bluetooth/l2cap_core.c:7278
 hci_connect_cfm+0xa0/0x13c include/net/bluetooth/hci_core.h:1960
 le_conn_complete_evt+0xa1c/0xf0c net/bluetooth/hci_event.c:5758
 hci_le_conn_complete_evt+0x114/0x404 net/bluetooth/hci_event.c:5784
 hci_le_meta_evt+0x2a4/0x478 net/bluetooth/hci_event.c:7132
 hci_event_func net/bluetooth/hci_event.c:7440 [inline]
 hci_event_packet+0x890/0x106c net/bluetooth/hci_event.c:7495
 hci_rx_work+0x324/0xaf0 net/bluetooth/hci_core.c:4031
 process_one_work+0x7bc/0x1600 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x97c/0xeec kernel/workqueue.c:3391
 kthread+0x288/0x310 kernel/kthread.c:389
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862

Allocated by task 54:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:68
 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:257 [inline]
 __kmalloc_cache_noprof+0x244/0x378 mm/slub.c:4295
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 l2cap_chan_create+0x58/0x6a0 net/bluetooth/l2cap_core.c:449
 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1886 [inline]
 l2cap_sock_new_connection_cb+0x164/0x284 net/bluetooth/l2cap_sock.c:1468
 l2cap_connect_cfm+0x2fc/0xe24 net/bluetooth/l2cap_core.c:7261
 hci_connect_cfm+0xa0/0x13c include/net/bluetooth/hci_core.h:1960
 le_conn_complete_evt+0xa1c/0xf0c net/bluetooth/hci_event.c:5758
 hci_le_conn_complete_evt+0x114/0x404 net/bluetooth/hci_event.c:5784
 hci_le_meta_evt+0x2a4/0x478 net/bluetooth/hci_event.c:7132
 hci_event_func net/bluetooth/hci_event.c:7440 [inline]
 hci_event_packet+0x890/0x106c net/bluetooth/hci_event.c:7495
 hci_rx_work+0x324/0xaf0 net/bluetooth/hci_core.c:4031
 process_one_work+0x7bc/0x1600 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x97c/0xeec kernel/workqueue.c:3391
 kthread+0x288/0x310 kernel/kthread.c:389
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862

Freed by task 7401:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:68
 kasan_save_free_info+0x54/0x6c mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x64/0x8c mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:2342 [inline]
 slab_free mm/slub.c:4579 [inline]
 kfree+0x184/0x47c mm/slub.c:4727
 l2cap_chan_destroy net/bluetooth/l2cap_core.c:495 [inline]
 kref_put include/linux/kref.h:65 [inline]
 l2cap_chan_put+0x174/0x254 net/bluetooth/l2cap_core.c:519
 l2cap_sock_cleanup_listen+0x108/0x290 net/bluetooth/l2cap_sock.c:1451
 l2cap_sock_release+0x5c/0x1b4 net/bluetooth/l2cap_sock.c:1411
 __sock_release net/socket.c:658 [inline]
 sock_close+0xa4/0x1e8 net/socket.c:1426
 __fput+0x1bc/0x75c fs/file_table.c:431
 ____fput+0x20/0x30 fs/file_table.c:459
 task_work_run+0x230/0x2e0 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 do_notify_resume+0x178/0x1f4 arch/arm64/kernel/entry-common.c:151
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline]
 el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:745
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

The buggy address belongs to the object at ffff0000ed632000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
 freed 2048-byte region [ffff0000ed632000, ffff0000ed632800)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000ed630000 pfn:0x12d630
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 05ffc00000000040 ffff0000c0002000 0000000000000000 dead000000000001
raw: ffff0000ed630000 0000000080080005 00000001f5000000 0000000000000000
head: 05ffc00000000040 ffff0000c0002000 0000000000000000 dead000000000001
head: ffff0000ed630000 0000000080080005 00000001f5000000 0000000000000000
head: 05ffc00000000003 fffffdffc3b58c01 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000ed632380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000ed632400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000ed632480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff0000ed632500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000ed632580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Unable to handle kernel paging request at virtual address fbd51fffffffff91
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
Mem abort info:
  ESR = 0x0000000096000004
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x04: level 0 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[fbd51fffffffff91] address between user and kernel address ranges
Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 UID: 0 PID: 54 Comm: kworker/u9:0 Tainted: G    B              6.12.0-rc6-syzkaller-g563047e691f2 #0
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: hci4 hci_rx_work
pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
pc : atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
pc : l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
pc : l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
pc : l2cap_connect_cfm+0x534/0xe24 net/bluetooth/l2cap_core.c:7278
lr : instrument_atomic_read include/linux/instrumented.h:68 [inline]
lr : atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
lr : l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline]
lr : l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline]
lr : l2cap_connect_cfm+0x530/0xe24 net/bluetooth/l2cap_core.c:7278
sp : ffff800098ff7560
x29: ffff800098ff7600 x28: ffff0000ed632000 x27: 1fffe0001a2a1203
x26: dfff800000000000 x25: ffff0000ed6324b0 x24: ffff0000d150901a
x23: dead000000000100 x22: ffff0000d15092c0 x21: 1fffe0001d531007
x20: ffff0000ea98803b x19: deacfffffffffc8c x18: 1fffe000366cb476
x17: ffff80008f80d000 x16: ffff800080ac6e64 x15: 0000000000000001
x14: 1ffff000125a22e8 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000100000
 x10: fffffffffffffff8 x9 : ffff80009739b3a0
x8 : 1bd59fffffffff91 x7 : 1fffe000366cb477 x6 : ffff8000802c3dfc
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80008a6876a0
x2 : 0000000000000000 x1 : 0000000000000004 x0 : 0000000000000001
Call trace:
 raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline] (P)
 atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline] (P)
 l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline] (P)
 l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline] (P)
 l2cap_connect_cfm+0x534/0xe24 net/bluetooth/l2cap_core.c:7278 (P)
 instrument_atomic_read include/linux/instrumented.h:68 [inline] (L)
 atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] (L)
 l2cap_chan_lock include/net/bluetooth/l2cap.h:827 [inline] (L)
 l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline] (L)
 l2cap_connect_cfm+0x530/0xe24 net/bluetooth/l2cap_core.c:7278 (L)
 hci_connect_cfm+0xa0/0x13c include/net/bluetooth/hci_core.h:1960
 le_conn_complete_evt+0xa1c/0xf0c net/bluetooth/hci_event.c:5758
 hci_le_conn_complete_evt+0x114/0x404 net/bluetooth/hci_event.c:5784
 hci_le_meta_evt+0x2a4/0x478 net/bluetooth/hci_event.c:7132
 hci_event_func net/bluetooth/hci_event.c:7440 [inline]
 hci_event_packet+0x890/0x106c net/bluetooth/hci_event.c:7495
 hci_rx_work+0x324/0xaf0 net/bluetooth/hci_core.c:4031
 process_one_work+0x7bc/0x1600 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x97c/0xeec kernel/workqueue.c:3391
 kthread+0x288/0x310 kernel/kthread.c:389
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862
Code: 52800081 aa1303e0 97628f13 d343fe68 (38fa6908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	52800081 	mov	w1, #0x4                   	// #4
   4:	aa1303e0 	mov	x0, x19
   8:	97628f13 	bl	0xfffffffffd8a3c54
   c:	d343fe68 	lsr	x8, x19, #3
* 10:	38fa6908 	ldrsb	w8, [x8, x26] <-- trapping instruction