zstd: Reject empty compressed blocks (#862)

* zstd: Reject empty compressed blocks * Update good inputs Matches zstandard behaviour.
klauspost · Sep 18, 2023 · 6125c11 · 6125c11
1 parent 7b22298
commit 6125c11
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diff --git a/zstd/blockdec.go b/zstd/blockdec.go
@@ -489,6 +489,9 @@ func (b *blockDec) decodeCompressed(hist *history) error {
 		return err
 	}
 	if hist.decoders.nSeqs == 0 {
+		if len(hist.decoders.literals) == 0 {
+			return errors.New("invalid block: no literals nor sequences found")
+		}
 		b.dst = append(b.dst, hist.decoders.literals...)
 		return nil
 	}

diff --git a/zstd/testdata/good.zip b/zstd/testdata/good.zip