================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_ready_cb+0x16a/0x170 net/bluetooth/l2cap_sock.c:1670 Read of size 8 at addr ffff888056b5d188 by task kworker/u33:5/5930 CPU: 1 UID: 0 PID: 5930 Comm: kworker/u33:5 Not tainted 6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: hci1 hci_rx_work 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:378 [inline] print_report+0xc3/0x620 mm/kasan/report.c:489 kasan_report+0xd9/0x110 mm/kasan/report.c:602 l2cap_sock_ready_cb+0x16a/0x170 net/bluetooth/l2cap_sock.c:1670 l2cap_chan_ready net/bluetooth/l2cap_core.c:1239 [inline] l2cap_le_start+0x1ec/0xe40 net/bluetooth/l2cap_core.c:1368 l2cap_conn_ready net/bluetooth/l2cap_core.c:1624 [inline] l2cap_connect_cfm+0x8f9/0xf80 net/bluetooth/l2cap_core.c:7278 hci_connect_cfm include/net/bluetooth/hci_core.h:2035 [inline] le_conn_complete_evt+0x1658/0x1d60 net/bluetooth/hci_event.c:5763 hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5789 hci_le_meta_evt+0x2e2/0x5d0 net/bluetooth/hci_event.c:7173 hci_event_func net/bluetooth/hci_event.c:7481 [inline] hci_event_packet+0x666/0x1180 net/bluetooth/hci_event.c:7536 hci_rx_work+0x2c5/0x16b0 net/bluetooth/hci_core.c:4039 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 11930: 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:4283 [inline] __kmalloc_noprof+0x21c/0x510 mm/slub.c:4295 kmalloc_noprof include/linux/slab.h:905 [inline] sk_prot_alloc+0x1a8/0x2a0 net/core/sock.c:2165 sk_alloc+0x36/0xb90 net/core/sock.c:2218 bt_sock_alloc+0x3b/0x3a0 net/bluetooth/af_bluetooth.c:148 l2cap_sock_alloc.constprop.0+0x33/0x1c0 net/bluetooth/l2cap_sock.c:1877 l2cap_sock_create+0x123/0x1f0 net/bluetooth/l2cap_sock.c:1918 bt_sock_create+0x182/0x350 net/bluetooth/af_bluetooth.c:132 __sock_create+0x335/0x8d0 net/socket.c:1558 sock_create net/socket.c:1616 [inline] __sys_socket_create net/socket.c:1653 [inline] __sys_socket+0x14f/0x260 net/socket.c:1700 __do_sys_socket net/socket.c:1714 [inline] __se_sys_socket net/socket.c:1712 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1712 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 11929: 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:582 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:2338 [inline] slab_free mm/slub.c:4598 [inline] kfree+0x14f/0x4b0 mm/slub.c:4746 sk_prot_free net/core/sock.c:2201 [inline] __sk_destruct+0x5eb/0x720 net/core/sock.c:2293 sk_destruct+0xc2/0xf0 net/core/sock.c:2308 __sk_free+0xf4/0x3e0 net/core/sock.c:2319 sk_free+0x6a/0x90 net/core/sock.c:2330 sock_put include/net/sock.h:1904 [inline] l2cap_sock_kill net/bluetooth/l2cap_sock.c:1250 [inline] l2cap_sock_kill+0x171/0x2d0 net/bluetooth/l2cap_sock.c:1235 l2cap_sock_release+0x189/0x210 net/bluetooth/l2cap_sock.c:1421 __sock_release+0xb0/0x270 net/socket.c:640 sock_close+0x1c/0x30 net/socket.c:1408 __fput+0x3f8/0xb60 fs/file_table.c:450 task_work_run+0x14e/0x250 kernel/task_work.c:239 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 ffff888056b5d000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 392 bytes inside of freed 2048-byte region [ffff888056b5d000, ffff888056b5d800) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56b58 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 ffff88801b042f00 ffffea000047c600 dead000000000002 raw: 0000000000000000 0000000000080008 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801b042f00 ffffea000047c600 dead000000000002 head: 0000000000000000 0000000000080008 00000001f5000000 0000000000000000 head: 00fff00000000003 ffffea00015ad601 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10046, tgid 10046 (syz-executor), ts 156190868013, free_ts 114476799274 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3474 __alloc_pages_noprof+0x223/0x25b0 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265 alloc_slab_page mm/slub.c:2408 [inline] allocate_slab mm/slub.c:2574 [inline] new_slab+0x2c9/0x410 mm/slub.c:2627 ___slab_alloc+0xdac/0x1870 mm/slub.c:3815 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3905 __slab_alloc_node mm/slub.c:3980 [inline] slab_alloc_node mm/slub.c:4141 [inline] __kmalloc_cache_noprof+0xfa/0x410 mm/slub.c:4309 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] fib6_net_init net/ipv6/ip6_fib.c:2422 [inline] fib6_net_init+0x1dc/0xb00 net/ipv6/ip6_fib.c:2397 ops_init+0x1df/0x5f0 net/core/net_namespace.c:138 setup_net+0x21f/0x860 net/core/net_namespace.c:362 copy_net_ns+0x2b4/0x6b0 net/core/net_namespace.c:500 create_new_namespaces+0x3ea/0xad0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x45d/0xa40 kernel/fork.c:3334 __do_sys_unshare kernel/fork.c:3405 [inline] __se_sys_unshare kernel/fork.c:3403 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3403 page last free pid 9093 tgid 9092 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0x661/0x1080 mm/page_alloc.c:2657 vfree+0x17a/0x890 mm/vmalloc.c:3382 __vmalloc_area_node mm/vmalloc.c:3732 [inline] __vmalloc_node_range_noprof+0x11c9/0x1530 mm/vmalloc.c:3844 vmalloc_user_noprof+0x6b/0x90 mm/vmalloc.c:3998 vb2_vmalloc_alloc+0x11e/0x3d0 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47 __vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:242 [inline] __vb2_queue_alloc+0x896/0x1230 drivers/media/common/videobuf2/videobuf2-core.c:523 vb2_core_reqbufs+0xa73/0xfb0 drivers/media/common/videobuf2/videobuf2-core.c:964 vb2_ioctl_reqbufs+0x299/0x430 drivers/media/common/videobuf2/videobuf2-v4l2.c:1036 vidioc_reqbufs+0x86/0x100 drivers/media/test-drivers/vivid/vivid-core.c:707 v4l_reqbufs+0x14c/0x1e0 drivers/media/v4l2-core/v4l2-ioctl.c:2159 __video_do_ioctl+0xaf0/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:3122 video_usercopy+0x4d2/0x1620 drivers/media/v4l2-core/v4l2-ioctl.c:3463 v4l2_ioctl+0x1ba/0x250 drivers/media/v4l2-core/v4l2-dev.c:366 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 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 Memory state around the buggy address: ffff888056b5d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888056b5d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888056b5d180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888056b5d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888056b5d280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================