From: senhuang42 <senhuang96@fb.com>
Date: Mon, 2 Nov 2020 15:58:18 +0000 (-0500)
Subject: Fix incorrect index increment in merge algorithm
X-Git-Tag: v1.4.7~34^2~11
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e8501e00b8df6bab69838a7bf40f4f9f479a288f;p=thirdparty%2Fzstd.git

Fix incorrect index increment in merge algorithm
---

diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index 1f274622e..7357a70a2 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -2569,22 +2569,24 @@ size_t ZSTD_getSequences(ZSTD_CCtx* zc, ZSTD_Sequence* outSeqs,
     ZSTD_customFree(dst, ZSTD_defaultCMem);
 
     if (format == ZSTD_sf_noBlockDelimiters) {
-        /* Merge the dummy block delimiters */
         size_t i = 0;
         size_t totalSeqs = zc->seqCollector.seqIndex;
-        for (; i < totalSeqs; ++i) {
+        while(i < totalSeqs) {
             if (seqCollector.seqStart[i].offset == 0 && seqCollector.seqStart[i].matchLength == 0) {
                 /* Merge the block boundary or last literals */
                 if (i != totalSeqs-1) {
                     /* Add last literals to next sequence, then "delete" this sequence */
                     seqCollector.seqStart[i+1].litLength += seqCollector.seqStart[i].litLength;
-                    memmove(seqCollector.seqStart+i, seqCollector.seqStart+i+1, (totalSeqs-i-1)*sizeof(ZSTD_sequence));
+                    memmove(seqCollector.seqStart+i, seqCollector.seqStart+i+1, (totalSeqs-i-1)*sizeof(ZSTD_Sequence));
                 }
                 totalSeqs--;
+            } else {
+                ++i;
             }
         }
         zc->seqCollector.seqIndex = totalSeqs;
     }
+    
     return zc->seqCollector.seqIndex;
 }