audit: type=1804 audit(1593332748.235:347): pid=31743 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir924344172/syzkaller.RCItHh/1561/bus" dev="sda1" ino=16897 res=1
audit: type=1804 audit(1593332748.285:348): pid=31744 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir924344172/syzkaller.RCItHh/1561/bus" dev="sda1" ino=16897 res=1
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:347 [inline]
BUG: KASAN: slab-out-of-bounds in soft_cursor+0x445/0xa40 drivers/video/fbdev/core/softcursor.c:70
Read of size 9 at addr ffff8880a1a843b0 by task syz-executor.3/31738

CPU: 1 PID: 31738 Comm: syz-executor.3 Not tainted 4.14.184-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+0x1b2/0x283 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+0x20/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:347 [inline]
 soft_cursor+0x445/0xa40 drivers/video/fbdev/core/softcursor.c:70
 bit_cursor+0x1072/0x1660 drivers/video/fbdev/core/bitblit.c:386
 fbcon_cursor+0x4b1/0x690 drivers/video/fbdev/core/fbcon.c:1350
 hide_cursor+0x7a/0x2a0 drivers/tty/vt/vt.c:590
 redraw_screen+0x2a2/0x760 drivers/tty/vt/vt.c:680
 vc_do_resize+0xbe0/0xde0 drivers/tty/vt/vt.c:967
 vt_ioctl+0x1a64/0x1f20 drivers/tty/vt/vt_ioctl.c:901
 tty_ioctl+0x6c9/0x1220 drivers/tty/tty_io.c:2661
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45cb19
RSP: 002b:00007f9d88f32c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004f35c0 RCX: 000000000045cb19
RDX: 0000000020000000 RSI: 000000000000560a RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000067f R14: 00000000004c9859 R15: 00007f9d88f336d4

Allocated by task 23176:
 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 mm/slab.c:3720 [inline]
 __kmalloc+0x15a/0x400 mm/slab.c:3729
 kmalloc include/linux/slab.h:493 [inline]
 fbcon_set_font+0x2f8/0x7c0 drivers/video/fbdev/core/fbcon.c:2621
 con_font_set drivers/tty/vt/vt.c:4182 [inline]
 con_font_op+0xb73/0xf70 drivers/tty/vt/vt.c:4247
 vt_ioctl+0x736/0x1f20 drivers/tty/vt/vt_ioctl.c:928
 tty_ioctl+0x6c9/0x1220 drivers/tty/tty_io.c:2661
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 20761:
 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]
 kfree_skb+0xae/0x340 net/core/skbuff.c:663
 vti6_tnl_xmit+0x2a7/0x1860 net/ipv6/ip6_vti.c:597
 __netdev_start_xmit include/linux/netdevice.h:4039 [inline]
 netdev_start_xmit include/linux/netdevice.h:4048 [inline]
 xmit_one net/core/dev.c:3009 [inline]
 dev_hard_start_xmit+0x186/0x880 net/core/dev.c:3025
 __dev_queue_xmit+0x1dce/0x25a0 net/core/dev.c:3525
 packet_snd.isra.0+0x119b/0x2170 net/packet/af_packet.c:3012
 packet_sendmsg+0x101c/0x2420 net/packet/af_packet.c:3037
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:656
 ___sys_sendmsg+0x349/0x840 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

The buggy address belongs to the object at ffff8880a1a84280
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 304 bytes inside of
 512-byte region [ffff8880a1a84280, ffff8880a1a84480)
The buggy address belongs to the page:
page:ffffea000286a100 count:1 mapcount:0 mapping:ffff8880a1a84000 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff8880a1a84000 0000000000000000 0000000100000006
raw: ffffea0002953ee0 ffffea000223ada0 ffff8880aa800940 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a1a84280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a1a84300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880a1a84380: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                     ^
 ffff8880a1a84400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a1a84480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================