1 files changed, 47 insertions, 8 deletions

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 75b770514067..e48792828939 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -123,8 +123,8 @@ static int logo_lines;
    enums.  */
 static int logo_shown = FBCON_LOGO_CANSHOW;
 /* console mappings */
-static int first_fb_vc;
-static int last_fb_vc = MAX_NR_CONSOLES - 1;
+static unsigned int first_fb_vc;
+static unsigned int last_fb_vc = MAX_NR_CONSOLES - 1;
 static int fbcon_is_default = 1; 
 static int primary_device = -1;
 static int fbcon_has_console_bind;
@@ -474,10 +474,12 @@ static int __init fb_console_setup(char *this_opt)
 			options += 3;
 			if (*options)
 				first_fb_vc = simple_strtoul(options, &options, 10) - 1;
-			if (first_fb_vc < 0)
+			if (first_fb_vc >= MAX_NR_CONSOLES)
 				first_fb_vc = 0;
 			if (*options++ == '-')
 				last_fb_vc = simple_strtoul(options, &options, 10) - 1;
+			if (last_fb_vc < first_fb_vc || last_fb_vc >= MAX_NR_CONSOLES)
+				last_fb_vc = MAX_NR_CONSOLES - 1;
 			fbcon_is_default = 0; 
 			continue;
 		}
@@ -602,7 +604,7 @@ static void fbcon_prepare_logo(struct vc_data *vc, struct fb_info *info,
 		if (scr_readw(r) != vc->vc_video_erase_char)
 			break;
 	if (r != q && new_rows >= rows + logo_lines) {
-		save = kmalloc(array3_size(logo_lines, new_cols, 2),
+		save = kzalloc(array3_size(logo_lines, new_cols, 2),
 			       GFP_KERNEL);
 		if (save) {
 			int i = cols < new_cols ? cols : new_cols;
@@ -2490,9 +2492,17 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font,
 	if (charcount != 256 && charcount != 512)
 		return -EINVAL;
 
+	/* font bigger than screen resolution ? */
+	if (w > FBCON_SWAP(info->var.rotate, info->var.xres, info->var.yres) ||
+	    h > FBCON_SWAP(info->var.rotate, info->var.yres, info->var.xres))
+		return -EINVAL;
+
+	if (font->width > 32 || font->height > 32)
+		return -EINVAL;
+
 	/* Make sure drawing engine can handle the font */
-	if (!(info->pixmap.blit_x & (1 << (font->width - 1))) ||
-	    !(info->pixmap.blit_y & (1 << (font->height - 1))))
+	if (!(info->pixmap.blit_x & BIT(font->width - 1)) ||
+	    !(info->pixmap.blit_y & BIT(font->height - 1)))
 		return -EINVAL;
 
 	/* Make sure driver can handle the font length */
@@ -2756,6 +2766,34 @@ void fbcon_update_vcs(struct fb_info *info, bool all)
 }
 EXPORT_SYMBOL(fbcon_update_vcs);
 
+/* let fbcon check if it supports a new screen resolution */
+int fbcon_modechange_possible(struct fb_info *info, struct fb_var_screeninfo *var)
+{
+	struct fbcon_ops *ops = info->fbcon_par;
+	struct vc_data *vc;
+	unsigned int i;
+
+	WARN_CONSOLE_UNLOCKED();
+
+	if (!ops)
+		return 0;
+
+	/* prevent setting a screen size which is smaller than font size */
+	for (i = first_fb_vc; i <= last_fb_vc; i++) {
+		vc = vc_cons[i].d;
+		if (!vc || vc->vc_mode != KD_TEXT ||
+			   registered_fb[con2fb_map[i]] != info)
+			continue;
+
+		if (vc->vc_font.width  > FBCON_SWAP(var->rotate, var->xres, var->yres) ||
+		    vc->vc_font.height > FBCON_SWAP(var->rotate, var->yres, var->xres))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fbcon_modechange_possible);
+
 int fbcon_mode_deleted(struct fb_info *info,
 		       struct fb_videomode *mode)
 {
@@ -3286,6 +3324,9 @@ static void fbcon_register_existing_fbs(struct work_struct *work)
 
 	console_lock();
 
+	deferred_takeover = false;
+	logo_shown = FBCON_LOGO_DONTSHOW;
+
 	for_each_registered_fb(i)
 		fbcon_fb_registered(registered_fb[i]);
 
@@ -3303,8 +3344,6 @@ static int fbcon_output_notifier(struct notifier_block *nb,
 	pr_info("fbcon: Taking over console\n");
 
 	dummycon_unregister_output_notifier(&fbcon_output_nb);
-	deferred_takeover = false;
-	logo_shown = FBCON_LOGO_DONTSHOW;
 
 	/* We may get called in atomic context */
 	schedule_work(&fbcon_deferred_takeover_work);