Avoid undefined negation behavior if windowBits is INT_MIN.

Author: Mark Adler

deflate.c

@@ -279,6 +279,8 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
 
     if (windowBits < 0) { /* suppress zlib wrapper */
         wrap = 0;
+        if (windowBits < -15)
+            return Z_STREAM_ERROR;
         windowBits = -windowBits;
     }
 #ifdef GZIP

inflate.c

@@ -168,6 +168,8 @@ int windowBits;
 
     /* extract wrap request from windowBits parameter */
     if (windowBits < 0) {
+        if (windowBits < -15)
+            return Z_STREAM_ERROR;
         wrap = 0;
         windowBits = -windowBits;
     }