==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:347 [inline]
BUG: KASAN: slab-out-of-bounds in fbcon_get_font+0x262/0x530 drivers/video/fbdev/core/fbcon.c:2424
Read of size 3 at addr ffff88805b9fd0cf by task syz-executor.0/17107

CPU: 1 PID: 17107 Comm: syz-executor.0 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]
 fbcon_get_font+0x262/0x530 drivers/video/fbdev/core/fbcon.c:2424
 con_font_get drivers/tty/vt/vt.c:4098 [inline]
 con_font_op+0x1c6/0xf70 drivers/tty/vt/vt.c:4249
 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
RIP: 0033:0x45cb29
RSP: 002b:00007fb4152d9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004e6560 RCX: 000000000045cb29
RDX: 0000000020000100 RSI: 0000000000004b60 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000033b R14: 00000000004c5d23 R15: 00007fb4152da6d4

Allocated by task 13331:
 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
 do_fontx_ioctl drivers/tty/vt/vt_ioctl.c:265 [inline]
 vt_ioctl+0x2b8/0x1f20 drivers/tty/vt/vt_ioctl.c:945
 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 6352:
 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
 kvfree+0x45/0x50 mm/util.c:416
 __do_replace+0x3f6/0x580 net/ipv6/netfilter/ip6_tables.c:1107
 do_replace net/ipv6/netfilter/ip6_tables.c:1161 [inline]
 do_ip6t_set_ctl+0x255/0x3a3 net/ipv6/netfilter/ip6_tables.c:1685
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x5f/0xb0 net/netfilter/nf_sockopt.c:115
 ipv6_setsockopt net/ipv6/ipv6_sockglue.c:935 [inline]
 ipv6_setsockopt+0xfd/0x130 net/ipv6/ipv6_sockglue.c:919
 tcp_setsockopt net/ipv4/tcp.c:2828 [inline]
 tcp_setsockopt+0x7b/0xc0 net/ipv4/tcp.c:2822
 SYSC_setsockopt net/socket.c:1865 [inline]
 SyS_setsockopt+0x110/0x1e0 net/socket.c:1844
 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 ffff88805b9fccc0
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 1039 bytes inside of
 2048-byte region [ffff88805b9fccc0, ffff88805b9fd4c0)
The buggy address belongs to the page:
page:ffffea00016e7f00 count:1 mapcount:0 mapping:ffff88805b9fc440 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffff88805b9fc440 0000000000000000 0000000100000003
raw: ffffea00016f7ca0 ffffea00016e8b20 ffff8880aa800c40 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88805b9fcf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805b9fd000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805b9fd080: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
                                                 ^
 ffff88805b9fd100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805b9fd180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================