From: Thomas Hindoe Paaboel Andersen <phomes@gmail.com>
Date: Wed, 18 Jun 2014 21:35:01 +0000 (+0200)
Subject: bootchart: add assert
X-Git-Tag: v215~334
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=8271bd16ce9327834d8580e55bb5e4e0896fd98a

bootchart: add assert

since 376cd3b89c62f580a6f576cecfbbb28d3944118f LIST_FIND_TAIL accepts
an empty list. That removed an assert in LIST_FIND_TAIL and we now
theoretically risk a null pointer deref. This adds the assert directly
to protect against that.
---

diff --git a/src/bootchart/svg.c b/src/bootchart/svg.c
index 812119952..bf6636cab 100644
--- a/src/bootchart/svg.c
+++ b/src/bootchart/svg.c
@@ -80,6 +80,8 @@ static void svg_header(void) {
         double h;
         struct list_sample_data *sampledata_last;
 
+        assert(head);
+
         sampledata = head;
         LIST_FIND_TAIL(link, sampledata, head);
         sampledata_last = head;