general protection fault in fbcon_set_font

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3242aa3a Linux 4.14.222
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10100abcd00000
kernel config: https://syzkaller.appspot.com/x/.config?x=d6fee509440d713f
dashboard link: https://syzkaller.appspot.com/bug?extid=9dc20ecc28765551d480

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9dc20e...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 24536 Comm: syz-executor.3 Not tainted 4.14.222-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88804ad08180 task.stack: ffff88809bd08000
RIP: 0010:fbcon_set_font+0x590/0x7c0 drivers/video/fbdev/core/fbcon.c:2482
RSP: 0018:ffff88809bd0f9c0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 000000000000001b RCX: ffffc9000b7bd000
RDX: 0000000000000076 RSI: ffffffff833601b9 RDI: 00000000000003b0
RBP: dffffc0000000000 R08: 0000000000000000 R09: 00000000c2074386
R10: ffffffff87cd2dc0 R11: 0000000000000000 R12: ffffffff8c8b0d80
R13: 00000000c37f2340 R14: 000000000000001b R15: ffff8880426921d0
FS: 00007f13e0e76700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000050e430 CR3: 0000000053090000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
con_font_set drivers/tty/vt/vt.c:4190 [inline]
con_font_op+0x9e8/0xdb0 drivers/tty/vt/vt.c:4234
vt_ioctl+0xd5d/0x1d50 drivers/tty/vt/vt_ioctl.c:938
tty_ioctl+0x50f/0x13c0 drivers/tty/tty_io.c:2661
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x75a/0xff0 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: 0033:0x465ef9
RSP: 002b:00007f13e0e76188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9
RDX: 00000000200007c0 RSI: 0000000000004b61 RDI: 0000000000000006
RBP: 00000000004bcd1c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffcde192b3f R14: 00007f13e0e76300 R15: 0000000000022000
Code: 48 89 f8 48 c1 e8 03 80 3c 28 00 0f 85 3a 02 00 00 4b 8d 04 f6 48 8b 04 c5 c0 a9 8b 8c 48 8d b8 b0 03 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 2a 84 d2 74 09 80 fa 03 0f 8e 48 01 00 00 8b 4c 24 2c
RIP: fbcon_set_font+0x590/0x7c0 drivers/video/fbdev/core/fbcon.c:2482 RSP: ffff88809bd0f9c0
---[ end trace 335a2074b6abb16c ]---


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.