================================================================== BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:182 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:680 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x81e/0x10c0 kernel/locking/mutex.c:746 Read of size 8 at addr ffff88805eb9bb20 by task kworker/1:0/24 CPU: 1 UID: 0 PID: 24 Comm: kworker/1:0 Not tainted 6.15.0-rc2-syzkaller-00261-gb9a4c74b0ec1 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events l2cap_chan_timeout 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:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 __mutex_waiter_is_first kernel/locking/mutex.c:182 [inline] __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0x81e/0x10c0 kernel/locking/mutex.c:746 l2cap_chan_timeout+0x63/0x360 net/bluetooth/l2cap_core.c:417 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 13675: 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+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x236/0x370 mm/slub.c:4372 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] l2cap_conn_add+0xa9/0x8e0 net/bluetooth/l2cap_core.c:6861 l2cap_chan_connect+0x627/0xea0 net/bluetooth/l2cap_core.c:7052 l2cap_sock_connect+0x622/0x950 net/bluetooth/l2cap_sock.c:256 kernel_connect+0x11b/0x190 net/socket.c:3608 rfcomm_session_create net/bluetooth/rfcomm/core.c:811 [inline] __rfcomm_dlc_open net/bluetooth/rfcomm/core.c:388 [inline] rfcomm_dlc_open+0xad9/0x10d0 net/bluetooth/rfcomm/core.c:431 rfcomm_sock_connect+0x305/0x610 net/bluetooth/rfcomm/sock.c:409 __sys_connect_file net/socket.c:2038 [inline] __sys_connect+0x28c/0x2d0 net/socket.c:2057 __do_sys_connect net/socket.c:2063 [inline] __se_sys_connect net/socket.c:2060 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2060 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 13579: 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:576 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:233 [inline] slab_free_hook mm/slub.c:2398 [inline] slab_free mm/slub.c:4656 [inline] kfree+0x198/0x430 mm/slub.c:4855 hci_disconn_cfm include/net/bluetooth/hci_core.h:2069 [inline] hci_conn_hash_flush+0xff/0x240 net/bluetooth/hci_conn.c:2701 hci_dev_close_sync+0xa8d/0x1260 net/bluetooth/hci_sync.c:5225 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_unregister_dev+0x20b/0x510 net/bluetooth/hci_core.c:2678 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa11/0x27f0 kernel/exit.c:953 do_group_exit+0x207/0x2c0 kernel/exit.c:1102 __do_sys_exit_group kernel/exit.c:1113 [inline] __se_sys_exit_group kernel/exit.c:1111 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111 x64_sys_call+0x26c3/0x26d0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805eb9b800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 800 bytes inside of freed 1024-byte region [ffff88805eb9b800, ffff88805eb9bc00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5eb98 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b041dc0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b041dc0 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea00017ae601 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5866, tgid 5866 (kworker/u8:4), ts 75463826581, free_ts 24364529468 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x360a/0x37a0 mm/page_alloc.c:3700 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4982 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2468 [inline] allocate_slab+0x8f/0x3b0 mm/slub.c:2632 new_slab mm/slub.c:2686 [inline] ___slab_alloc+0xc3b/0x1500 mm/slub.c:3872 __slab_alloc+0x58/0xa0 mm/slub.c:3962 __slab_alloc_node mm/slub.c:4037 [inline] slab_alloc_node mm/slub.c:4198 [inline] __do_kmalloc_node mm/slub.c:4340 [inline] __kmalloc_noprof+0x2ea/0x4d0 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:909 [inline] load_elf_phdrs fs/binfmt_elf.c:532 [inline] load_elf_binary+0x313/0x28a0 fs/binfmt_elf.c:860 search_binary_handler fs/exec.c:1778 [inline] exec_binprm fs/exec.c:1810 [inline] bprm_execve+0x9a9/0x1430 fs/exec.c:1862 kernel_execve+0x92e/0xa50 fs/exec.c:2028 call_usermodehelper_exec_async+0x237/0x380 kernel/umh.c:109 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2725 __free_pages mm/page_alloc.c:5092 [inline] free_contig_range+0x154/0x430 mm/page_alloc.c:6948 destroy_args+0x94/0x4b0 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x555/0x590 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x24a/0x940 init/main.c:1257 do_initcall_level+0x157/0x210 init/main.c:1319 do_initcalls+0x71/0xd0 init/main.c:1335 kernel_init_freeable+0x432/0x5d0 init/main.c:1567 kernel_init+0x1d/0x2b0 init/main.c:1457 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88805eb9ba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805eb9ba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805eb9bb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805eb9bb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805eb9bc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================