syzbot

BUG: unable to handle kernel paging request at ffff888001000040
IP: writeb arch/x86/include/asm/io.h:65 [inline]
IP: vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1177 [inline]
IP: vga16fb_imageblit+0xb68/0x2140 drivers/video/fbdev/vga16fb.c:1261
PGD c9cc067 P4D c9cc067 PUD c9cd067 PMD 80000000010001e1 
Oops: 0003 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 26871 Comm: syz-executor.5 Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88804ff72640 task.stack: ffff88823a450000
RIP: 0010:writeb arch/x86/include/asm/io.h:65 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1177 [inline]
RIP: 0010:vga16fb_imageblit+0xb68/0x2140 drivers/video/fbdev/vga16fb.c:1261
RSP: 0018:ffff88823a4575b0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888001000042 RCX: 0000000000000000
RDX: ffff888001000040 RSI: ffffffff833c9ee7 RDI: ffff8880b0b692e8
RBP: dffffc0000000000 R08: 0000000000001899 R09: 0000000000000020
R10: 0000000000000002 R11: 0000000000000000 R12: ffff8880b0b692e9
R13: ffff88823a457748 R14: ffff888001000041 R15: ffff888001000040
FS:  00007f814def0700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff888001000040 CR3: 00000000a1cfd000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline]
 bit_putcs+0x81e/0xc30 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x2fe/0x480 drivers/video/fbdev/core/fbcon.c:1247
 do_update_region+0x34b/0x5b0 drivers/tty/vt/vt.c:373
 do_con_trol+0xc55/0x51e0 drivers/tty/vt/vt.c:2125
 do_con_write+0x9fb/0x19b0 drivers/tty/vt/vt.c:2454
 con_write+0x21/0xa0 drivers/tty/vt/vt.c:2805
 process_output_block drivers/tty/n_tty.c:595 [inline]
 n_tty_write+0x352/0xda0 drivers/tty/n_tty.c:2333
 do_tty_write drivers/tty/tty_io.c:959 [inline]
 tty_write+0x410/0x740 drivers/tty/tty_io.c:1043
 __vfs_write+0xe4/0x630 fs/read_write.c:480
 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
RIP: 0033:0x4665f9
RSP: 002b:00007f814def0188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000004
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffff8443bff R14: 00007f814def0300 R15: 0000000000022000
Code: 49 83 c4 01 48 89 f8 48 89 f9 49 83 c6 01 48 c1 e8 03 83 e1 07 0f b6 04 28 38 c8 7f 08 84 c0 0f 85 0f 0f 00 00 41 0f b6 44 24 ff <88> 02 49 39 de 75 c3 48 8b 74 24 18 48 01 74 24 08 e8 42 86 18 
RIP: writeb arch/x86/include/asm/io.h:65 [inline] RSP: ffff88823a4575b0
RIP: vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1177 [inline] RSP: ffff88823a4575b0
RIP: vga16fb_imageblit+0xb68/0x2140 drivers/video/fbdev/vga16fb.c:1261 RSP: ffff88823a4575b0
CR2: ffff888001000040
---[ end trace e31e54ffc42b59bc ]---