From df8c6c3ad758fbcd88fbbe7fb53221a32ae3abe2 Mon Sep 17 00:00:00 2001
From: Vincent Sanders <vince@kyllikki.org>
Date: Mon, 10 Nov 2014 15:05:56 +0000
Subject: Avoid calling calloc with 0 length data.

CERT MEM04-C suggests that zero length allocations behaviour might be
surprising so it should be avoided. This adds a check to ensure a zero
length allocation will be avoided. Additionally it returns errors to
the caller rather than warning directly (in some error paths)
---
 desktop/frames.c | 40 +++++++++++++++++++++++++---------------
 desktop/frames.h |  9 ++++++++-
 2 files changed, 33 insertions(+), 16 deletions(-)

(limited to 'desktop')

diff --git a/desktop/frames.c b/desktop/frames.c
index 3e5556f5c..934217761 100644
--- a/desktop/frames.c
+++ b/desktop/frames.c
@@ -180,14 +180,8 @@ void browser_window_handle_scrollbars(struct browser_window *bw)
 }
 
 
-/**
- * Create and open a iframes for a browser window.
- *
- * \param  bw	    The browser window to create iframes for
- * \param  iframe   The iframes to create
- */
-
-void browser_window_create_iframes(struct browser_window *bw,
+/* exported function documented in desktop/frames.h */
+nserror browser_window_create_iframes(struct browser_window *bw,
 		struct content_html_iframe *iframe)
 {
 	struct browser_window *window;
@@ -195,12 +189,22 @@ void browser_window_create_iframes(struct browser_window *bw,
 	struct rect rect;
 	int iframes = 0;
 	int index;
+	nserror ret = NSERROR_OK;
 
-	for (cur = iframe; cur; cur = cur->next)
+	if (iframe == NULL) {
+		return NSERROR_BAD_PARAMETER;
+	}
+
+	/* Count iframe list and allocate enough space within the
+	 * browser window.
+	 */
+	for (cur = iframe; cur; cur = cur->next) {
 		iframes++;
+	}
 	bw->iframes = calloc(iframes, sizeof(*bw));
-	if (!bw->iframes)
-		return;
+	if (!bw->iframes) {
+		return NSERROR_NOMEM;
+	}
 	bw->iframe_count = iframes;
 
 	index = 0;
@@ -220,10 +224,14 @@ void browser_window_create_iframes(struct browser_window *bw,
 		window->margin_width = cur->margin_width;
 		window->margin_height = cur->margin_height;
 		window->scale = bw->scale;
-		if (cur->name) {
+		if (cur->name != NULL) {
 			window->name = strdup(cur->name);
-			if (!window->name)
-				warn_user("NoMemory", 0);
+			if (window->name == NULL) {
+				free(bw->iframes) ;
+				bw->iframes = 0;
+				bw->iframe_count = 0;
+				return NSERROR_NOMEM;
+			}
 		}
 
 		/* linking */
@@ -248,7 +256,7 @@ void browser_window_create_iframes(struct browser_window *bw,
 		window = &(bw->iframes[index++]);
 		if (cur->url) {
 			/* fetch iframe's content */
-			browser_window_navigate(window, 
+			ret = browser_window_navigate(window,
 				cur->url,
 				hlcache_handle_get_url(bw->current_content),
 				BW_NAVIGATE_UNVERIFIABLE,
@@ -257,6 +265,8 @@ void browser_window_create_iframes(struct browser_window *bw,
 				bw->current_content);
 		}
 	}
+
+	return ret;
 }
 
 
diff --git a/desktop/frames.h b/desktop/frames.h
index 15efb7d67..bca7f2e68 100644
--- a/desktop/frames.h
+++ b/desktop/frames.h
@@ -25,7 +25,14 @@
 
 struct scrollbar_msg_data;
 
-void browser_window_create_iframes(struct browser_window *bw,
+/**
+ * Create and open iframes for a browser window.
+ *
+ * \param bw	  The browser window to create iframes for.
+ * \param iframe  The iframes to create from.
+ * \param NSERROR_OK or error code on faliure.
+ */
+nserror browser_window_create_iframes(struct browser_window *bw,
 		struct content_html_iframe *iframe);
 void browser_window_recalculate_iframes(struct browser_window *bw);
 void browser_window_create_frameset(struct browser_window *bw,
-- 
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