================================================================== BUG: KASAN: slab-use-after-free in cfusbl_device_notify+0x150/0x6a0 net/caif/caif_usb.c:142 Read of size 8 at addr ffff88807d908c50 by task syz.4.983/9262 CPU: 0 UID: 0 PID: 9262 Comm: syz.4.983 Not tainted 6.16.0-rc1-syzkaller-00102-g5466491c9e33 #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 cfusbl_device_notify+0x150/0x6a0 net/caif/caif_usb.c:142 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] register_netdevice+0x121c/0x1ae0 net/core/dev.c:11100 register_netdev+0x40/0x60 net/core/dev.c:11221 bnep_add_connection+0x6bf/0xbf0 net/bluetooth/bnep/core.c:624 do_bnep_sock_ioctl+0x40e/0x640 net/bluetooth/bnep/sock.c:83 sock_do_ioctl+0xd9/0x300 net/socket.c:1190 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 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 RIP: 0033:0x7fa09b78e929 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:00007fa09c692038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa09b9b6080 RCX: 00007fa09b78e929 RDX: 0000200000000540 RSI: 00000000400442c8 RDI: 0000000000000008 RBP: 00007fa09b810b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa09b9b6080 R15: 00007fffb55bb8c8 Allocated by task 5153: 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] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] __hci_conn_add+0x233/0x1b30 net/bluetooth/hci_conn.c:939 hci_conn_request_evt+0x53e/0xb60 net/bluetooth/hci_event.c:3316 hci_event_func net/bluetooth/hci_event.c:7511 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7565 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4044 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 8896: 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:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 device_release+0x9c/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x22b/0x480 lib/kobject.c:737 hci_conn_cleanup net/bluetooth/hci_conn.c:175 [inline] hci_conn_del+0x8ff/0xcb0 net/bluetooth/hci_conn.c:1173 hci_conn_hash_flush+0x191/0x230 net/bluetooth/hci_conn.c:2561 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5250 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_unregister_dev+0x206/0x500 net/bluetooth/hci_core.c:2691 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665 __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+0x6ad/0x22e0 kernel/exit.c:955 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104 __do_sys_exit_group kernel/exit.c:1115 [inline] __se_sys_exit_group kernel/exit.c:1113 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232 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 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 insert_work+0x3d/0x330 kernel/workqueue.c:2183 __queue_work+0xcfc/0xfe0 kernel/workqueue.c:2341 queue_delayed_work_on+0x18b/0x280 kernel/workqueue.c:2561 l2cap_chan_del+0x285/0x5e0 net/bluetooth/l2cap_core.c:671 l2cap_conn_del+0x388/0x680 net/bluetooth/l2cap_core.c:1787 hci_disconn_cfm include/net/bluetooth/hci_core.h:2069 [inline] hci_conn_hash_flush+0x10d/0x230 net/bluetooth/hci_conn.c:2560 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5250 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_unregister_dev+0x206/0x500 net/bluetooth/hci_core.c:2691 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665 __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+0x6ad/0x22e0 kernel/exit.c:955 do_group_exit+0x21c/0x2d0 kernel/exit.c:1104 __do_sys_exit_group kernel/exit.c:1115 [inline] __se_sys_exit_group kernel/exit.c:1113 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232 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 The buggy address belongs to the object at ffff88807d908000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 3152 bytes inside of freed 8192-byte region [ffff88807d908000, ffff88807d90a000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d908 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 ffff88801a442280 ffffea0001a5c000 0000000000000002 raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a442280 ffffea0001a5c000 0000000000000002 head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001f64201 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 0x528c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NORETRY|__GFP_COMP), pid 7867, tgid 7865 (syz.1.581), ts 135644486994, free_ts 133271033376 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kvmalloc_node_noprof+0x429/0x5f0 mm/slub.c:5015 kvmalloc_array_node_noprof include/linux/slab.h:1065 [inline] __ptr_ring_init_queue_alloc_noprof include/linux/ptr_ring.h:471 [inline] ptr_ring_init_noprof include/linux/ptr_ring.h:489 [inline] skb_array_init_noprof include/linux/skb_array.h:182 [inline] pfifo_fast_init+0x238/0x6b0 net/sched/sch_generic.c:867 qdisc_create_dflt+0x13b/0x4e0 net/sched/sch_generic.c:1017 mq_init+0x2dc/0x660 net/sched/sch_mq.c:90 qdisc_create_dflt+0x13b/0x4e0 net/sched/sch_generic.c:1017 attach_default_qdiscs net/sched/sch_generic.c:1199 [inline] dev_activate+0x1ce/0x1150 net/sched/sch_generic.c:1253 __dev_open+0x69c/0x880 net/core/dev.c:1692 __dev_change_flags+0x1ea/0x6d0 net/core/dev.c:9458 netif_change_flags+0x88/0x1a0 net/core/dev.c:9521 dev_change_flags+0x130/0x260 net/core/dev_api.c:68 page last free pid 7720 tgid 7719 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 __folio_put+0x21b/0x2c0 mm/swap.c:112 put_netmem net/core/skbuff.c:7375 [inline] skb_page_unref include/linux/skbuff_ref.h:43 [inline] __skb_frag_unref include/linux/skbuff_ref.h:56 [inline] skb_release_data+0x49a/0x7c0 net/core/skbuff.c:1081 skb_release_all net/core/skbuff.c:1152 [inline] kfree_skb_add_bulk net/core/skbuff.c:1225 [inline] kfree_skb_list_reason+0x25d/0x460 net/core/skbuff.c:1247 skb_release_data+0x61e/0x7c0 net/core/skbuff.c:1085 skb_release_all net/core/skbuff.c:1152 [inline] __kfree_skb net/core/skbuff.c:1166 [inline] sk_skb_reason_drop+0x127/0x170 net/core/skbuff.c:1204 kfree_skb_reason include/linux/skbuff.h:1275 [inline] kfree_skb include/linux/skbuff.h:1284 [inline] kcm_sendmsg+0x389/0x2a70 net/kcm/kcmsock.c:945 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655 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 Memory state around the buggy address: ffff88807d908b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807d908b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807d908c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807d908c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807d908d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================