1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index cd1407921af..354711c84aa 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c
@@ -773,6 +773,29 @@ fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var)
         return 0;
 }
 
+static int fb_check_caps(struct fb_info *info, struct fb_var_screeninfo *var,
+			 u32 activate)
+{
+	struct fb_event event;
+	struct fb_blit_caps caps, fbcaps;
+	int err = 0;
+
+	memset(&caps, 0, sizeof(caps));
+	memset(&fbcaps, 0, sizeof(fbcaps));
+	caps.flags = (activate & FB_ACTIVATE_ALL) ? 1 : 0;
+	event.info = info;
+	event.data = ∩︀
+	fb_notifier_call_chain(FB_EVENT_GET_REQ, &event);
+	info->fbops->fb_get_caps(info, &fbcaps, var);
+
+	if (((fbcaps.x ^ caps.x) & caps.x) ||
+	    ((fbcaps.y ^ caps.y) & caps.y) ||
+	    (fbcaps.len < caps.len))
+		err = -EINVAL;
+
+	return err;
+}
+
 int
 fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
 {
@@ -817,7 +840,15 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
 			struct fb_videomode mode;
 			int err = 0;
 
+			if (info->fbops->fb_get_caps) {
+				err = fb_check_caps(info, var, activate);
+
+				if (err)
+					goto done;
+			}
+
 			info->var = *var;
+
 			if (info->fbops->fb_set_par)
 				info->fbops->fb_set_par(info);
 
@@ -843,6 +874,8 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
 			}
 		}
 	}
+
+ done:
 	return 0;
 }