trace-graph: Fix trace_seq free-before-use

Commit e892161f731e958980fa977e2d7980f3cf0819ce changed trace_seq to
dynamically expand its buffer.  In two instances the destroy function
was called too early, causing a freed s.buffer to be used.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
LKML-Reference: <1283684704-5650-1-git-send-email-stefanha@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/trace-graph.c b/trace-graph.c
index 44c1273..4e91fe8 100644
--- a/trace-graph.c
+++ b/trace-graph.c
@@ -1666,14 +1666,17 @@ static gint draw_event_label(struct graph_info *ginfo, gint i,
          */
         ret = trace_graph_plot_display_last_event(ginfo, plot, &s,
                                                   convert_x_to_time(ginfo, p2-1));
-        trace_seq_destroy(&s);
-        if (!ret)
+        if (!ret) {
+                trace_seq_destroy(&s);
                 return p2;
+        }
 
         layout = gtk_widget_create_pango_layout(ginfo->draw, s.buffer);
         pango_layout_set_font_description(layout, font);
         pango_layout_get_pixel_size(layout, &text_width, &text_height);
 
+        trace_seq_destroy(&s);
+
         /* Lets see if we can print this info */
         if (p2 < text_width)
                 start = 1;
@@ -1967,7 +1970,6 @@ static void draw_timeline(struct graph_info *ginfo, gint width)
                 convert_nano(time, &sec, &usec);
                 trace_seq_init(&s);
                 trace_seq_printf(&s, "%lu.%06lu", sec, usec);
-                trace_seq_destroy(&s);
 
                 gdk_draw_line(ginfo->curr_pixmap, ginfo->draw->style->black_gc,
                               mid, height, mid, height + 5);
@@ -1978,6 +1980,7 @@ static void draw_timeline(struct graph_info *ginfo, gint width)
                 gdk_draw_layout(ginfo->curr_pixmap, ginfo->draw->style->black_gc,
                                 mid - (w / 2), height+10, layout);
                 g_object_unref(layout);
+                trace_seq_destroy(&s);
         }
 }