diff --git a/src/common/torgzip.c b/src/common/torgzip.c
index c08ed514d8..aca8386cc7 100644
--- a/src/common/torgzip.c
+++ b/src/common/torgzip.c
@@ -348,6 +348,8 @@ tor_zlib_process(tor_zlib_state_t *state,
     case Z_STREAM_END:
       return TOR_ZLIB_DONE;
     case Z_BUF_ERROR:
+      if (state->stream.avail_in == 0)
+        return Z_OK;
       return TOR_ZLIB_BUF_FULL;
     case Z_OK:
       if (state->stream.avail_out == 0)