[PATCH] con_font_default sanitized

->con_font_default() sanitized.  We copy font name (if any) from userland
in the caller and pass it explicitly.  We are also beginning to get rid
of console_font_op in method arguments.
Signed-off-by: Al Viro <viro@parcelfarce.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/char/vt.c

@@ -100,6 +100,7 @@
 #include <linux/workqueue.h>
 #include <linux/bootmem.h>
 #include <linux/pm.h>
+#include <linux/font.h>
 
 #include <asm/io.h>
 #include <asm/system.h>
@@ -3139,17 +3140,31 @@ int con_font_set(int currcons, struct console_font_op *op)
 
 int con_font_default(int currcons, struct console_font_op *op)
 {
+	struct console_font font = {.width = op->width, .height = op->height};
+	char name[MAX_FONT_NAME];
+	char *s = name;
 	int rc;
 
 	if (vt_cons[currcons]->vc_mode != KD_TEXT)
 		return -EINVAL;
 
+	if (!op->data)
+		s = NULL;
+	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
+		return -EFAULT;
+	else
+		name[MAX_FONT_NAME - 1] = 0;
+
 	acquire_console_sem();
 	if (sw->con_font_default)
-		rc = sw->con_font_default(vc_cons[currcons].d, op);
+		rc = sw->con_font_default(vc_cons[currcons].d, &font, s);
 	else
 		rc = -ENOSYS;
 	release_console_sem();
+	if (!rc) {
+		op->width = font.width;
+		op->height = font.height;
+	}
 	return rc;
 }
 

drivers/video/console/fbcon.c

@@ -2272,24 +2272,21 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font_op *op)
 	return fbcon_do_set_font(vc, op, new_data, 1);
 }
 
-static int fbcon_set_def_font(struct vc_data *vc, struct console_font_op *op)
+static int fbcon_set_def_font(struct vc_data *vc, struct console_font *font, char *name)
 {
 	struct fb_info *info = registered_fb[(int) con2fb_map[vc->vc_num]];
-	char name[MAX_FONT_NAME];
 	struct font_desc *f;
+	struct console_font_op crap;
 
-	if (!op->data)
+	if (!name)
 		f = get_default_font(info->var.xres, info->var.yres);
-	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
-		return -EFAULT;
-	else {
-		name[MAX_FONT_NAME - 1] = 0;
-		if (!(f = find_font(name)))
+	else if (!(f = find_font(name)))
 		return -ENOENT;
-	}
-	op->width = f->width;
-	op->height = f->height;
-	return fbcon_do_set_font(vc, op, f->data, 0);
+
+	crap.op = KD_FONT_OP_SET_DEFAULT;
+	crap.width = font->width = f->width;
+	crap.height = font->height = f->height;
+	return fbcon_do_set_font(vc, &crap, f->data, 0);
 }
 
 static u16 palette_red[16];

drivers/video/console/newport_con.c

@@ -52,7 +52,7 @@ static int xcurs_correction = 29;
 static int newport_xsize;
 static int newport_ysize;
 
-static int newport_set_def_font(int unit, struct console_font_op *op);
+static int newport_set_def_font(int unit, struct console_font *op);
 
 #define BMASK(c) (c << 24)
 
@@ -531,7 +531,7 @@ static int newport_set_font(int unit, struct console_font_op *op)
 	return 0;
 }
 
-static int newport_set_def_font(int unit, struct console_font_op *op)
+static int newport_set_def_font(int unit, struct console_font *op)
 {
 	if (font_data[unit] != FONT_DATA) {
 		if (--REFCOUNT(font_data[unit]) == 0)
@@ -543,7 +543,7 @@ static int newport_set_def_font(int unit, struct console_font_op *op)
 	return 0;
 }
 
-static int newport_font_default(struct vc_data *vc, struct console_font_op *op)
+static int newport_font_default(struct vc_data *vc, struct console_font *op, char *name)
 {
 	return newport_set_def_font(vc->vc_num, op);
 }

include/linux/console.h

@@ -19,6 +19,7 @@
 
 struct vc_data;
 struct console_font_op;
+struct console_font;
 struct module;
 
 /*
@@ -42,7 +43,7 @@ struct consw {
 	int	(*con_blank)(struct vc_data *, int, int);
 	int	(*con_font_set)(struct vc_data *, struct console_font_op *);
 	int	(*con_font_get)(struct vc_data *, struct console_font_op *);
-	int	(*con_font_default)(struct vc_data *, struct console_font_op *);
+	int	(*con_font_default)(struct vc_data *, struct console_font *, char *);
 	int	(*con_font_copy)(struct vc_data *, struct console_font_op *);
 	int	(*con_resize)(struct vc_data *, unsigned int, unsigned int);
 	int	(*con_set_palette)(struct vc_data *, unsigned char *);

include/linux/kd.h

@@ -152,6 +152,12 @@ struct console_font_op {
 	unsigned char *data;	/* font data with height fixed to 32 */
 };
 
+struct console_font {
+	unsigned int width, height;	/* font size */
+	unsigned int charcount;
+	unsigned char *data;	/* font data with height fixed to 32 */
+};
+
 #define KD_FONT_OP_SET		0	/* Set font */
 #define KD_FONT_OP_GET		1	/* Get font */
 #define KD_FONT_OP_SET_DEFAULT	2	/* Set font to default, data points to name / NULL */