From 06ca9c7d7ce2c9883551ab1e4c535f6a456b5e5d Mon Sep 17 00:00:00 2001
From: Yann Collet <cyan@fb.com>
Date: Tue, 6 Mar 2018 01:50:19 -0800
Subject: [PATCH] fixed 0-seq blocks in block-decompression mode

---
 lib/decompress/zstd_decompress.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/decompress/zstd_decompress.c b/lib/decompress/zstd_decompress.c
index 12c46e572..53f555337 100644
--- a/lib/decompress/zstd_decompress.c
+++ b/lib/decompress/zstd_decompress.c
@@ -1331,7 +1331,8 @@ static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
         ip += seqHSize;
         srcSize -= seqHSize;
 
-        if (dctx->fParams.windowSize > (1<<24)) {
+        if ( (dctx->fParams.windowSize > (1<<24) || !frame)
+          && (nbSeq>0) ) {  /* could probably use a larger nbSeq limit */
             U32 const shareLongOffsets = ZSTD_getLongOffsetsShare(dctx->OFTptr);
             U32 const minShare = MEM_64bits() ? 7 : 20;
             if (shareLongOffsets >= minShare)