audit: type=1400 audit(1593833304.769:8): avc: denied { execmem } for pid=6333 comm="syz-executor884" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 ================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:347 [inline] BUG: KASAN: slab-out-of-bounds in bacpy include/net/bluetooth/bluetooth.h:233 [inline] BUG: KASAN: slab-out-of-bounds in hci_extended_inquiry_result_evt net/bluetooth/hci_event.c:3840 [inline] BUG: KASAN: slab-out-of-bounds in hci_event_packet+0x6c26/0x7324 net/bluetooth/hci_event.c:5375 Read of size 6 at addr ffff88809eaa1184 by task kworker/u5:0/1190 CPU: 0 PID: 1190 Comm: kworker/u5:0 Not tainted 4.14.184-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci0 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393 memcpy include/linux/string.h:347 [inline] bacpy include/net/bluetooth/bluetooth.h:233 [inline] hci_extended_inquiry_result_evt net/bluetooth/hci_event.c:3840 [inline] hci_event_packet+0x6c26/0x7324 net/bluetooth/hci_event.c:5375 hci_rx_work+0x3da/0x950 net/bluetooth/hci_core.c:4244 process_one_work+0x7c0/0x14c0 kernel/workqueue.c:2116 worker_thread+0x5d7/0x1080 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Allocated by task 6348: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.0+0x4f/0xd0 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.isra.0+0x35/0xd0 net/core/skbuff.c:137 __alloc_skb+0xca/0x4c0 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:980 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:336 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:180 [inline] vhci_write+0xb1/0x420 drivers/bluetooth/hci_vhci.c:299 call_write_iter include/linux/fs.h:1778 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x44e/0x630 fs/read_write.c:482 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 3639: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xaf/0x190 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcb/0x260 mm/slab.c:3815 skb_free_head+0x83/0xa0 net/core/skbuff.c:554 skb_release_data+0x57e/0x7d0 net/core/skbuff.c:574 skb_release_all+0x46/0x60 net/core/skbuff.c:631 __kfree_skb net/core/skbuff.c:645 [inline] consume_skb+0xa7/0x330 net/core/skbuff.c:705 skb_free_datagram+0x16/0xe0 net/core/datagram.c:331 netlink_recvmsg+0x5ef/0xda0 net/netlink/af_netlink.c:1957 sock_recvmsg_nosec net/socket.c:819 [inline] sock_recvmsg net/socket.c:826 [inline] sock_recvmsg+0xc0/0x100 net/socket.c:822 ___sys_recvmsg+0x21f/0x4d0 net/socket.c:2221 __sys_recvmsg+0xa0/0x120 net/socket.c:2266 SYSC_recvmsg net/socket.c:2278 [inline] SyS_recvmsg+0x27/0x40 net/socket.c:2273 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff88809eaa0d80 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 4 bytes to the right of 1024-byte region [ffff88809eaa0d80, ffff88809eaa1180) The buggy address belongs to the page: page:ffffea00027aa800 count:1 mapcount:0 mapping:ffff88809eaa0000 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffff88809eaa0000 0000000000000000 0000000100000007 raw: ffffea00023e8b20 ffffea00023dd520 ffff8880aa800ac0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809eaa1080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88809eaa1100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88809eaa1180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809eaa1200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809eaa1280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================