================================================================== BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x92/0x190 lib/list_debug.c:62 Read of size 8 at addr ffff88806c98e558 by task syz.7.1523/11510 CPU: 0 UID: 0 PID: 11510 Comm: syz.7.1523 Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 __list_del_entry_valid_or_report+0x92/0x190 lib/list_debug.c:62 __list_del_entry_valid include/linux/list.h:124 [inline] __list_del_entry include/linux/list.h:215 [inline] list_del_init include/linux/list.h:287 [inline] bt_accept_unlink+0x39/0x240 net/bluetooth/af_bluetooth.c:256 l2cap_sock_teardown_cb+0x17e/0x460 net/bluetooth/l2cap_sock.c:1613 l2cap_chan_del+0xb5/0x5e0 net/bluetooth/l2cap_core.c:655 l2cap_conn_del+0x388/0x680 net/bluetooth/l2cap_core.c:1786 hci_disconn_cfm include/net/bluetooth/hci_core.h:2068 [inline] hci_conn_hash_flush+0x10d/0x230 net/bluetooth/hci_conn.c:2534 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5225 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_unregister_dev+0x206/0x500 net/bluetooth/hci_core.c:2678 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665 __fput+0x44c/0xa70 fs/file_table.c:465 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x8d6/0x2550 kernel/exit.c:953 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fce6f7c1225 Code: Unable to access opcode bytes at 0x7fce6f7c11fb. RSP: 002b:00007fce70534f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007fce6f9b6080 RCX: 00007fce6f7c1225 RDX: 00007fce70534fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fce6f810ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fce6f9b6080 R15: 00007ffc0d9994e8 Allocated by task 12589: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] uevent_show+0x15a/0x310 drivers/base/core.c:2754 dev_attr_show+0x58/0xc0 drivers/base/core.c:2424 sysfs_kf_seq_show+0x310/0x490 fs/sysfs/file.c:65 seq_read_iter+0x4ea/0xe10 fs/seq_file.c:230 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4d0/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 12589: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x193/0x440 mm/slub.c:4841 uevent_show+0x1d5/0x310 drivers/base/core.c:2767 dev_attr_show+0x58/0xc0 drivers/base/core.c:2424 sysfs_kf_seq_show+0x310/0x490 fs/sysfs/file.c:65 seq_read_iter+0x4ea/0xe10 fs/seq_file.c:230 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4d0/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88806c98e000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 1368 bytes inside of freed 4096-byte region [ffff88806c98e000, ffff88806c98f000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6c988 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 ffff88801a042140 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a042140 dead000000000100 dead000000000122 head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001b26201 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 11965, tgid 11957 (syz.4.1657), ts 775534668525, free_ts 775226606656 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2450 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2618 new_slab mm/slub.c:2672 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858 __slab_alloc mm/slub.c:3948 [inline] __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x1e8/0x5a0 security/tomoyo/file.c:723 security_file_ioctl+0xcb/0x2d0 security/security.c:2913 __do_sys_ioctl fs/ioctl.c:900 [inline] __se_sys_ioctl+0x47/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5890 tgid 5890 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xb0e/0xcd0 mm/page_alloc.c:2725 discard_slab mm/slub.c:2716 [inline] __put_partials+0x161/0x1c0 mm/slub.c:3185 put_cpu_partial+0x17c/0x250 mm/slub.c:3260 __slab_free+0x2f7/0x400 mm/slub.c:4512 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203 __kernfs_new_node+0xd7/0x7f0 fs/kernfs/dir.c:637 kernfs_new_node+0x102/0x210 fs/kernfs/dir.c:713 kernfs_create_dir_ns+0x44/0x130 fs/kernfs/dir.c:1081 internal_create_group+0x419/0x1110 fs/sysfs/group.c:170 dpm_sysfs_add+0x6a/0x270 drivers/base/power/sysfs.c:702 device_add+0x4d8/0xb50 drivers/base/core.c:3652 device_create_groups_vargs drivers/base/core.c:4374 [inline] device_create+0x25b/0x2f0 drivers/base/core.c:4413 sound_insert_unit+0x6c4/0x720 sound/sound_core.c:280 Memory state around the buggy address: ffff88806c98e400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806c98e480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806c98e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806c98e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806c98e600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================