fbmem: don't allow too huge resolutions

[linux-2.6-microblaze.git] / drivers / video / fbdev / core / fbmem.c

diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 71fb710..7420d2c 100644 (file)
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -962,6 +962,7 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
        struct fb_var_screeninfo old_var;
        struct fb_videomode mode;
        struct fb_event event;
+       u32 unused;
 
        if (var->activate & FB_ACTIVATE_INV_MODE) {
                struct fb_videomode mode1, mode2;
@@ -1008,6 +1009,11 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
        if (var->xres < 8 || var->yres < 8)
                return -EINVAL;
 
+       /* Too huge resolution causes multiplication overflow. */
+       if (check_mul_overflow(var->xres, var->yres, &unused) ||
+           check_mul_overflow(var->xres_virtual, var->yres_virtual, &unused))
+               return -EINVAL;
+
        ret = info->fbops->fb_check_var(var, info);
 
        if (ret)