From b87e64e3206210580f4a6df2d77f9ae3f1033039 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Felix=20H=C3=BCttner?= <felix.huettner@mail.schwarz>
Date: Thu, 6 May 2021 12:18:00 -0400
Subject: [PATCH] rgw: RGWSwiftWebsiteHandler::is_web_dir checks empty
 subdir_name

checking for empty name avoids later assertion in RGWObjectCtx::set_atomic

Fixes: CVE-2021-3531

Reviewed-by: Casey Bodley <cbodley@redhat.com>
Signed-off-by: Casey Bodley <cbodley@redhat.com>
(cherry picked from commit 7196a469b4470f3c8628489df9a41ec8b00a5610)
---
 src/rgw/rgw_rest_swift.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/rgw/rgw_rest_swift.cc b/src/rgw/rgw_rest_swift.cc
index fb392828a42ac..c358a42f8ee03 100644
--- a/src/rgw/rgw_rest_swift.cc
+++ b/src/rgw/rgw_rest_swift.cc
@@ -2549,6 +2549,9 @@ bool RGWSwiftWebsiteHandler::is_web_dir() const
     return false;
   } else if (subdir_name.back() == '/') {
     subdir_name.pop_back();
+    if (subdir_name.empty()) {
+      return false;
+    }
   }
 
   rgw_obj obj(s->bucket, std::move(subdir_name));