================================================================== BUG: KASAN: use-after-free in hci_conn_unlink net/bluetooth/hci_conn.c:1084 [inline] BUG: KASAN: use-after-free in hci_conn_hash_flush+0x1b0/0x270 net/bluetooth/hci_conn.c:2509 Write of size 8 at addr ffff0000d0b44ac8 by task syz.7.165/5656 CPU: 0 PID: 5656 Comm: syz.7.165 Not tainted 6.1.141-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x88/0x220 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:427 kasan_report+0xa8/0x100 mm/kasan/report.c:531 __asan_report_store8_noabort+0x2c/0x38 mm/kasan/report_generic.c:356 hci_conn_unlink net/bluetooth/hci_conn.c:1084 [inline] hci_conn_hash_flush+0x1b0/0x270 net/bluetooth/hci_conn.c:2509 hci_dev_close_sync+0x7d8/0xf18 net/bluetooth/hci_sync.c:5178 hci_dev_do_close net/bluetooth/hci_core.c:510 [inline] hci_unregister_dev+0x1f8/0x4b4 net/bluetooth/hci_core.c:2707 vhci_release+0x7c/0xcc drivers/bluetooth/hci_vhci.c:573 __fput+0x1bc/0x7c0 fs/file_table.c:320 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x1ec/0x270 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x544/0x19a8 kernel/exit.c:871 do_group_exit+0x194/0x22c kernel/exit.c:1021 get_signal+0x11d0/0x1310 kernel/signal.c:2871 do_signal arch/arm64/kernel/signal.c:1081 [inline] do_notify_resume+0x340/0x2b0c arch/arm64/kernel/signal.c:1134 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Allocated by task 4634: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_alloc_info+0x28/0x34 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace+0x7c/0x94 mm/slab_common.c:1031 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] hci_conn_add+0xc4/0x1078 net/bluetooth/hci_conn.c:989 hci_connect_sco+0x94/0x378 net/bluetooth/hci_conn.c:1629 sco_connect net/bluetooth/sco.c:280 [inline] sco_sock_connect+0x22c/0x7bc net/bluetooth/sco.c:616 __sys_connect_file net/socket.c:2011 [inline] __sys_connect+0x264/0x28c net/socket.c:2028 __do_sys_connect net/socket.c:2038 [inline] __se_sys_connect net/socket.c:2035 [inline] __arm64_sys_connect+0x7c/0x94 net/socket.c:2035 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Freed by task 5656: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_free_info+0x3c/0x60 mm/kasan/generic.c:516 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x16c/0x1ec mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xc0/0x224 mm/slub.c:3674 kfree+0xd0/0x1ac mm/slab_common.c:988 bt_link_release+0x20/0x30 net/bluetooth/hci_sysfs.c:14 device_release+0x8c/0x1ac drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:681 [inline] kobject_release lib/kobject.c:712 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x2b0/0x438 lib/kobject.c:729 put_device+0x28/0x40 drivers/base/core.c:3805 hci_conn_del_sysfs+0x78/0x150 net/bluetooth/hci_sysfs.c:60 hci_conn_cleanup+0x4e0/0x698 net/bluetooth/hci_conn.c:172 hci_conn_del+0x3cc/0x5a8 net/bluetooth/hci_conn.c:1151 hci_conn_hash_flush+0x1d8/0x270 net/bluetooth/hci_conn.c:2510 hci_dev_close_sync+0x7d8/0xf18 net/bluetooth/hci_sync.c:5178 hci_dev_do_close net/bluetooth/hci_core.c:510 [inline] hci_unregister_dev+0x1f8/0x4b4 net/bluetooth/hci_core.c:2707 vhci_release+0x7c/0xcc drivers/bluetooth/hci_vhci.c:573 __fput+0x1bc/0x7c0 fs/file_table.c:320 ____fput+0x20/0x30 fs/file_table.c:348 task_work_run+0x1ec/0x270 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x544/0x19a8 kernel/exit.c:871 do_group_exit+0x194/0x22c kernel/exit.c:1021 get_signal+0x11d0/0x1310 kernel/signal.c:2871 do_signal arch/arm64/kernel/signal.c:1081 [inline] do_notify_resume+0x340/0x2b0c arch/arm64/kernel/signal.c:1134 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 The buggy address belongs to the object at ffff0000d0b44000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2760 bytes inside of 4096-byte region [ffff0000d0b44000, ffff0000d0b45000) The buggy address belongs to the physical page: page:000000002dfd1ecb refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x110b40 head:000000002dfd1ecb order:3 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc00037ce200 dead000000000002 ffff0000c0002a80 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d0b44980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000d0b44a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000d0b44a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000d0b44b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000d0b44b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ocfs2: Unmounting device (7,7) on (node local)