================================================================== BUG: KASAN: slab-use-after-free in cfusbl_device_notify+0x150/0x6a0 net/caif/caif_usb.c:142 Read of size 8 at addr ffff888028960c50 by task syz.1.2264/13552 CPU: 1 UID: 0 PID: 13552 Comm: syz.1.2264 Not tainted 6.16.0-rc5-syzkaller-00186-ga059ef8e8889 #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+0x12ee/0x1ae0 net/core/dev.c:11163 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+0xfc/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: 0033:0x7f9c4c98e929 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:00007f9c4d8e2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9c4cbb5fa0 RCX: 00007f9c4c98e929 RDX: 0000200000000540 RSI: 00000000400442c8 RDI: 0000000000000008 RBP: 00007f9c4ca10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9c4cbb5fa0 R15: 00007ffeb3f67ec8 Allocated by task 51: 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:3282 hci_event_func net/bluetooth/hci_event.c:7478 [inline] hci_event_packet+0x7e0/0x1200 net/bluetooth/hci_event.c:7532 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4070 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 13552: 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+0x99/0x1c0 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 put_device drivers/base/core.c:3800 [inline] device_add+0x6bb/0xb50 drivers/base/core.c:3745 netdev_register_kobject+0x156/0x2f0 net/core/net-sysfs.c:2336 register_netdevice+0x126c/0x1ae0 net/core/dev.c:11105 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+0xfc/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 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:2070 [inline] hci_conn_hash_flush+0x10d/0x230 net/bluetooth/hci_conn.c:2560 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5294 hci_dev_do_close net/bluetooth/hci_core.c:501 [inline] hci_unregister_dev+0x21a/0x510 net/bluetooth/hci_core.c:2717 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665 __fput+0x449/0xa70 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+0x6b5/0x22e0 kernel/exit.c:964 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 __do_sys_exit_group kernel/exit.c:1116 [inline] __se_sys_exit_group kernel/exit.c:1114 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1114 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 ffff888028960000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 3152 bytes inside of freed 8192-byte region [ffff888028960000, ffff888028962000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28960 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a442280 ffffea0001db9a00 0000000000000003 raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a442280 ffffea0001db9a00 0000000000000003 head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000a25801 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 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 11572, tgid 11571 (syz.0.1666), ts 188162228700, free_ts 188111060484 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] __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4347 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1336 [inline] netlink_dump+0x161/0xe60 net/netlink/af_netlink.c:2286 netlink_recvmsg+0x676/0xa30 net/netlink/af_netlink.c:1978 sock_recvmsg_nosec+0x186/0x1c0 net/socket.c:1017 ____sys_recvmsg+0x3aa/0x460 net/socket.c:2784 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2828 do_recvmmsg+0x307/0x770 net/socket.c:2923 __sys_recvmmsg net/socket.c:2997 [inline] __do_sys_recvmmsg net/socket.c:3020 [inline] __se_sys_recvmmsg net/socket.c:3013 [inline] __x64_sys_recvmmsg+0x190/0x240 net/socket.c:3013 page last free pid 11575 tgid 11575 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 discard_slab mm/slub.c:2717 [inline] __put_partials+0x161/0x1c0 mm/slub.c:3186 put_cpu_partial+0x17c/0x250 mm/slub.c:3261 __slab_free+0x2f7/0x400 mm/slub.c:4513 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] __kmalloc_cache_noprof+0x1be/0x3d0 mm/slub.c:4354 kmalloc_noprof include/linux/slab.h:905 [inline] load_elf_binary+0x1e3c/0x2790 fs/binfmt_elf.c:904 search_binary_handler fs/exec.c:1670 [inline] exec_binprm fs/exec.c:1702 [inline] bprm_execve+0x99c/0x1450 fs/exec.c:1754 kernel_execve+0x8f0/0x9f0 fs/exec.c:1920 call_usermodehelper_exec_async+0x210/0x360 kernel/umh.c:109 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888028960b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028960b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888028960c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888028960c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028960d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================