dr_55: Add boundary checking.

src/descriptors/dr_55.c

@@ -66,6 +66,8 @@ dvbpsi_parental_rating_dr_t * dvbpsi_DecodeParentalRatingDr(
         return NULL;
 
     int i_ratings_number = p_descriptor->i_length / 4;
+    if (i_ratings_number > DVBPSI_PARENTAL_RATING_DR_MAX)
+        i_ratings_number = DVBPSI_PARENTAL_RATING_DR_MAX;
     p_decoded->i_ratings_number = i_ratings_number;
 
     for (int i = 0; i < i_ratings_number; i++)
@@ -91,6 +93,9 @@ dvbpsi_descriptor_t * dvbpsi_GenParentalRatingDr(
                                         dvbpsi_parental_rating_dr_t * p_decoded,
                                         bool b_duplicate)
 {    
+    if (p_decoded->i_ratings_number > DVBPSI_PARENTAL_RATING_DR_MAX)
+        p_decoded->i_ratings_number = DVBPSI_PARENTAL_RATING_DR_MAX;
+
     /* Create the descriptor */
     dvbpsi_descriptor_t * p_descriptor =
             dvbpsi_NewDescriptor(0x55, p_decoded->i_ratings_number * 4 , NULL);

src/descriptors/dr_55.h

@@ -58,6 +58,12 @@ typedef struct dvbpsi_parental_rating_s
 
 } dvbpsi_parental_rating_t;
 
+/*!
+ * \def DVBPSI_PARENTAL_RATING_DR_MAX
+ * \brief Maximum number of dvbpsi_parental_rating_t entries present in
+ * @see dvbpsi_parental_rating_t
+ */
+#define DVBPSI_PARENTAL_RATING_DR_MAX 64
 
 /*****************************************************************************
  * dvbpsi_parental_rating_dr_t
@@ -76,7 +82,8 @@ typedef struct dvbpsi_parental_rating_s
 typedef struct dvbpsi_parental_rating_dr_s
 {
   uint8_t       i_ratings_number;                   /*!< number of rating */
-  dvbpsi_parental_rating_t p_parental_rating[64];   /*!< parental rating table */
+  dvbpsi_parental_rating_t
+                p_parental_rating[DVBPSI_PARENTAL_RATING_DR_MAX]; /*!< parental rating table */
 
 } dvbpsi_parental_rating_dr_t;