Fix undefined behavior when decoding varint

[folly.git] / folly / Varint.h

diff --git a/folly/Varint.h b/folly/Varint.h
index cd44d2676990c1bfefa4b3d06670f5476103b8bb..2f53dcf13058d0afaf44de6da1ceef0bb1e5204d 100644 (file)
--- a/folly/Varint.h
+++ b/folly/Varint.h
@@ -145,7 +145,7 @@ inline Expected<uint64_t, DecodeVarintError> tryDecodeVarint(Range<T*>& data) {
       b = *p++; val |= (b & 0x7f) << 42; if (b >= 0) break;
       b = *p++; val |= (b & 0x7f) << 49; if (b >= 0) break;
       b = *p++; val |= (b & 0x7f) << 56; if (b >= 0) break;
-      b = *p++; val |= (b & 0x7f) << 63; if (b >= 0) break;
+      b = *p++; val |= (b & 0x01) << 63; if (b >= 0) break;
       return makeUnexpected(DecodeVarintError::TooManyBytes);
     } while (false);
   } else {