rgw_file: avoid string::front() on empty path

Fixes: https://tracker.ceph.com/issues/43548
Signed-off-by: Matt Benjamin <mbenjamin@redhat.com>
(cherry picked from commit 2136b9873cdfe3440eed19423b9675c6a8b93f03)

diff --git a/src/rgw/rgw_file.h b/src/rgw/rgw_file.h
index 84b17069e20f4829f919115547a57ca03f276cca..0bf488a579b46ec3ab3fcf8b1ee91c2a587bfdc7 100644 (file)
--- a/src/rgw/rgw_file.h
+++ b/src/rgw/rgw_file.h
@@ -510,7 +510,8 @@ namespace rgw {
        if (pos > 1) {
          path += "/";
        } else {
-         if (!omit_bucket && (path.front() != '/')) // pretty-print
+         if (!omit_bucket &&
+             ((path.length() == 0) || (path.front() != '/')))
            path += "/";
        }
        path += *s;