Bluetooth: hci0: unexpected event 0x2f length: 763 > 260
Bluetooth: Unexpected start frame (len 18)
==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: slab-use-after-free in refcount_read include/linux/refcount.h:136 [inline]
BUG: KASAN: slab-use-after-free in skb_unref include/linux/skbuff.h:1228 [inline]
BUG: KASAN: slab-use-after-free in __sk_skb_reason_drop net/core/skbuff.c:1211 [inline]
BUG: KASAN: slab-use-after-free in sk_skb_reason_drop+0x44/0x3d0 net/core/skbuff.c:1239
Read of size 4 at addr ffff8880249124a4 by task kworker/u9:4/5099

CPU: 1 UID: 0 PID: 5099 Comm: kworker/u9:4 Not tainted 6.10.0-rc7-next-20240709-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: hci0 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
 refcount_read include/linux/refcount.h:136 [inline]
 skb_unref include/linux/skbuff.h:1228 [inline]
 __sk_skb_reason_drop net/core/skbuff.c:1211 [inline]
 sk_skb_reason_drop+0x44/0x3d0 net/core/skbuff.c:1239
 kfree_skb_reason include/linux/skbuff.h:1260 [inline]
 kfree_skb include/linux/skbuff.h:1269 [inline]
 l2cap_recv_reset net/bluetooth/l2cap_core.c:7472 [inline]
 l2cap_recv_acldata+0x335/0x1560 net/bluetooth/l2cap_core.c:7496
 hci_acldata_packet net/bluetooth/hci_core.c:3797 [inline]
 hci_rx_work+0x50f/0xca0 net/bluetooth/hci_core.c:4034
 process_one_work kernel/workqueue.c:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 5099:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:4002 [inline]
 slab_alloc_node mm/slub.c:4051 [inline]
 kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4094
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:664
 alloc_skb include/linux/skbuff.h:1320 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:493 [inline]
 l2cap_recv_frag net/bluetooth/l2cap_core.c:7419 [inline]
 l2cap_recv_acldata+0x7f8/0x1560 net/bluetooth/l2cap_core.c:7527
 hci_acldata_packet net/bluetooth/hci_core.c:3797 [inline]
 hci_rx_work+0x50f/0xca0 net/bluetooth/hci_core.c:4034
 process_one_work kernel/workqueue.c:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 5103:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2258 [inline]
 slab_free mm/slub.c:4487 [inline]
 kmem_cache_free+0x145/0x350 mm/slub.c:4562
 kfree_skb_reason include/linux/skbuff.h:1260 [inline]
 kfree_skb include/linux/skbuff.h:1269 [inline]
 l2cap_conn_del+0x8e/0x680 net/bluetooth/l2cap_core.c:1760
 l2cap_connect_cfm+0x11f/0x1220 net/bluetooth/l2cap_core.c:7240
 hci_connect_cfm include/net/bluetooth/hci_core.h:1965 [inline]
 hci_conn_failed+0x1f6/0x340 net/bluetooth/hci_conn.c:1265
 hci_abort_conn_sync+0x583/0xde0 net/bluetooth/hci_sync.c:5510
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:328
 process_one_work kernel/workqueue.c:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

The buggy address belongs to the object at ffff8880249123c0
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 228 bytes inside of
 freed 240-byte region [ffff8880249123c0, ffff8880249124b0)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x24912
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000000 ffff888018ee4780 dead000000000122 0000000000000000
raw: 0000000000000000 00000000000c000c 00000001fdffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 10067, tgid 10067 (syz-executor), ts 275527187691, free_ts 275338874113
 create_dummy_stack mm/page_owner.c:94 [inline]
 register_dummy_stack+0x8a/0xe0 mm/page_owner.c:100
 init_page_owner+0x3e/0x970 mm/page_owner.c:118
 invoke_init_callbacks mm/page_ext.c:148 [inline]
 page_ext_init+0x732/0x790 mm/page_ext.c:507
 mm_core_init+0x4c/0x60 mm/mm_init.c:2680
page last free pid 10067 tgid 10067 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1094 [inline]
 free_unref_page+0xd22/0xea0 mm/page_alloc.c:2644
 discard_slab mm/slub.c:2589 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3057
 put_cpu_partial+0x17c/0x250 mm/slub.c:3132
 __slab_free+0x2ea/0x3d0 mm/slub.c:4357
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:4002 [inline]
 slab_alloc_node mm/slub.c:4051 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4058
 getname_flags+0xb7/0x540 fs/namei.c:139
 __se_sys_unlinkat fs/namei.c:4479 [inline]
 __x64_sys_unlinkat+0xb1/0xf0 fs/namei.c:4479
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888024912380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
 ffff888024912400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888024912480: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff888024912500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888024912580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
==================================================================