================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_ready_cb+0x191/0x1a0 net/bluetooth/l2cap_sock.c:1711 Read of size 8 at addr ffff88802bda7188 by task kworker/u33:3/5942 CPU: 0 UID: 0 PID: 5942 Comm: kworker/u33:3 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: hci4 hci_rx_work 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+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595 l2cap_sock_ready_cb+0x191/0x1a0 net/bluetooth/l2cap_sock.c:1711 l2cap_chan_ready net/bluetooth/l2cap_core.c:1239 [inline] l2cap_le_start+0x1ea/0xea0 net/bluetooth/l2cap_core.c:1368 l2cap_conn_ready net/bluetooth/l2cap_core.c:1621 [inline] l2cap_connect_cfm+0x8ce/0x1050 net/bluetooth/l2cap_core.c:7368 hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline] le_conn_complete_evt+0x195c/0x1f40 net/bluetooth/hci_event.c:5847 hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5873 hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7473 hci_event_func net/bluetooth/hci_event.c:7781 [inline] hci_event_packet+0x682/0x11c0 net/bluetooth/hci_event.c:7838 hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 18719: 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 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5238 [inline] __kmalloc_noprof+0x301/0x850 mm/slub.c:5250 kmalloc_noprof include/linux/slab.h:954 [inline] sk_prot_alloc+0x10b/0x2a0 net/core/sock.c:2245 sk_alloc+0x36/0xe80 net/core/sock.c:2301 bt_sock_alloc+0x3b/0x3a0 net/bluetooth/af_bluetooth.c:151 l2cap_sock_alloc.constprop.0+0x33/0x1e0 net/bluetooth/l2cap_sock.c:1922 l2cap_sock_create+0x123/0x210 net/bluetooth/l2cap_sock.c:1964 bt_sock_create+0x185/0x350 net/bluetooth/af_bluetooth.c:135 __sock_create+0x339/0x860 net/socket.c:1605 sock_create net/socket.c:1663 [inline] __sys_socket_create net/socket.c:1700 [inline] __sys_socket+0x14d/0x260 net/socket.c:1747 __do_sys_socket net/socket.c:1761 [inline] __se_sys_socket net/socket.c:1759 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1759 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 18718: 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:2692 [inline] slab_free mm/slub.c:6143 [inline] kfree+0x1f6/0x6b0 mm/slub.c:6461 sk_prot_free net/core/sock.c:2284 [inline] __sk_destruct+0x8ab/0xbb0 net/core/sock.c:2384 sk_destruct+0xc8/0xf0 net/core/sock.c:2412 __sk_free+0xf4/0x3e0 net/core/sock.c:2423 sk_free+0x61/0x90 net/core/sock.c:2434 sock_put include/net/sock.h:2007 [inline] l2cap_sock_kill net/bluetooth/l2cap_sock.c:1290 [inline] l2cap_sock_kill+0x176/0x310 net/bluetooth/l2cap_sock.c:1275 l2cap_sock_release+0x1cb/0x280 net/bluetooth/l2cap_sock.c:1463 __sock_release+0xb3/0x260 net/socket.c:662 sock_close+0x1c/0x30 net/socket.c:1455 __fput+0x3ff/0xb40 fs/file_table.c:469 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802bda7000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 392 bytes inside of freed 2048-byte region [ffff88802bda7000, ffff88802bda7800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2bda0 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 ffff88801b842f00 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b842f00 dead000000000100 dead000000000122 head: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000af6801 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 105, tgid 105 (kworker/u32:5), ts 12510247967, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3269 [inline] allocate_slab mm/slub.c:3458 [inline] new_slab+0xa6/0x6d0 mm/slub.c:3516 refill_objects+0x26b/0x400 mm/slub.c:7153 refill_sheaf mm/slub.c:2818 [inline] alloc_full_sheaf mm/slub.c:2839 [inline] __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4602 alloc_from_pcs mm/slub.c:4695 [inline] slab_alloc_node mm/slub.c:4829 [inline] __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5353 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] bsg_register_queue+0x52/0x400 block/bsg.c:195 scsi_sysfs_add_sdev+0x2d9/0x590 drivers/scsi/scsi_sysfs.c:1429 scsi_add_lun+0x16ec/0x1ce0 drivers/scsi/scsi_scan.c:1130 scsi_probe_and_add_lun+0x52f/0xe00 drivers/scsi/scsi_scan.c:1301 __scsi_add_device+0x249/0x280 drivers/scsi/scsi_scan.c:1636 ata_scsi_scan_host+0x1e7/0x6e0 drivers/ata/libata-scsi.c:4699 async_run_entry_fn+0x9f/0x580 kernel/async.c:129 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 page_owner free stack trace missing Memory state around the buggy address: ffff88802bda7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802bda7100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802bda7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802bda7200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802bda7280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================