diff --git a/programs/fileio.c b/programs/fileio.c
index ec939083..5693ac39 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -951,7 +951,7 @@ static void FIO_adjustParamsForPatchFromMode(FIO_prefs_t* const prefs,
     FIO_adjustMemLimitForPatchFromMode(prefs, dictSize, maxSrcFileSize);
     if (fileWindowLog > ZSTD_WINDOWLOG_MAX)
         DISPLAYLEVEL(1, "Max window log exceeded by file (compression ratio will suffer)\n");
-    comprParams->windowLog = MIN(ZSTD_WINDOWLOG_MAX, fileWindowLog);
+    comprParams->windowLog = MAX(ZSTD_WINDOWLOG_MIN, MIN(ZSTD_WINDOWLOG_MAX, fileWindowLog));
     if (fileWindowLog > ZSTD_cycleLog(cParams.chainLog, cParams.strategy)) {
         if (!prefs->ldmFlag)
             DISPLAYLEVEL(1, "long mode automatically triggered\n");