From: Justus Winter <4winter@informatik.uni-hamburg.de>
To: notmuch@notmuchmail.org
Subject: [PATCH 6/6] Avoid potentially dereferencing a NULL pointer
Date: Mon, 24 Sep 2012 17:21:20 +0200
Message-Id:
 <1348500080-29726-6-git-send-email-4winter@informatik.uni-hamburg.de>
In-Reply-To:
 <1348500080-29726-1-git-send-email-4winter@informatik.uni-hamburg.de>
References: <873927eb5i.fsf@convex-new.cs.unb.ca>
	<1348500080-29726-1-git-send-email-4winter@informatik.uni-hamburg.de>
Precedence: list

GMIME_IS_MULTIPART and GMIME_IS_MESSAGE both handle NULL pointers
gracefully, but the G_OBJECT_TYPE used in the error handling block
dereferences it without checking it first.

Fix this by checking whether parent->part is valid.

Found using the clang static analyzer.

Signed-off-by: Justus Winter <4winter@informatik.uni-hamburg.de>
---
 mime-node.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mime-node.c b/mime-node.c
index 97e8b48..839737a 100644
--- a/mime-node.c
+++ b/mime-node.c
@@ -291,7 +291,7 @@ mime_node_child (mime_node_t *parent, int child)
     GMimeObject *sub;
     mime_node_t *node;
 
-    if (!parent || child < 0 || child >= parent->nchildren)
+    if (!parent || !parent->part || child < 0 || child >= parent->nchildren)
 	return NULL;
 
     if (GMIME_IS_MULTIPART (parent->part)) {
-- 
1.7.10.4