================================================================== BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62 Read of size 8 at addr ffff88802cffd578 by task syz.1.3124/17769 CPU: 0 UID: 0 PID: 17769 Comm: syz.1.3124 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1d0 mm/kasan/report.c:595 __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62 __list_del_entry_valid include/linux/list.h:132 [inline] __list_del_entry include/linux/list.h:223 [inline] list_del_init include/linux/list.h:295 [inline] bt_accept_unlink+0x34/0x2f0 net/bluetooth/af_bluetooth.c:259 l2cap_sock_teardown_cb+0x1a3/0x3f0 net/bluetooth/l2cap_sock.c:1640 l2cap_chan_del+0xbd/0x930 net/bluetooth/l2cap_core.c:656 l2cap_conn_del+0x395/0x710 net/bluetooth/l2cap_core.c:1802 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7448 [inline] l2cap_disconn_cfm+0x9f/0x100 net/bluetooth/l2cap_core.c:7441 hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline] hci_conn_hash_flush+0x10e/0x280 net/bluetooth/hci_conn.c:2650 hci_dev_close_sync+0x5a7/0x1240 net/bluetooth/hci_sync.c:5368 hci_dev_do_close+0x2e/0xb0 net/bluetooth/hci_core.c:502 hci_unregister_dev+0x227/0x670 net/bluetooth/hci_core.c:2716 vhci_release+0x17d/0x230 drivers/bluetooth/hci_vhci.c:690 __fput+0x3ff/0xb50 fs/file_table.c:510 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x8d2/0x2a60 kernel/exit.c:975 do_group_exit+0xd5/0x2a0 kernel/exit.c:1117 get_signal+0x1ec7/0x21e0 kernel/signal.c:3037 arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98 __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:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x706/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fadedf9cdd9 Code: Unable to access opcode bytes at 0x7fadedf9cdaf. RSP: 002b:00007ffed159c108 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fadee217da0 RCX: 00007fadedf9cdd9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fadee217da0 R08: 00007fadee216038 R09: 0000000000000000 R10: 00000000005d5b0c R11: 0000000000000246 R12: 000000000011f6ee R13: 00007fadee215fac R14: 000000000011f689 R15: 00007ffed159c210 Allocated by task 4966: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:950 [inline] syslog_print+0xf8/0x620 kernel/printk/printk.c:1585 do_syslog+0x5bd/0x6d0 kernel/printk/printk.c:1763 __do_sys_syslog kernel/printk/printk.c:1855 [inline] __se_sys_syslog kernel/printk/printk.c:1853 [inline] __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1853 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 4966: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x223/0x6c0 mm/slub.c:6561 syslog_print+0x548/0x620 kernel/printk/printk.c:1677 do_syslog+0x5bd/0x6d0 kernel/printk/printk.c:1763 __do_sys_syslog kernel/printk/printk.c:1855 [inline] __se_sys_syslog kernel/printk/printk.c:1853 [inline] __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1853 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802cffd000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1400 bytes inside of freed 2048-byte region [ffff88802cffd000, ffff88802cffd800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802cffe000 pfn:0x2cff8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88813fe35000 ffffea000070d210 ffffea0001570010 raw: ffff88802cffe000 0000000800080001 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88813fe35000 ffffea000070d210 ffffea0001570010 head: ffff88802cffe000 0000000800080001 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 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 5604, tgid 5604 (syz-executor), ts 70409516758, free_ts 38818440348 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab mm/slub.c:3467 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3525 refill_objects+0x277/0x420 mm/slub.c:7251 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_noprof+0x688/0x850 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] genl_family_rcv_msg_attrs_parse.isra.0+0x100/0x2f0 net/netlink/genetlink.c:936 genl_start+0x18f/0x970 net/netlink/genetlink.c:979 __netlink_dump_start+0x60e/0x990 net/netlink/af_netlink.c:2431 genl_family_rcv_msg_dumpit+0x1e2/0x2e0 net/netlink/genetlink.c:1075 genl_family_rcv_msg net/netlink/genetlink.c:1191 [inline] genl_rcv_msg+0x471/0x800 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894 page last free pid 5327 tgid 5327 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0x747/0x1040 mm/page_alloc.c:2943 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_noprof+0x2b9/0x850 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] tomoyo_realpath_from_path+0xb6/0x690 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827 security_inode_getattr+0x116/0x280 security/security.c:1895 vfs_getattr fs/stat.c:259 [inline] vfs_fstat+0x4b/0xe0 fs/stat.c:281 __do_sys_newfstat+0x8b/0x110 fs/stat.c:551 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802cffd400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802cffd480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802cffd500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802cffd580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802cffd600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================