================================================================== BUG: KASAN: slab-use-after-free in rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56 Read of size 1 at addr ffff88802c32e7e8 by task syz.2.1633/10532 CPU: 0 UID: 0 PID: 10532 Comm: syz.2.1633 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:574 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire+0x7d/0x350 kernel/locking/lockdep.c:5866 rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56 spin_lock_bh include/linux/spinlock_rt.h:90 [inline] bt_accept_unlink+0x7d/0x2f0 net/bluetooth/af_bluetooth.c:263 l2cap_sock_teardown_cb+0x17e/0x490 net/bluetooth/l2cap_sock.c:1711 l2cap_chan_del+0x98/0x600 net/bluetooth/l2cap_core.c:687 l2cap_conn_del+0x2f2/0x520 net/bluetooth/l2cap_core.c:1825 hci_disconn_cfm include/net/bluetooth/hci_core.h:2152 [inline] hci_conn_hash_flush+0x105/0x260 net/bluetooth/hci_conn.c:2733 hci_dev_close_sync+0x7fc/0x10a0 net/bluetooth/hci_sync.c:5381 hci_dev_do_close net/bluetooth/hci_core.c:502 [inline] hci_unregister_dev+0x232/0x5b0 net/bluetooth/hci_core.c:2681 vhci_release+0x170/0x1c0 drivers/bluetooth/hci_vhci.c:700 __fput+0x42a/0xa80 fs/file_table.c:512 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x73a/0x2360 kernel/exit.c:1004 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147 get_signal+0x121b/0x12c0 kernel/signal.c:3024 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: eccb:0xe4a421182f13d611 Code: Unable to access opcode bytes at 0xe4a421182f13d5e7. RSP: 002b:00007f470d3b5f58 EFLAGS: 00000756 ORIG_RAX: d1d66dbfed01019b RAX: 2bf9e1987c4f44ee RBX: 6f67a894836fe1f3 RCX: ed0b474b2b46640f RDX: fb381f0b5e12d2ce RSI: 401aaa756d8c34aa RDI: 30b9ec15aecde911 RBP: 532828f82bbb556c R08: dbce39d105fdbf88 R09: ae9ea378b9c9fbc7 R10: 33740f3b8630618c R11: 2450ade207355af5 R12: 0a61688f027fb1a4 R13: 339c71c774e61334 R14: 28baed4a0483d193 R15: 7c1f9cf2b758efdc Allocated by task 11998: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5336 [inline] __kmalloc_noprof+0x415/0x790 mm/slub.c:5361 _kmalloc_noprof include/linux/slab.h:973 [inline] tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776 security_file_open+0x9c/0x200 security/security.c:2739 do_dentry_open+0x4be/0x1420 fs/open.c:924 vfs_open+0x3b/0x350 fs/open.c:1052 do_open fs/namei.c:4694 [inline] path_openat+0x2e64/0x3850 fs/namei.c:4857 do_file_open+0x23e/0x4a0 fs/namei.c:4886 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 11998: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2705 [inline] slab_free mm/slub.c:6381 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6696 tomoyo_realpath_from_path+0x605/0x640 security/tomoyo/realpath.c:286 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776 security_file_open+0x9c/0x200 security/security.c:2739 do_dentry_open+0x4be/0x1420 fs/open.c:924 vfs_open+0x3b/0x350 fs/open.c:1052 do_open fs/namei.c:4694 [inline] path_openat+0x2e64/0x3850 fs/namei.c:4857 do_file_open+0x23e/0x4a0 fs/namei.c:4886 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802c32e000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2024 bytes inside of freed 4096-byte region [ffff88802c32e000, ffff88802c32f000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2c328 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813fe3a140 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813fe3a140 dead000000000100 dead000000000122 head: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000 head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: 0000000000000000 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4963, tgid 4963 (udevd), ts 47458126937 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1861 prep_new_page mm/page_alloc.c:1869 [inline] get_page_from_freelist+0x264c/0x26c0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x1a6/0x390 mm/page_alloc.c:5313 alloc_slab_page mm/slub.c:3294 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3408 new_slab mm/slub.c:3454 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7314 refill_sheaf mm/slub.c:2832 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4697 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4907 [inline] __do_kmalloc_node mm/slub.c:5335 [inline] __kmalloc_noprof+0x543/0x790 mm/slub.c:5361 _kmalloc_noprof include/linux/slab.h:973 [inline] tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776 security_file_open+0x9c/0x200 security/security.c:2739 do_dentry_open+0x4be/0x1420 fs/open.c:924 vfs_open+0x3b/0x350 fs/open.c:1052 do_open fs/namei.c:4694 [inline] path_openat+0x2e64/0x3850 fs/namei.c:4857 do_file_open+0x23e/0x4a0 fs/namei.c:4886 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 page last free pid 4963 tgid 4963 ts 47412143657 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1408 [inline] __free_frozen_pages+0x10de/0x11c0 mm/page_alloc.c:2952 __slab_free+0x252/0x2a0 mm/slub.c:5743 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4606 [inline] slab_alloc_node mm/slub.c:4919 [inline] kmem_cache_alloc_noprof+0x358/0x680 mm/slub.c:4933 alloc_empty_file+0x5b/0x1d0 fs/file_table.c:262 path_openat+0x8f/0x3850 fs/namei.c:4843 do_file_open+0x23e/0x4a0 fs/namei.c:4886 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802c32e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802c32e700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802c32e780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802c32e800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802c32e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================