fbdev: avoid vertical overflow when making space for the logo

fbcon_prepare_logo(): Avoid vertical overflow when making space for the logo

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-By: James Simmons <jsimmons@infradead.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 2 deletions

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 0429fd2cece0..bd131d472e24 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -618,8 +618,13 @@ static void fbcon_prepare_logo(struct vc_data *vc, struct fb_info *info,
                         r -= cols;
                 }
                 if (!save) {
-                        vc->vc_y += logo_lines;
-                        vc->vc_pos += logo_lines * vc->vc_size_row;
+                        int lines;
+                        if (vc->vc_y + logo_lines >= rows)
+                                lines = rows - vc->vc_y - 1;
+                        else
+                                lines = logo_lines;
+                        vc->vc_y += lines;
+                        vc->vc_pos += lines * vc->vc_size_row;
                 }
         }
         scr_memsetw((unsigned short *) vc->vc_origin,