================================================================== BUG: KASAN: use-after-free in primary_event_id kernel/events/core.c:1316 [inline] BUG: KASAN: use-after-free in perf_output_read_group kernel/events/core.c:5895 [inline] BUG: KASAN: use-after-free in perf_output_read+0x1046/0x1090 kernel/events/core.c:5930 Read of size 8 at addr ffff8880abfceda0 by task syz-executor.0/18931 CPU: 1 PID: 18931 Comm: syz-executor.0 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 primary_event_id kernel/events/core.c:1316 [inline] perf_output_read_group kernel/events/core.c:5895 [inline] perf_output_read+0x1046/0x1090 kernel/events/core.c:5930 perf_output_sample+0xa28/0x16f0 kernel/events/core.c:5972 __perf_event_output kernel/events/core.c:6285 [inline] perf_event_output_forward+0xf8/0x1f0 kernel/events/core.c:6298 __perf_event_overflow+0x113/0x310 kernel/events/core.c:7547 perf_swevent_overflow kernel/events/core.c:7623 [inline] perf_swevent_event+0x299/0x460 kernel/events/core.c:7651 do_perf_sw_event kernel/events/core.c:7764 [inline] ___perf_sw_event+0x2a1/0x480 kernel/events/core.c:7795 __perf_sw_event+0x4f/0x100 kernel/events/core.c:7807 perf_sw_event include/linux/perf_event.h:1046 [inline] __do_page_fault+0x692/0xad0 arch/x86/mm/fault.c:1483 page_fault+0x25/0x50 arch/x86/entry/entry_64.S:1123 RIP: 0010:copy_user_enhanced_fast_string+0xe/0x20 arch/x86/lib/copy_user_64.S:181 RSP: 0018:ffff8880487a7a78 EFLAGS: 00010206 RAX: ffffed10091d8000 RBX: 0000000000008000 RCX: 0000000000000acb RDX: 0000000000008000 RSI: 0000000020fad000 RDI: ffff888048ebf535 RBP: 0000000020fa5acb R08: 0000000000000001 R09: ffffed10091d7fff R10: ffff888048ebffff R11: 0000000000000000 R12: ffff888048eb8000 R13: 00007ffffffff000 R14: 0000000020fadacb R15: ffff888048eb8000 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:55 [inline] copyin+0x99/0xc0 lib/iov_iter.c:146 _copy_from_iter_full+0x197/0x690 lib/iov_iter.c:608 copy_from_iter_full include/linux/uio.h:126 [inline] skb_do_copy_data_nocache include/net/sock.h:1889 [inline] skb_copy_to_page_nocache include/net/sock.h:1915 [inline] tcp_sendmsg_locked+0x23fc/0x2ef0 net/ipv4/tcp.c:1360 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1457 inet_sendmsg+0x11a/0x4e0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1c7/0x2c0 net/socket.c:1731 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4665d9 RSP: 002b:00007f7d61567188 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665d9 RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000007 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000053 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd35e5e97f R14: 00007f7d61567300 R15: 0000000000022000 Allocated by task 12147: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node_track_caller+0x4c/0x70 mm/slab.c:3696 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0x96/0x510 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:980 [inline] alloc_skb_with_frags+0x85/0x500 net/core/skbuff.c:5255 sock_alloc_send_pskb+0x577/0x6d0 net/core/sock.c:2083 bt_skb_send_alloc include/net/bluetooth/bluetooth.h:347 [inline] l2cap_sock_alloc_skb_cb+0xa6/0x3c0 net/bluetooth/l2cap_sock.c:1398 l2cap_create_basic_pdu net/bluetooth/l2cap_core.c:2236 [inline] l2cap_chan_send+0x25b/0x37f0 net/bluetooth/l2cap_core.c:2532 l2cap_sock_sendmsg+0x1cd/0x280 net/bluetooth/l2cap_sock.c:975 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x326/0x800 net/socket.c:2062 __sys_sendmmsg+0x129/0x330 net/socket.c:2152 SYSC_sendmmsg net/socket.c:2183 [inline] SyS_sendmmsg+0x2f/0x50 net/socket.c:2178 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 14381: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 skb_free_head net/core/skbuff.c:563 [inline] skb_release_data+0x5f6/0x820 net/core/skbuff.c:583 skb_release_all net/core/skbuff.c:640 [inline] __kfree_skb net/core/skbuff.c:654 [inline] kfree_skb+0xe7/0x390 net/core/skbuff.c:672 skb_queue_purge+0x14/0x30 net/core/skbuff.c:2870 hci_chan_del+0x12f/0x1e0 net/bluetooth/hci_conn.c:1578 l2cap_conn_del+0x426/0x690 net/bluetooth/l2cap_core.c:1739 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7441 [inline] l2cap_disconn_cfm+0x7c/0xb0 net/bluetooth/l2cap_core.c:7434 hci_disconn_cfm include/net/bluetooth/hci_core.h:1226 [inline] hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1393 hci_dev_do_close+0x535/0xca0 net/bluetooth/hci_core.c:1622 hci_unregister_dev+0x17f/0x8c0 net/bluetooth/hci_core.c:3193 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xa44/0x2850 kernel/exit.c:868 do_group_exit+0x100/0x2e0 kernel/exit.c:965 get_signal+0x38d/0x1ca0 kernel/signal.c:2423 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff8880abfced40 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 96 bytes inside of 512-byte region [ffff8880abfced40, ffff8880abfcef40) The buggy address belongs to the page: page:ffffea0002aff380 count:1 mapcount:0 mapping:ffff8880abfce0c0 index:0xffff8880abfced40 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffff8880abfce0c0 ffff8880abfced40 0000000100000004 raw: ffffea00023ca0a0 ffffea0002ad52a0 ffff88813fe80940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880abfcec80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880abfced00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8880abfced80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880abfcee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880abfcee80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================