Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>
To:     linux-kselftest@vger.kernel.org,
        Reinette Chatre <reinette.chatre@intel.com>,
        Shuah Khan <shuah@kernel.org>,
        Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com>,
        Colin Ian King <colin.i.king@gmail.com>,
        linux-kernel@vger.kernel.org
Cc:     =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>
Subject: [PATCH v5 02/19] selftests/resctrl: Don't leak buffer in fill_cache()
Date:   Mon, 17 Jul 2023 16:14:50 +0300
Message-Id: <20230717131507.32420-3-ilpo.jarvinen@linux.intel.com>
In-Reply-To: <20230717131507.32420-1-ilpo.jarvinen@linux.intel.com>
References: <20230717131507.32420-1-ilpo.jarvinen@linux.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

The error path in fill_cache() does return before the allocated buffer
is freed leaking the buffer.

The leak was introduced when fill_cache_read() started to return errors
in commit c7b607fa9325 ("selftests/resctrl: Fix null pointer
dereference on open failed"), before that both fill functions always
returned 0.

Move free() earlier to prevent the mem leak.

Fixes: c7b607fa9325 ("selftests/resctrl: Fix null pointer dereference on open failed")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
 tools/testing/selftests/resctrl/fill_buf.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/resctrl/fill_buf.c b/tools/testing/selftests/resctrl/fill_buf.c
index 341cc93ca84c..3b328c844896 100644
--- a/tools/testing/selftests/resctrl/fill_buf.c
+++ b/tools/testing/selftests/resctrl/fill_buf.c
@@ -177,12 +177,13 @@ fill_cache(unsigned long long buf_size, int malloc_and_init, int memflush,
 	else
 		ret = fill_cache_write(start_ptr, end_ptr, resctrl_val);
 
+	free(startptr);
+
 	if (ret) {
 		printf("\n Error in fill cache read/write...\n");
 		return -1;
 	}
 
-	free(startptr);
 
 	return 0;
 }
-- 
2.30.2