1 files changed, 19 insertions, 9 deletions

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 64458982be40..fd27f1978635 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -641,19 +641,27 @@ static void drm_fb_helper_damage(struct drm_fb_helper *helper, u32 x, u32 y,
 static void drm_fb_helper_memory_range_to_clip(struct fb_info *info, off_t off, size_t len,
 					       struct drm_rect *clip)
 {
+	u32 line_length = info->fix.line_length;
+	u32 fb_height = info->var.yres;
 	off_t end = off + len;
 	u32 x1 = 0;
-	u32 y1 = off / info->fix.line_length;
+	u32 y1 = off / line_length;
 	u32 x2 = info->var.xres;
-	u32 y2 = DIV_ROUND_UP(end, info->fix.line_length);
+	u32 y2 = DIV_ROUND_UP(end, line_length);
+
+	/* Don't allow any of them beyond the bottom bound of display area */
+	if (y1 > fb_height)
+		y1 = fb_height;
+	if (y2 > fb_height)
+		y2 = fb_height;
 
 	if ((y2 - y1) == 1) {
 		/*
 		 * We've only written to a single scanline. Try to reduce
 		 * the number of horizontal pixels that need an update.
 		 */
-		off_t bit_off = (off % info->fix.line_length) * 8;
-		off_t bit_end = (end % info->fix.line_length) * 8;
+		off_t bit_off = (off % line_length) * 8;
+		off_t bit_end = (end % line_length) * 8;
 
 		x1 = bit_off / info->var.bits_per_pixel;
 		x2 = DIV_ROUND_UP(bit_end, info->var.bits_per_pixel);
@@ -1537,17 +1545,19 @@ static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var,
 	}
 }
 
-static void __fill_var(struct fb_var_screeninfo *var,
+static void __fill_var(struct fb_var_screeninfo *var, struct fb_info *info,
 		       struct drm_framebuffer *fb)
 {
 	int i;
 
 	var->xres_virtual = fb->width;
 	var->yres_virtual = fb->height;
-	var->accel_flags = FB_ACCELF_TEXT;
+	var->accel_flags = 0;
 	var->bits_per_pixel = drm_format_info_bpp(fb->format, 0);
 
-	var->height = var->width = 0;
+	var->height = info->var.height;
+	var->width = info->var.width;
+
 	var->left_margin = var->right_margin = 0;
 	var->upper_margin = var->lower_margin = 0;
 	var->hsync_len = var->vsync_len = 0;
@@ -1610,7 +1620,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 		return -EINVAL;
 	}
 
-	__fill_var(var, fb);
+	__fill_var(var, info, fb);
 
 	/*
 	 * fb_pan_display() validates this, but fb_set_par() doesn't and just
@@ -2066,7 +2076,7 @@ static void drm_fb_helper_fill_var(struct fb_info *info,
 	info->pseudo_palette = fb_helper->pseudo_palette;
 	info->var.xoffset = 0;
 	info->var.yoffset = 0;
-	__fill_var(&info->var, fb);
+	__fill_var(&info->var, info, fb);
 	info->var.activate = FB_ACTIVATE_NOW;
 
 	drm_fb_helper_fill_pixel_fmt(&info->var, format);