[libxslt] Fix double to int conversion

[Nick Wellnhofer <nwellnhof src gnome org>]

commit df87857190d008b2d14fb500dac05c878c9ad1d7
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Thu May 18 17:14:28 2017 +0200

    Fix double to int conversion
    
    Add range checks to avoid undefined behavior.
    
    Limit str:padding length to 100,000 chars.

 libexslt/date.c    |   44 ++++++++++++++++++++++++--------------------
 libexslt/strings.c |   12 +++++++++++-
 2 files changed, 35 insertions(+), 21 deletions(-)
---
diff --git a/libexslt/date.c b/libexslt/date.c
index ba7097d..220d71d 100644
--- a/libexslt/date.c
+++ b/libexslt/date.c
@@ -2096,11 +2096,12 @@ exsltDateMonthName (const xmlChar *dateTime)
        { 'N', 'o', 'v', 'e', 'm', 'b', 'e', 'r', 0 },
        { 'D', 'e', 'c', 'e', 'm', 'b', 'e', 'r', 0 }
     };
-    int month;
-    month = (int) exsltDateMonthInYear(dateTime);
-    if (!VALID_MONTH(month))
-      month = 0;
-    return monthNames[month];
+    double month;
+    int index = 0;
+    month = exsltDateMonthInYear(dateTime);
+    if (!xmlXPathIsNaN(month) && (month >= 1.0) && (month <= 12.0))
+      index = (int) month;
+    return monthNames[index];
 }
 
 /**
@@ -2144,11 +2145,12 @@ exsltDateMonthAbbreviation (const xmlChar *dateTime)
        { 'N', 'o', 'v', 0 },
        { 'D', 'e', 'c', 0 }
     };
-    int month;
-    month = (int) exsltDateMonthInYear(dateTime);
-    if(!VALID_MONTH(month))
-      month = 0;
-    return monthAbbreviations[month];
+    double month;
+    int index = 0;
+    month = exsltDateMonthInYear(dateTime);
+    if (!xmlXPathIsNaN(month) && (month >= 1.0) && (month <= 12.0))
+      index = (int) month;
+    return monthAbbreviations[index];
 }
 
 /**
@@ -2504,11 +2506,12 @@ exsltDateDayName (const xmlChar *dateTime)
        { 'F', 'r', 'i', 'd', 'a', 'y', 0 },
        { 'S', 'a', 't', 'u', 'r', 'd', 'a', 'y', 0 }
     };
-    int day;
-    day = (int) exsltDateDayInWeek(dateTime);
-    if((day < 1) || (day > 7))
-      day = 0;
-    return dayNames[day];
+    double day;
+    int index = 0;
+    day = exsltDateDayInWeek(dateTime);
+    if(!xmlXPathIsNaN(day) && (day >= 1.0) && (day <= 7.0))
+      index = (int) day;
+    return dayNames[index];
 }
 
 /**
@@ -2544,11 +2547,12 @@ exsltDateDayAbbreviation (const xmlChar *dateTime)
        { 'F', 'r', 'i', 0 },
        { 'S', 'a', 't', 0 }
     };
-    int day;
-    day = (int) exsltDateDayInWeek(dateTime);
-    if((day < 1) || (day > 7))
-      day = 0;
-    return dayAbbreviations[day];
+    double day;
+    int index = 0;
+    day = exsltDateDayInWeek(dateTime);
+    if(!xmlXPathIsNaN(day) && (day >= 1.0) && (day <= 7.0))
+      index = (int) day;
+    return dayAbbreviations[index];
 }
 
 /**
diff --git a/libexslt/strings.c b/libexslt/strings.c
index 62f76fb..9be90b5 100644
--- a/libexslt/strings.c
+++ b/libexslt/strings.c
@@ -342,6 +342,7 @@ exsltStrDecodeUriFunction (xmlXPathParserContextPtr ctxt, int nargs) {
 static void
 exsltStrPaddingFunction (xmlXPathParserContextPtr ctxt, int nargs) {
     int number, str_len = 0, str_size = 0;
+    double floatval;
     xmlChar *str = NULL, *ret = NULL;
 
     if ((nargs < 1) || (nargs > 2)) {
@@ -361,7 +362,16 @@ exsltStrPaddingFunction (xmlXPathParserContextPtr ctxt, int nargs) {
        str_size = 1;
     }
 
-    number = (int) xmlXPathPopNumber(ctxt);
+    floatval = xmlXPathPopNumber(ctxt);
+
+    if (xmlXPathIsNaN(floatval) || floatval < 0.0) {
+        number = 0;
+    } else if (floatval >= 100000.0) {
+        number = 100000;
+    }
+    else {
+        number = (int) floatval;
+    }
 
     if (number <= 0) {
        xmlXPathReturnEmptyString(ctxt);