diff --git a/Modules/_lzmamodule.c b/Modules/_lzmamodule.c
index 5e158fd..6e394c5 100644
--- a/Modules/_lzmamodule.c
+++ b/Modules/_lzmamodule.c
@@ -995,8 +995,10 @@ decompress(Decompressor *d, uint8_t *data, size_t len, Py_ssize_t max_length)
     }
 
     result = decompress_buf(d, max_length);
-    if(result == NULL)
+    if(result == NULL) {
+        lzs->next_in = 0;
         return NULL;
+    }
 
     if (d->eof) {
         d->needs_input = 0;