Don't use chunkunroll for inflateBack

If the output buffer and the window buffer are the same
memory allocation, we cannot make the assumptions that chunkunroll
does, that it is okay to overwrite the output buffer.

diff --git a/inffast_tpl.h b/inffast_tpl.h
index 9ddd187d84731ca741d7dcca1516d40d2d2da33e..c8f478675437ced464d706ba3461b2dff20b07c0 100644 (file)
--- a/inffast_tpl.h
+++ b/inffast_tpl.h
@@ -249,7 +249,8 @@ void Z_INTERNAL INFLATE_FAST(PREFIX3(stream) *strm, uint32_t start) {
                     if (op < len) {             /* still need some from output */
                         len -= op;
                         out = chunkcopy_safe(out, from, op, safe);
-                        out = CHUNKUNROLL(out, &dist, &len);
+                        if (!extra_safe)
+                            out = CHUNKUNROLL(out, &dist, &len);
                         out = chunkcopy_safe(out, out - dist, len, safe);
                     } else {
                         out = chunkcopy_safe(out, from, len, safe);