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From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
To: Andy Gross <agross@kernel.org>, Ohad Ben-Cohen <ohad@wizery.com>,
	Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: linux-arm-msm@vger.kernel.org, linux-remoteproc@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	"Gustavo A. R. Silva" <gustavo@embeddedor.com>
Subject: [PATCH] rpmsg: glink: Use struct_size() helper
Date: Thu, 29 Aug 2019 13:17:21 -0500	[thread overview]
Message-ID: <20190829181721.GA22554@embeddedor> (raw)

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct {
	...
	struct intent_pair intents[];
} __packed * msg;

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

So, replace the following form:

sizeof(*msg) + sizeof(struct intent_pair) * count

with:

struct_size(msg, intents, count)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 drivers/rpmsg/qcom_glink_native.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index f46c787733e8..621f1afd4d6b 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -892,7 +892,7 @@ static void qcom_glink_handle_intent(struct qcom_glink *glink,
 		struct intent_pair intents[];
 	} __packed * msg;
 
-	const size_t msglen = sizeof(*msg) + sizeof(struct intent_pair) * count;
+	const size_t msglen = struct_size(msg, intents, count);
 	int ret;
 	int i;
 	unsigned long flags;
-- 
2.23.0


             reply	other threads:[~2019-08-29 18:22 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-29 18:17 Gustavo A. R. Silva [this message]
2019-08-29 19:09 ` [PATCH] rpmsg: glink: Use struct_size() helper Bjorn Andersson
2019-08-29 19:15   ` Gustavo A. R. Silva

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