kobject: kobject_add_internal failed for hci5:201 with -EEXIST, don't try to register things with the same name in the same directory. Bluetooth: hci5: failed to register connection device ================================================================== BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0x70a/0x1220 net/bluetooth/l2cap_core.c:7278 Read of size 8 at addr ffff888054025480 by task kworker/u9:0/54 CPU: 0 UID: 0 PID: 54 Comm: kworker/u9:0 Not tainted 6.12.0-rc5-syzkaller-00322-gb9021de3ec2f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci5 hci_rx_work Call Trace: __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 l2cap_connect_cfm+0x70a/0x1220 net/bluetooth/l2cap_core.c:7278 hci_connect_cfm+0xa4/0x150 include/net/bluetooth/hci_core.h:1960 le_conn_complete_evt+0xd3e/0x12e0 net/bluetooth/hci_event.c:5758 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5784 hci_event_func net/bluetooth/hci_event.c:7440 [inline] hci_event_packet+0xa57/0x1540 net/bluetooth/hci_event.c:7495 hci_rx_work+0x3fe/0xd80 net/bluetooth/hci_core.c:4031 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 54: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4295 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] l2cap_chan_create+0x50/0x760 net/bluetooth/l2cap_core.c:449 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1886 [inline] l2cap_sock_new_connection_cb+0x181/0x2b0 net/bluetooth/l2cap_sock.c:1468 l2cap_connect_cfm+0x379/0x1220 net/bluetooth/l2cap_core.c:7261 hci_connect_cfm+0xa4/0x150 include/net/bluetooth/hci_core.h:1960 le_conn_complete_evt+0xd3e/0x12e0 net/bluetooth/hci_event.c:5758 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5784 hci_event_func net/bluetooth/hci_event.c:7440 [inline] hci_event_packet+0xa57/0x1540 net/bluetooth/hci_event.c:7495 hci_rx_work+0x3fe/0xd80 net/bluetooth/hci_core.c:4031 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 10904: 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 mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 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+0x1a0/0x440 mm/slub.c:4727 l2cap_sock_cleanup_listen+0xed/0x3c0 net/bluetooth/l2cap_sock.c:1451 l2cap_sock_release+0x5d/0x1d0 net/bluetooth/l2cap_sock.c:1411 __sock_release net/socket.c:658 [inline] sock_close+0xbe/0x240 net/socket.c:1426 __fput+0x241/0x880 fs/file_table.c:431 task_work_run+0x251/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888054025000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1152 bytes inside of freed 2048-byte region [ffff888054025000, ffff888054025800) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x54020 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 ffff88801ac42000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080080008 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac42000 dead000000000122 0000000000000000 head: 0000000000000000 0000000080080008 00000001f5000000 0000000000000000 head: 00fff00000000003 ffffea0001500801 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 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 79, tgid 79 (kworker/u8:4), ts 251119542684, free_ts 250818659881 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x303f/0x3190 mm/page_alloc.c:3457 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x120 mm/slub.c:2412 allocate_slab+0x5a/0x2f0 mm/slub.c:2578 new_slab mm/slub.c:2631 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818 __slab_alloc+0x58/0xa0 mm/slub.c:3908 __slab_alloc_node mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4122 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_node_track_caller_noprof+0x281/0x440 mm/slub.c:4283 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1322 [inline] nlmsg_new include/net/netlink.h:1015 [inline] rtmsg_ifinfo_build_skb+0x84/0x260 net/core/rtnetlink.c:4099 unregister_netdevice_many_notify+0xf71/0x1da0 net/core/dev.c:11411 cleanup_net+0x75d/0xcc0 net/core/net_namespace.c:621 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 page last free pid 10524 tgid 10524 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 __slab_free+0x31b/0x3d0 mm/slub.c:4490 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/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:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141 getname_flags+0xb7/0x540 fs/namei.c:139 user_path_at+0x24/0x60 fs/namei.c:3015 ksys_umount fs/namespace.c:2033 [inline] __do_sys_umount fs/namespace.c:2041 [inline] __se_sys_umount fs/namespace.c:2039 [inline] __x64_sys_umount+0xf1/0x170 fs/namespace.c:2039 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: ffff888054025380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888054025400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888054025480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888054025500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888054025580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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