diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index 84e756b88..aac61be6a 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -2311,19 +2311,19 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
     U32 const dictIDSizeCode = (dictID>0) + (dictID>=256) + (dictID>=65536);   /* 0-3 */
     U32 const checksumFlag = params.fParams.checksumFlag>0;
     U32 const windowSize = 1U << params.cParams.windowLog;
-    U32 const directModeFlag = params.fParams.contentSizeFlag && (windowSize > (pledgedSrcSize-1));
+    U32 const singleSegment = params.fParams.contentSizeFlag && (windowSize > (pledgedSrcSize-1));
     BYTE const windowLogByte = (BYTE)((params.cParams.windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN) << 3);
     U32 const fcsCode = params.fParams.contentSizeFlag ?
                      (pledgedSrcSize>=256) + (pledgedSrcSize>=65536+256) + (pledgedSrcSize>=0xFFFFFFFFU) :   /* 0-3 */
                       0;
-    BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (directModeFlag<<5) + (fcsCode<<6) );
+    BYTE const frameHeaderDecriptionByte = (BYTE)(dictIDSizeCode + (checksumFlag<<2) + (singleSegment<<5) + (fcsCode<<6) );
     size_t pos;
 
     if (dstCapacity < ZSTD_frameHeaderSize_max) return ERROR(dstSize_tooSmall);
 
     MEM_writeLE32(dst, ZSTD_MAGICNUMBER);
     op[4] = frameHeaderDecriptionByte; pos=5;
-    if (!directModeFlag) op[pos++] = windowLogByte;
+    if (!singleSegment) op[pos++] = windowLogByte;
     switch(dictIDSizeCode)
     {
         default:   /* impossible */
@@ -2335,7 +2335,7 @@ static size_t ZSTD_writeFrameHeader(void* dst, size_t dstCapacity,
     switch(fcsCode)
     {
         default:   /* impossible */
-        case 0 : if (directModeFlag) op[pos++] = (BYTE)(pledgedSrcSize); break;
+        case 0 : if (singleSegment) op[pos++] = (BYTE)(pledgedSrcSize); break;
         case 1 : MEM_writeLE16(op+pos, (U16)(pledgedSrcSize-256)); pos+=2; break;
         case 2 : MEM_writeLE32(op+pos, (U32)(pledgedSrcSize)); pos+=4; break;
         case 3 : MEM_writeLE64(op+pos, (U64)(pledgedSrcSize)); pos+=8; break;
diff --git a/lib/decompress/zstd_decompress.c b/lib/decompress/zstd_decompress.c
index cc61627f2..2940dd68a 100644
--- a/lib/decompress/zstd_decompress.c
+++ b/lib/decompress/zstd_decompress.c
@@ -204,10 +204,10 @@ static size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize)
     if (srcSize < ZSTD_frameHeaderSize_min) return ERROR(srcSize_wrong);
     {   BYTE const fhd = ((const BYTE*)src)[4];
         U32 const dictID= fhd & 3;
-        U32 const directMode = (fhd >> 5) & 1;
+        U32 const singleSegment = (fhd >> 5) & 1;
         U32 const fcsId = fhd >> 6;
-        return ZSTD_frameHeaderSize_min + !directMode + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId]
-                + (directMode && !ZSTD_fcs_fieldSize[fcsId]);
+        return ZSTD_frameHeaderSize_min + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId]
+                + (singleSegment && !ZSTD_fcs_fieldSize[fcsId]);
     }
 }
 
@@ -241,14 +241,14 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
         size_t pos = 5;
         U32 const dictIDSizeCode = fhdByte&3;
         U32 const checksumFlag = (fhdByte>>2)&1;
-        U32 const directMode = (fhdByte>>5)&1;
+        U32 const singleSegment = (fhdByte>>5)&1;
         U32 const fcsID = fhdByte>>6;
         U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX;
         U32 windowSize = 0;
         U32 dictID = 0;
         U64 frameContentSize = 0;
         if ((fhdByte & 0x08) != 0) return ERROR(frameParameter_unsupported);   /* reserved bits, which must be zero */
-        if (!directMode) {
+        if (!singleSegment) {
             BYTE const wlByte = ip[pos++];
             U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
             if (windowLog > ZSTD_WINDOWLOG_MAX) return ERROR(frameParameter_unsupported);
@@ -267,7 +267,7 @@ size_t ZSTD_getFrameParams(ZSTD_frameParams* fparamsPtr, const void* src, size_t
         switch(fcsID)
         {
             default:   /* impossible */
-            case 0 : if (directMode) frameContentSize = ip[pos]; break;
+            case 0 : if (singleSegment) frameContentSize = ip[pos]; break;
             case 1 : frameContentSize = MEM_readLE16(ip+pos)+256; break;
             case 2 : frameContentSize = MEM_readLE32(ip+pos); break;
             case 3 : frameContentSize = MEM_readLE64(ip+pos); break;
@@ -849,7 +849,6 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
                                  const void* src, size_t srcSize)
 {
     const BYTE* ip = (const BYTE*)src;
-    const BYTE* const iend = ip + srcSize;
     BYTE* const ostart = (BYTE* const)dst;
     BYTE* const oend = ostart + dstCapacity;
     BYTE* op = ostart;
@@ -860,9 +859,11 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
 
     /* Frame Header */
     {   size_t const frameHeaderSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_min);
+        size_t result;
         if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
         if (srcSize < frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
-        if (ZSTD_decodeFrameHeader(dctx, src, frameHeaderSize)) return ERROR(corruption_detected);
+        result = ZSTD_decodeFrameHeader(dctx, src, frameHeaderSize);
+        if (ZSTD_isError(result)) return result;
         ip += frameHeaderSize; remainingSize -= frameHeaderSize;
     }
 
@@ -870,7 +871,7 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
     while (1) {
         size_t decodedSize;
         blockProperties_t blockProperties;
-        size_t const cBlockSize = ZSTD_getcBlockSize(ip, iend-ip, &blockProperties);
+        size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
         if (ZSTD_isError(cBlockSize)) return cBlockSize;
 
         ip += ZSTD_blockHeaderSize;