diff options
Diffstat (limited to 'drivers/video/fbdev/core/fbcon.c')
| -rw-r--r-- | drivers/video/fbdev/core/fbcon.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index 8a31fc2b2258..66167830fefd 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -2191,6 +2191,9 @@ static void updatescrollmode(struct fbcon_display *p, } } +#define PITCH(w) (((w) + 7) >> 3) +#define CALC_FONTSZ(h, p, c) ((h) * (p) * (c)) /* size = height * pitch * charcount */ + static int fbcon_resize(struct vc_data *vc, unsigned int width, unsigned int height, unsigned int user) { @@ -2200,6 +2203,24 @@ static int fbcon_resize(struct vc_data *vc, unsigned int width, struct fb_var_screeninfo var = info->var; int x_diff, y_diff, virt_w, virt_h, virt_fw, virt_fh; + if (ops->p && ops->p->userfont && FNTSIZE(vc->vc_font.data)) { + int size; + int pitch = PITCH(vc->vc_font.width); + + /* + * If user font, ensure that a possible change to user font + * height or width will not allow a font data out-of-bounds access. + * NOTE: must use original charcount in calculation as font + * charcount can change and cannot be used to determine the + * font data allocated size. + */ + if (pitch <= 0) + return -EINVAL; + size = CALC_FONTSZ(vc->vc_font.height, pitch, FNTCHARCNT(vc->vc_font.data)); + if (size > FNTSIZE(vc->vc_font.data)) + return -EINVAL; + } + virt_w = FBCON_SWAP(ops->rotate, width, height); virt_h = FBCON_SWAP(ops->rotate, height, width); virt_fw = FBCON_SWAP(ops->rotate, vc->vc_font.width, @@ -2652,7 +2673,7 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, int size; int i, csum; u8 *new_data, *data = font->data; - int pitch = (font->width+7) >> 3; + int pitch = PITCH(font->width); /* Is there a reason why fbconsole couldn't handle any charcount >256? * If not this check should be changed to charcount < 256 */ @@ -2668,7 +2689,7 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, if (fbcon_invalid_charcount(info, charcount)) return -EINVAL; - size = h * pitch * charcount; + size = CALC_FONTSZ(h, pitch, charcount); new_data = kmalloc(FONT_EXTRA_WORDS * sizeof(int) + size, GFP_USER); |