================================================================== BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1d4/0x200 lib/list_debug.c:62 Read of size 8 at addr ffff88805b9ef550 by task syz.4.304/7189 CPU: 1 UID: 0 PID: 7189 Comm: syz.4.304 Not tainted 6.15.0-rc1-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 __list_del_entry_valid_or_report+0x1d4/0x200 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+0x34/0x2e0 net/bluetooth/af_bluetooth.c:256 l2cap_sock_teardown_cb+0x1a3/0x3c0 net/bluetooth/l2cap_sock.c:1613 l2cap_chan_del+0xba/0x8f0 net/bluetooth/l2cap_core.c:655 l2cap_conn_del+0x37a/0x730 net/bluetooth/l2cap_core.c:1786 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7299 [inline] l2cap_disconn_cfm+0x96/0xd0 net/bluetooth/l2cap_core.c:7292 hci_disconn_cfm include/net/bluetooth/hci_core.h:2069 [inline] hci_conn_hash_flush+0x10b/0x260 net/bluetooth/hci_conn.c:2701 hci_dev_close_sync+0x602/0x11d0 net/bluetooth/hci_sync.c:5225 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:483 hci_unregister_dev+0x213/0x620 net/bluetooth/hci_core.c:2678 vhci_release+0x79/0xf0 drivers/bluetooth/hci_vhci.c:665 __fput+0x3ff/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xafb/0x2c30 kernel/exit.c:953 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102 get_signal+0x2673/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7d0 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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0094dbfa25 Code: Unable to access opcode bytes at 0x7f0094dbf9fb. RSP: 002b:00007f0092bd4f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f0094fa6080 RCX: 00007f0094dbfa25 RDX: 00007f0092bd4fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f0094e0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0094fa6080 R15: 00007ffeb862a878 Allocated by task 8290: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4331 [inline] __kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4350 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:599 __alloc_skb+0x166/0x380 net/core/skbuff.c:668 skb_copy_expand+0x1d0/0x410 net/core/skbuff.c:2471 sctp_ulpevent_make_send_failed_event+0x58/0xb50 net/sctp/ulpevent.c:542 sctp_datamsg_destroy net/sctp/chunk.c:104 [inline] sctp_datamsg_put+0x40a/0x5f0 net/sctp/chunk.c:128 sctp_chunk_free+0x45/0x60 net/sctp/sm_make_chunk.c:1515 __sctp_outq_teardown+0x70a/0xc40 net/sctp/outqueue.c:257 sctp_association_free+0x210/0x7e0 net/sctp/associola.c:340 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:944 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1330 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x22dc/0x5c80 net/sctp/sm_sideeffect.c:1169 sctp_primitive_SHUTDOWN+0x9f/0xd0 net/sctp/primitive.c:89 sctp_shutdown+0x137/0x180 net/sctp/socket.c:5165 inet_shutdown+0x1a2/0x440 net/ipv4/af_inet.c:923 __sys_shutdown_sock net/socket.c:2406 [inline] __sys_shutdown_sock net/socket.c:2400 [inline] __sys_shutdown+0x113/0x1a0 net/socket.c:2422 __do_sys_shutdown net/socket.c:2427 [inline] __se_sys_shutdown net/socket.c:2425 [inline] __x64_sys_shutdown+0x53/0x80 net/socket.c:2425 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 8283: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2389 [inline] slab_free mm/slub.c:4646 [inline] kfree+0x2b6/0x4d0 mm/slub.c:4845 skb_kfree_head net/core/skbuff.c:1058 [inline] skb_free_head+0x108/0x1d0 net/core/skbuff.c:1070 skb_release_data+0x7a5/0x960 net/core/skbuff.c:1097 skb_release_all net/core/skbuff.c:1162 [inline] __kfree_skb net/core/skbuff.c:1176 [inline] sk_skb_reason_drop+0x129/0x1a0 net/core/skbuff.c:1214 sctp_queue_purge_ulpevents+0xb8/0x100 net/sctp/ulpevent.c:1186 sctp_close+0x13b/0x940 net/sctp/socket.c:1500 inet_release+0x13c/0x280 net/ipv4/af_inet.c:435 inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:487 __sock_release+0xb0/0x270 net/socket.c:647 sock_close+0x1c/0x30 net/socket.c:1391 __fput+0x3ff/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805b9ef000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1360 bytes inside of freed 2048-byte region [ffff88805b9ef000, ffff88805b9ef800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5b9e8 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 ffff88801b442000 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b442000 0000000000000000 dead000000000001 head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea00016e7a01 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 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5820, tgid 5820 (syz-executor), ts 62713176711, free_ts 14286817355 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1717 prep_new_page mm/page_alloc.c:1725 [inline] get_page_from_freelist+0x1193/0x39b0 mm/page_alloc.c:3652 __alloc_frozen_pages_noprof+0x263/0x23a0 mm/page_alloc.c:4934 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2459 [inline] allocate_slab mm/slub.c:2623 [inline] new_slab+0x23c/0x330 mm/slub.c:2676 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3862 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3952 __slab_alloc_node mm/slub.c:4027 [inline] slab_alloc_node mm/slub.c:4188 [inline] __do_kmalloc_node mm/slub.c:4330 [inline] __kmalloc_node_track_caller_noprof+0x2ee/0x510 mm/slub.c:4350 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:599 pskb_expand_head+0x22d/0x10b0 net/core/skbuff.c:2247 netlink_trim+0x22d/0x310 net/netlink/af_netlink.c:1295 netlink_broadcast_filtered+0xca/0xf10 net/netlink/af_netlink.c:1501 nlmsg_multicast_filtered include/net/netlink.h:1129 [inline] nlmsg_multicast include/net/netlink.h:1148 [inline] nlmsg_notify+0x9e/0x220 net/netlink/af_netlink.c:2577 rtnl_notify net/core/rtnetlink.c:958 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:4429 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4445 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4432 [inline] rtnetlink_event+0x177/0x1f0 net/core/rtnetlink.c:7015 notifier_call_chain+0xb9/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2183 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+0x69d/0xff0 mm/page_alloc.c:2680 __free_pages mm/page_alloc.c:5044 [inline] free_contig_range+0x135/0x3f0 mm/page_alloc.c:6900 destroy_args+0x66f/0x830 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x130e/0x2d50 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x120/0x6e0 init/main.c:1257 do_initcall_level init/main.c:1319 [inline] do_initcalls init/main.c:1335 [inline] do_basic_setup init/main.c:1354 [inline] kernel_init_freeable+0x5c2/0x900 init/main.c:1567 kernel_init+0x1c/0x2b0 init/main.c:1457 ret_from_fork+0x45/0x80 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: ffff88805b9ef400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b9ef480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805b9ef500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805b9ef580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b9ef600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================