==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:348 [inline]
BUG: KASAN: slab-out-of-bounds in soft_cursor+0x439/0xa30 drivers/video/fbdev/core/softcursor.c:70
Read of size 10 at addr ffff88800d3a1710 by task syz-executor.3/18427

CPU: 0 PID: 18427 Comm: syz-executor.3 Not tainted 4.19.91-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x123/0x190 mm/kasan/kasan.c:267
 memcpy+0x24/0x50 mm/kasan/kasan.c:302
 memcpy include/linux/string.h:348 [inline]
 soft_cursor+0x439/0xa30 drivers/video/fbdev/core/softcursor.c:70
 bit_cursor+0x12fc/0x1a60 drivers/video/fbdev/core/bitblit.c:386
 fbcon_cursor+0x58a/0x7b0 drivers/video/fbdev/core/fbcon.c:1369
 hide_cursor+0x9e/0x300 drivers/tty/vt/vt.c:895
 redraw_screen+0x2ee/0x8e0 drivers/tty/vt/vt.c:988
 fbcon_do_set_font+0x73a/0xa40 drivers/video/fbdev/core/fbcon.c:2583
 fbcon_copy_font+0x12c/0x190 drivers/video/fbdev/core/fbcon.c:2598
 con_font_copy drivers/tty/vt/vt.c:4548 [inline]
 con_font_op+0x69a/0x1250 drivers/tty/vt/vt.c:4563
 vt_ioctl+0x1784/0x2530 drivers/tty/vt/vt_ioctl.c:965
 tty_ioctl+0x7f3/0x1510 drivers/tty/tty_io.c:2669
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a919
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb5f5a7dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919
RDX: 0000000020000440 RSI: 0000000000004b72 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb5f5a7e6d4
R13: 00000000004c3a7b R14: 00000000004d9060 R15: 00000000ffffffff

Allocated by task 21324:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc mm/kasan/kasan.c:553 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc+0x15d/0x750 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 fbcon_set_font+0x32d/0x860 drivers/video/fbdev/core/fbcon.c:2641
 con_font_set drivers/tty/vt/vt.c:4492 [inline]
 con_font_op+0xe18/0x1250 drivers/tty/vt/vt.c:4557
 vt_ioctl+0xd2e/0x2530 drivers/tty/vt/vt_ioctl.c:913
 tty_ioctl+0x7f3/0x1510 drivers/tty/tty_io.c:2669
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 17924:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcf/0x220 mm/slab.c:3822
 skb_free_head+0x99/0xc0 net/core/skbuff.c:554
 skb_release_data+0x619/0x8d0 net/core/skbuff.c:574
 skb_release_all+0x4d/0x60 net/core/skbuff.c:631
 __kfree_skb net/core/skbuff.c:645 [inline]
 consume_skb net/core/skbuff.c:705 [inline]
 consume_skb+0xe2/0x390 net/core/skbuff.c:699
 netlink_broadcast_filtered+0x316/0xb30 net/netlink/af_netlink.c:1519
 netlink_broadcast+0x3a/0x50 net/netlink/af_netlink.c:1541
 uevent_net_broadcast_tagged lib/kobject_uevent.c:370 [inline]
 kobject_uevent_net_broadcast lib/kobject_uevent.c:409 [inline]
 kobject_uevent_env+0xcbf/0x101f lib/kobject_uevent.c:590
 kobject_uevent+0x20/0x26 lib/kobject_uevent.c:639
 kobject_cleanup lib/kobject.c:649 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put.cold+0x177/0x2e6 lib/kobject.c:708
 netdev_queue_update_kobjects+0x250/0x3d0 net/core/net-sysfs.c:1515
 remove_queue_kobjects net/core/net-sysfs.c:1568 [inline]
 netdev_unregister_kobject+0x162/0x1f0 net/core/net-sysfs.c:1718
 rollback_registered_many+0x6bb/0xda0 net/core/dev.c:8044
 unregister_netdevice_many.part.0+0x1b/0x1f0 net/core/dev.c:9130
 unregister_netdevice_many+0x3b/0x50 net/core/dev.c:9129
 rtnl_delete_link+0xda/0x130 net/core/rtnetlink.c:2760
 rtnl_dellink+0x3a7/0x920 net/core/rtnetlink.c:2814
 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:4768
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4786
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x53a/0x730 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88800d3a15c0
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 336 bytes inside of
 512-byte region [ffff88800d3a15c0, ffff88800d3a17c0)
The buggy address belongs to the page:
page:ffffea000034e840 count:1 mapcount:0 mapping:ffff88812c31c940 index:0xffff88800d3a1d40
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffffea00015fae88 ffffea00022b2388 ffff88812c31c940
raw: ffff88800d3a1d40 ffff88800d3a10c0 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88800d3a1600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88800d3a1680: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
>ffff88800d3a1700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff88800d3a1780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88800d3a1800: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================
kobject: 'loop1' (00000000d4086adb): kobject_uevent_env
kobject: 'loop1' (00000000d4086adb): fill_kobj_path: path = '/devices/virtual/block/loop1'