[gnumeric] Fuzzed file fix. [#751384]

[Jean Bréfort <jbrefort src gnome org>]

commit 71d614dbd7e12cf82eb2bb10a330c3a52d5569d7
Author: Jean Brefort <jean brefort normalesup org>
Date:   Wed Jun 24 08:46:38 2015 +0200

    Fuzzed file fix. [#751384]

 NEWS                     |    2 +-
 plugins/excel/ChangeLog  |    5 +++++
 plugins/excel/ms-chart.c |    3 ++-
 3 files changed, 8 insertions(+), 2 deletions(-)
---
diff --git a/NEWS b/NEWS
index e0e65ec..e8c7a4b 100644
--- a/NEWS
+++ b/NEWS
@@ -15,7 +15,7 @@ Jean:
        * Fix xlsx import of plot area manual layout. [#748016]
        * Fix out of bounds read. [#749121]
        * Fuzzed file fixes.  [#750042] [#751217] [#751270] [#751271]
-          [#751383]
+          [#751383] [#751384]
 
 Morten:
        * Fix import/export of graph backplane.
diff --git a/plugins/excel/ChangeLog b/plugins/excel/ChangeLog
index 967092f..97de5cf 100644
--- a/plugins/excel/ChangeLog
+++ b/plugins/excel/ChangeLog
@@ -1,3 +1,8 @@
+2015-06-24  Jean Brefort  <jean brefort normalesup org>
+
+       * ms-chart.c (end), (ms_excel_chart_read): don't use unexisting series and
+       initialize XLChartReadState::style_element. Fixes #751384.
+
 2015-06-22  Morten Welinder  <terra gnome org>
 
        * ms-escher.c (ms_escher_read_container): Catch crazy length field
diff --git a/plugins/excel/ms-chart.c b/plugins/excel/ms-chart.c
index 5085b33..56b526e 100644
--- a/plugins/excel/ms-chart.c
+++ b/plugins/excel/ms-chart.c
@@ -3017,7 +3017,7 @@ not_a_matrix:
                                g_object_unref (s->dropbar_style);
                                s->dropbar_style = NULL;
                        }
-                       if (s->hilo) {
+                       if (l > 0 && s->hilo) {
                                GogObject *plot = GOG_OBJECT (gog_plot_new_by_name ("GogMinMaxPlot"));
                                if (s->has_extra_dataformat) {
                                        g_object_set (G_OBJECT (plot), "plot-group", "GogStockPlot", NULL);
@@ -3690,6 +3690,7 @@ ms_excel_chart_read (BiffQuery *q, MSContainer *container,
        state.xaxis = NULL;
        state.interpolation = GO_LINE_INTERPOLATION_LINEAR;
        state.error = FALSE;
+       state.style_element = -1;
 
        if (NULL != (state.sog = sog)) {
                state.graph = sheet_object_graph_get_gog (sog);