================================================================== BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:172 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:664 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x830/0x1010 kernel/locking/mutex.c:730 Read of size 8 at addr ffff88802a469b20 by task kworker/0:8/10438 CPU: 0 UID: 0 PID: 10438 Comm: kworker/0:8 Not tainted 6.14.0-rc3-syzkaller-00743-g287044abff82 #0 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:172 [inline] __mutex_lock_common kernel/locking/mutex.c:664 [inline] __mutex_lock+0x830/0x1010 kernel/locking/mutex.c:730 l2cap_chan_timeout+0x63/0x360 net/bluetooth/l2cap_core.c:417 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 12094: 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:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4325 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] l2cap_conn_add+0xa9/0x8e0 net/bluetooth/l2cap_core.c:6820 l2cap_chan_connect+0x61e/0xeb0 net/bluetooth/l2cap_core.c:7011 l2cap_sock_connect+0x620/0x950 net/bluetooth/l2cap_sock.c:256 kernel_connect+0x119/0x180 net/socket.c:3615 rfcomm_session_create net/bluetooth/rfcomm/core.c:811 [inline] __rfcomm_dlc_open net/bluetooth/rfcomm/core.c:388 [inline] rfcomm_dlc_open+0xadc/0x10d0 net/bluetooth/rfcomm/core.c:431 rfcomm_sock_connect+0x305/0x610 net/bluetooth/rfcomm/sock.c:409 __sys_connect_file net/socket.c:2045 [inline] __sys_connect+0x288/0x2d0 net/socket.c:2064 __do_sys_connect net/socket.c:2070 [inline] __se_sys_connect net/socket.c:2067 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2067 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 Freed by task 11977: 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:2353 [inline] slab_free mm/slub.c:4609 [inline] kfree+0x196/0x430 mm/slub.c:4757 hci_disconn_cfm include/net/bluetooth/hci_core.h:2069 [inline] hci_conn_hash_flush+0x1be/0x350 net/bluetooth/hci_conn.c:2698 hci_dev_close_sync+0xa8b/0x1260 net/bluetooth/hci_sync.c:5197 hci_dev_do_close net/bluetooth/hci_core.c:482 [inline] hci_unregister_dev+0x20b/0x510 net/bluetooth/hci_core.c:2677 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:664 __fput+0x3e9/0x9f0 fs/file_table.c:464 task_work_run+0x24f/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2a/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232 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 The buggy address belongs to the object at ffff88802a469800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 800 bytes inside of freed 1024-byte region [ffff88802a469800, ffff88802a469c00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a468 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 ffff88801b041dc0 ffffea0001671800 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b041dc0 ffffea0001671800 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000a91a01 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 5647, tgid 5647 (dhcpcd), ts 55458608870, free_ts 55456766781 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2587 new_slab mm/slub.c:2640 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826 __slab_alloc+0x58/0xa0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_node_noprof+0x2ee/0x4d0 mm/slub.c:4300 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:662 bpf_jit_binary_pack_alloc+0x167/0x340 kernel/bpf/core.c:1159 bpf_int_jit_compile+0x908/0x1910 arch/x86/net/bpf_jit_comp.c:3555 bpf_prog_select_runtime+0x4a3/0x810 kernel/bpf/core.c:2428 bpf_migrate_filter net/core/filter.c:1307 [inline] bpf_prepare_filter+0x1288/0x1580 net/core/filter.c:1355 bpf_prog_create_from_user+0x2af/0x3e0 net/core/filter.c:1449 seccomp_prepare_filter kernel/seccomp.c:693 [inline] seccomp_prepare_user_filter kernel/seccomp.c:730 [inline] seccomp_set_mode_filter kernel/seccomp.c:1965 [inline] do_seccomp+0x90d/0xf90 kernel/seccomp.c:2085 __do_sys_prctl kernel/sys.c:2551 [inline] __se_sys_prctl+0x387/0x40f0 kernel/sys.c:2469 page last free pid 5502 tgid 5502 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 __slab_free+0x2c2/0x380 mm/slub.c:4520 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:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_node_noprof+0x23c/0x4d0 mm/slub.c:4300 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:662 proc_sys_call_handler+0x45f/0x920 fs/proc/proc_sysctl.c:584 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x975/0xb40 fs/read_write.c:565 ksys_read+0x18f/0x2b0 fs/read_write.c:708 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: ffff88802a469a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802a469a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802a469b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802a469b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802a469c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================