syzbot

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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 ffff88807d702558 by task syz-executor/5848

CPU: 0 UID: 0 PID: 5848 Comm: syz-executor Not tainted 6.16.0-rc5-syzkaller-00266-g3f31a806a62e #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x230 mm/kasan/report.c:480
 kasan_report+0x118/0x150 mm/kasan/report.c:593
 __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:259
 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:1787
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2070 [inline]
 hci_conn_hash_flush+0x10d/0x230 net/bluetooth/hci_conn.c:2560
 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5294
 hci_dev_do_close net/bluetooth/hci_core.c:501 [inline]
 hci_unregister_dev+0x21a/0x510 net/bluetooth/hci_core.c:2717
 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+0x6b5/0x22e0 kernel/exit.c:964
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
 __do_sys_exit_group kernel/exit.c:1116 [inline]
 __se_sys_exit_group kernel/exit.c:1114 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1114
 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb30b8e929
Code: Unable to access opcode bytes at 0x7feb30b8e8ff.
RSP: 002b:00007ffd6b3d25d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007feb30c1094a RCX: 00007feb30b8e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000002 R08: 00007ffd6b3d0377 R09: 00007ffd6b3d3890
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd6b3d3890
R13: 00007feb30c10925 R14: 000000000016221d R15: 00007ffd6b3d4960
 </TASK>

Allocated by task 15476:
 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]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4347
 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1336 [inline]
 _sctp_make_chunk+0x5e/0x430 net/sctp/sm_make_chunk.c:1435
 sctp_make_data net/sctp/sm_make_chunk.c:1467 [inline]
 sctp_make_datafrag_empty+0x122/0x230 net/sctp/sm_make_chunk.c:732
 sctp_datamsg_from_user+0x729/0xef0 net/sctp/chunk.c:262
 sctp_sendmsg_to_asoc+0x1003/0x1810 net/sctp/socket.c:1860
 sctp_sendmsg+0x1941/0x2810 net/sctp/socket.c:2032
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x19c/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 15477:
 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:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kfree+0x18e/0x440 mm/slub.c:4842
 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1087
 skb_release_all net/core/skbuff.c:1152 [inline]
 __kfree_skb net/core/skbuff.c:1166 [inline]
 consume_skb+0x9e/0xf0 net/core/skbuff.c:1398
 sctp_chunk_destroy net/sctp/sm_make_chunk.c:1495 [inline]
 sctp_chunk_put+0x17d/0x200 net/sctp/sm_make_chunk.c:1522
 sctp_datamsg_destroy net/sctp/chunk.c:-1 [inline]
 sctp_datamsg_put+0x409/0x540 net/sctp/chunk.c:128
 sctp_chunk_free+0x4a/0x60 net/sctp/sm_make_chunk.c:1507
 __sctp_outq_teardown+0x7ab/0x9a0 net/sctp/outqueue.c:257
 sctp_association_free+0x240/0x7f0 net/sctp/associola.c:340
 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:950 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1336 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1204 [inline]
 sctp_do_sm+0x3eba/0x5a20 net/sctp/sm_sideeffect.c:1175
 sctp_primitive_SHUTDOWN+0x98/0xc0 net/sctp/primitive.c:89
 inet_shutdown+0x271/0x390 net/ipv4/af_inet.c:923
 __sys_shutdown_sock net/socket.c:2406 [inline]
 __sys_shutdown net/socket.c:2422 [inline]
 __do_sys_shutdown net/socket.c:2427 [inline]
 __se_sys_shutdown net/socket.c:2425 [inline]
 __x64_sys_shutdown+0x13f/0x1a0 net/socket.c:2425
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807d702000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1368 bytes inside of
 freed 2048-byte region [ffff88807d702000, ffff88807d702800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d702000 pfn:0x7d700
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 ffff88801a442000 ffffea0001686010 ffffea00019ee210
raw: ffff88807d702000 0000000000080006 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a442000 ffffea0001686010 ffffea00019ee210
head: ffff88807d702000 0000000000080006 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001f5c001 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 5840, tgid 5840 (syz-executor), ts 92746768642, free_ts 92697053143
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2619
 new_slab mm/slub.c:2673 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859
 __slab_alloc mm/slub.c:3949 [inline]
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kvmalloc_node_noprof+0x429/0x5f0 mm/slub.c:5015
 kvmalloc_array_node_noprof include/linux/slab.h:1065 [inline]
 __ptr_ring_init_queue_alloc_noprof include/linux/ptr_ring.h:471 [inline]
 ptr_ring_init_noprof include/linux/ptr_ring.h:489 [inline]
 page_pool_init net/core/page_pool.c:266 [inline]
 page_pool_create_percpu+0x32a/0xbe0 net/core/page_pool.c:345
 nsim_create_page_pool drivers/net/netdevsim/netdev.c:393 [inline]
 nsim_init_napi drivers/net/netdevsim/netdev.c:416 [inline]
 nsim_open+0x3ba/0x860 drivers/net/netdevsim/netdev.c:471
 __dev_open+0x470/0x880 net/core/dev.c:1683
 __dev_change_flags+0x1ea/0x6d0 net/core/dev.c:9458
 netif_change_flags+0x88/0x1a0 net/core/dev.c:9521
 do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3141
 rtnl_changelink net/core/rtnetlink.c:3759 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
 rtnl_newlink+0x160b/0x1c70 net/core/rtnetlink.c:4055
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6944
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
page last free pid 5845 tgid 5845 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 __slab_free+0x326/0x400 mm/slub.c:4554
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 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:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kvmalloc_node_noprof+0x2b0/0x5f0 mm/slub.c:5015
 alloc_netdev_mqs+0xa6/0x11e0 net/core/dev.c:11711
 rtnl_create_link+0x31f/0xd10 net/core/rtnetlink.c:3631
 rtnl_newlink_create+0x25c/0xb00 net/core/rtnetlink.c:3813
 __rtnl_newlink net/core/rtnetlink.c:3940 [inline]
 rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4055
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6944
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180

Memory state around the buggy address:
 ffff88807d702400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d702480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807d702500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88807d702580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d702600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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