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Date:   Wed, 29 Sep 2021 17:29:22 -0500
From:   "Gustavo A. R. Silva" <gustavoars@kernel.org>
To:     Vinod Koul <vkoul@kernel.org>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc:     dmaengine@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        linux-hardening@vger.kernel.org
Subject: [PATCH][next] dmaengine: stm32-mdma: Use struct_size() helper in
 devm_kzalloc()
Message-ID: <20210929222922.GA357509@embeddedor>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
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Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows that,
in the worse scenario, could lead to heap overflows.

Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
 drivers/dma/stm32-mdma.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
index 18cbd1e43c2e..d30a4a28d3bf 100644
--- a/drivers/dma/stm32-mdma.c
+++ b/drivers/dma/stm32-mdma.c
@@ -1566,7 +1566,8 @@ static int stm32_mdma_probe(struct platform_device *pdev)
 	if (count < 0)
 		count = 0;
 
-	dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev) + sizeof(u32) * count,
+	dmadev = devm_kzalloc(&pdev->dev,
+			      struct_size(dmadev, ahb_addr_masks, count),
 			      GFP_KERNEL);
 	if (!dmadev)
 		return -ENOMEM;
-- 
2.27.0