================================================================== BUG: KASAN: slab-use-after-free in force_devcd_write+0x317/0x330 drivers/bluetooth/hci_vhci.c:327 Read of size 8 at addr ffff8880288eb800 by task syz.1.4579/17440 CPU: 1 UID: 0 PID: 17440 Comm: syz.1.4579 Not tainted 6.14.0-rc6-syzkaller #0 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+0xd9/0x110 mm/kasan/report.c:634 force_devcd_write+0x317/0x330 drivers/bluetooth/hci_vhci.c:327 full_proxy_write+0x13c/0x200 fs/debugfs/file.c:398 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3cd7f8d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3cd8d1b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3cd81a6080 RCX: 00007f3cd7f8d169 RDX: 000000000000000e RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f3cd800e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3cd81a6080 R15: 00007ffc12a3e978 Allocated by task 17150: 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 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] sctp_transport_new+0x94/0x790 net/sctp/transport.c:97 sctp_assoc_add_peer+0x2e5/0x1530 net/sctp/associola.c:617 sctp_process_param net/sctp/sm_make_chunk.c:2576 [inline] sctp_process_init+0x2744/0x2d60 net/sctp/sm_make_chunk.c:2396 sctp_cmd_process_init net/sctp/sm_sideeffect.c:706 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1389 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x15df/0x5c90 net/sctp/sm_sideeffect.c:1169 sctp_assoc_bh_rcv+0x392/0x6f0 net/sctp/associola.c:1052 sctp_inq_push+0x1d8/0x270 net/sctp/inqueue.c:88 sctp_backlog_rcv+0x169/0x590 net/sctp/input.c:331 sk_backlog_rcv include/net/sock.h:1122 [inline] __release_sock+0x35f/0x400 net/core/sock.c:3123 release_sock+0x5a/0x220 net/core/sock.c:3677 sctp_wait_for_connect+0x1c6/0x5c0 net/sctp/socket.c:9360 __sctp_connect+0x9c9/0xc60 net/sctp/socket.c:1247 sctp_connect net/sctp/socket.c:4819 [inline] sctp_inet_connect+0x15f/0x200 net/sctp/socket.c:4834 __sys_connect_file+0x13e/0x1a0 net/socket.c:2045 __sys_connect+0x14f/0x170 net/socket.c:2064 __do_sys_connect net/socket.c:2070 [inline] __se_sys_connect net/socket.c:2067 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2067 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 25: 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:2353 [inline] slab_free mm/slub.c:4609 [inline] kfree+0x2c4/0x4d0 mm/slub.c:4757 rcu_do_batch kernel/rcu/tree.c:2546 [inline] rcu_core+0x79d/0x14d0 kernel/rcu/tree.c:2802 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 run_ksoftirqd kernel/softirq.c:950 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:942 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xb8/0xd0 mm/kasan/generic.c:548 __call_rcu_common.constprop.0+0x9a/0x870 kernel/rcu/tree.c:3065 sctp_transport_destroy net/sctp/transport.c:171 [inline] sctp_transport_put+0x10f/0x170 net/sctp/transport.c:484 sctp_association_free+0x4d3/0x7e0 net/sctp/associola.c:380 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+0x22e4/0x5c90 net/sctp/sm_sideeffect.c:1169 sctp_assoc_bh_rcv+0x392/0x6f0 net/sctp/associola.c:1052 sctp_inq_push+0x1d8/0x270 net/sctp/inqueue.c:88 sctp_backlog_rcv+0x169/0x590 net/sctp/input.c:331 sk_backlog_rcv include/net/sock.h:1122 [inline] __release_sock+0x35f/0x400 net/core/sock.c:3123 release_sock+0x5a/0x220 net/core/sock.c:3677 sctp_close+0x44c/0x930 net/sctp/socket.c:1536 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:1398 __fput+0x3ff/0xb70 fs/file_table.c:464 task_work_run+0x14e/0x250 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/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880288eb800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes inside of freed 1024-byte region [ffff8880288eb800, ffff8880288ebc00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880288ea000 pfn:0x288e8 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 ffff88801b041dc0 ffffea0001ee0a10 ffffea0001e2fc10 raw: ffff8880288ea000 000000000010000e 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801b041dc0 ffffea0001ee0a10 ffffea0001e2fc10 head: ffff8880288ea000 000000000010000e 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000a23a01 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 13, tgid 13 (kworker/u8:1), ts 10383242978, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x221/0x2470 mm/page_alloc.c:4740 alloc_slab_page mm/slub.c:2425 [inline] allocate_slab mm/slub.c:2587 [inline] new_slab+0x94/0x330 mm/slub.c:2640 ___slab_alloc+0xc5d/0x1720 mm/slub.c:3826 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] __kmalloc_cache_node_noprof+0x101/0x420 mm/slub.c:4333 kmalloc_node_noprof include/linux/slab.h:924 [inline] blk_mq_alloc_hctx block/blk-mq.c:3945 [inline] blk_mq_alloc_and_init_hctx+0x639/0x11b0 block/blk-mq.c:4448 blk_mq_realloc_hw_ctxs+0x8e0/0xbe0 block/blk-mq.c:4481 blk_mq_init_allocated_queue+0x39e/0x11f0 block/blk-mq.c:4535 blk_mq_alloc_queue+0x1c3/0x290 block/blk-mq.c:4348 scsi_alloc_sdev+0x890/0xd80 drivers/scsi/scsi_scan.c:338 scsi_probe_and_add_lun+0x789/0xda0 drivers/scsi/scsi_scan.c:1209 __scsi_scan_target+0x1ea/0x580 drivers/scsi/scsi_scan.c:1774 scsi_scan_channel drivers/scsi/scsi_scan.c:1862 [inline] scsi_scan_channel+0x149/0x1e0 drivers/scsi/scsi_scan.c:1838 scsi_scan_host_selected+0x302/0x400 drivers/scsi/scsi_scan.c:1891 page_owner free stack trace missing Memory state around the buggy address: ffff8880288eb700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880288eb780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880288eb800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880288eb880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880288eb900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================