--- src/contrib/bzip2/Attic/decompress.c	2003/06/17 02:43:38	1.1
+++ src/contrib/bzip2/Attic/decompress.c	2005/06/29 23:16:15	1.1.2.1
@@ -524,17 +524,23 @@ Int32 BZ2_decompress ( DState* s )
       if (s->origPtr < 0 || s->origPtr >= nblock)
          RETURN(BZ_DATA_ERROR);
 
+      /*-- Set up cftab to facilitate generation of T^(-1) --*/
+      s->cftab[0] = 0;
+      for (i = 1; i <= 256; i++) s->cftab[i] = s->unzftab[i-1];
+      for (i = 1; i <= 256; i++) s->cftab[i] += s->cftab[i-1];
+      for (i = 0; i <= 256; i++) {
+         if (s->cftab[i] < 0 || s->cftab[i] > nblock) {
+            /* s->cftab[i] can legitimately be == nblock */
+            RETURN(BZ_DATA_ERROR);
+         }
+      }
+
       s->state_out_len = 0;
       s->state_out_ch  = 0;
       BZ_INITIALISE_CRC ( s->calculatedBlockCRC );
       s->state = BZ_X_OUTPUT;
       if (s->verbosity >= 2) VPrintf0 ( "rt+rld" );
 
-      /*-- Set up cftab to facilitate generation of T^(-1) --*/
-      s->cftab[0] = 0;
-      for (i = 1; i <= 256; i++) s->cftab[i] = s->unzftab[i-1];
-      for (i = 1; i <= 256; i++) s->cftab[i] += s->cftab[i-1];
-
       if (s->smallDecompress) {
 
          /*-- Make a copy of cftab, used in generation of T --*/