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:   Russ Weight <russell.h.weight@intel.com>
To:     mdf@kernel.org, hao.wu@intel.com, yilun.xu@intel.com,
        trix@redhat.com, linux-fpga@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     lgoncalv@redhat.com, marpagan@redhat.com,
        matthew.gerlach@linux.intel.com,
        basheer.ahmed.muddebihal@intel.com, tianfei.zhang@intel.com,
        Russ Weight <russell.h.weight@intel.com>,
        kernel test robot <lkp@intel.com>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        stable@vger.kernel.org
Subject: [PATCH v1 1/1] fpga: m10bmc-sec: Fix possible memory leak of flash_buf
Date:   Fri, 16 Sep 2022 16:52:05 -0700
Message-Id: <20220916235205.106873-1-russell.h.weight@intel.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

There is an error check following the allocation of flash_buf that returns
without freeing flash_buf. It makes more sense to do the error check
before the allocation and the reordering eliminates the memory leak.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 154afa5c31cd ("fpga: m10bmc-sec: expose max10 flash update count")
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Cc: <stable@vger.kernel.org>
---
 drivers/fpga/intel-m10-bmc-sec-update.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/fpga/intel-m10-bmc-sec-update.c b/drivers/fpga/intel-m10-bmc-sec-update.c
index 526c8cdd1474..79d48852825e 100644
--- a/drivers/fpga/intel-m10-bmc-sec-update.c
+++ b/drivers/fpga/intel-m10-bmc-sec-update.c
@@ -148,10 +148,6 @@ static ssize_t flash_count_show(struct device *dev,
 	stride = regmap_get_reg_stride(sec->m10bmc->regmap);
 	num_bits = FLASH_COUNT_SIZE * 8;
 
-	flash_buf = kmalloc(FLASH_COUNT_SIZE, GFP_KERNEL);
-	if (!flash_buf)
-		return -ENOMEM;
-
 	if (FLASH_COUNT_SIZE % stride) {
 		dev_err(sec->dev,
 			"FLASH_COUNT_SIZE (0x%x) not aligned to stride (0x%x)\n",
@@ -160,6 +156,10 @@ static ssize_t flash_count_show(struct device *dev,
 		return -EINVAL;
 	}
 
+	flash_buf = kmalloc(FLASH_COUNT_SIZE, GFP_KERNEL);
+	if (!flash_buf)
+		return -ENOMEM;
+
 	ret = regmap_bulk_read(sec->m10bmc->regmap, STAGING_FLASH_COUNT,
 			       flash_buf, FLASH_COUNT_SIZE / stride);
 	if (ret) {
-- 
2.25.1