================================================================== BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1616 [inline] BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xe57/0x1050 net/bluetooth/l2cap_core.c:7368 Read of size 8 at addr ffff888033195480 by task kworker/u33:0/63 CPU: 1 UID: 0 PID: 63 Comm: kworker/u33:0 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: hci3 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_conn_ready net/bluetooth/l2cap_core.c:1616 [inline] l2cap_connect_cfm+0xe57/0x1050 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:467 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 63: 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 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] l2cap_chan_create+0x44/0x940 net/bluetooth/l2cap_core.c:445 l2cap_sock_alloc.constprop.0+0xf5/0x1e0 net/bluetooth/l2cap_sock.c:1931 l2cap_sock_new_connection_cb+0x101/0x260 net/bluetooth/l2cap_sock.c:1510 l2cap_connect_cfm+0x4e2/0x1050 net/bluetooth/l2cap_core.c:7351 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:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 13315: 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 l2cap_chan_destroy net/bluetooth/l2cap_core.c:491 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_chan_put+0x235/0x300 net/bluetooth/l2cap_core.c:516 l2cap_sock_cleanup_listen+0x4d/0x2d0 net/bluetooth/l2cap_sock.c:1493 l2cap_sock_release+0x69/0x280 net/bluetooth/l2cap_sock.c:1451 __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 ffff888033195000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1152 bytes inside of freed 2048-byte region [ffff888033195000, ffff888033195800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888033194000 pfn:0x33190 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 ffff88801b842f00 ffffea0000d60c10 ffff88801b840948 raw: ffff888033194000 0000000800080007 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801b842f00 ffffea0000d60c10 ffff88801b840948 head: ffff888033194000 0000000800080007 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000cc6401 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 10804, tgid 10803 (syz.1.1719), ts 147705714458, free_ts 147642282268 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] __do_kmalloc_node mm/slub.c:5237 [inline] __kmalloc_noprof+0x688/0x850 mm/slub.c:5250 kmalloc_noprof include/linux/slab.h:954 [inline] sock_kmalloc+0x111/0x170 net/core/sock.c:2880 _skcipher_recvmsg crypto/algif_skcipher.c:144 [inline] skcipher_recvmsg+0x48d/0x1020 crypto/algif_skcipher.c:221 sock_recvmsg_nosec net/socket.c:1078 [inline] sock_recvmsg+0x1f9/0x250 net/socket.c:1100 ____sys_recvmsg+0x218/0x6b0 net/socket.c:2812 ___sys_recvmsg+0x16a/0x1a0 net/socket.c:2854 __sys_recvmsg+0x16d/0x220 net/socket.c:2887 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 page last free pid 5934 tgid 5934 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4515 [inline] slab_alloc_node mm/slub.c:4844 [inline] kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4851 vm_area_dup+0x27/0x8e0 mm/vma_init.c:123 dup_mmap+0x6f6/0x2180 mm/mmap.c:1787 dup_mm kernel/fork.c:1530 [inline] copy_mm kernel/fork.c:1582 [inline] copy_process+0x73d7/0x7a10 kernel/fork.c:2223 kernel_clone+0xfc/0x9a0 kernel/fork.c:2654 __do_sys_clone+0xd9/0x120 kernel/fork.c:2795 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 Memory state around the buggy address: ffff888033195380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888033195400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888033195480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888033195500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888033195580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================