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:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To:     Markus Mayer <mmayer@broadcom.com>,
        Broadcom internal kernel review list 
        <bcm-kernel-feedback-list@broadcom.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        Florian Fainelli <f.fainelli@gmail.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH] memory: brcmstb_dpfe: fix testing array offset after use
Date:   Sat, 13 May 2023 13:29:31 +0200
Message-Id: <20230513112931.176066-1-krzysztof.kozlowski@linaro.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Code should first check for valid value of array offset, then use it as
the index.  Fixes smatch warning:

  drivers/memory/brcmstb_dpfe.c:443 __send_command() error: testing array offset 'cmd' after use.

Fixes: 2f330caff577 ("memory: brcmstb: Add driver for DPFE")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 drivers/memory/brcmstb_dpfe.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
index 76c82e9c8fce..9339f80b21c5 100644
--- a/drivers/memory/brcmstb_dpfe.c
+++ b/drivers/memory/brcmstb_dpfe.c
@@ -434,15 +434,17 @@ static void __finalize_command(struct brcmstb_dpfe_priv *priv)
 static int __send_command(struct brcmstb_dpfe_priv *priv, unsigned int cmd,
 			  u32 result[])
 {
-	const u32 *msg = priv->dpfe_api->command[cmd];
 	void __iomem *regs = priv->regs;
 	unsigned int i, chksum, chksum_idx;
+	const u32 *msg;
 	int ret = 0;
 	u32 resp;
 
 	if (cmd >= DPFE_CMD_MAX)
 		return -1;
 
+	msg = priv->dpfe_api->command[cmd];
+
 	mutex_lock(&priv->lock);
 
 	/* Wait for DCPU to become ready */
-- 
2.34.1