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* [PATCH] drivers: qcom: rpmh: use struct_size() in kzalloc()
@ 2018-12-24  6:22 Gustavo A. R. Silva
  2019-01-09 17:38 ` Gustavo A. R. Silva
  2019-01-29  5:26 ` Amit Kucheria
  0 siblings, 2 replies; 8+ messages in thread
From: Gustavo A. R. Silva @ 2018-12-24  6:22 UTC (permalink / raw)
  To: Andy Gross, David Brown; +Cc: linux-arm-msm, linux-kernel, Gustavo A. R. Silva

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 foo {
    int stuff;
    void *entry[];
};

instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This issue was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 drivers/soc/qcom/rpmh.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
index c7beb6841289..12c057a0b325 100644
--- a/drivers/soc/qcom/rpmh.c
+++ b/drivers/soc/qcom/rpmh.c
@@ -362,8 +362,7 @@ int rpmh_write_batch(const struct device *dev, enum rpmh_state state,
 	if (!count)
 		return -EINVAL;
 
-	req = kzalloc(sizeof(*req) + count * sizeof(req->rpm_msgs[0]),
-		      GFP_ATOMIC);
+	req = kzalloc(struct_size(req, rpm_msgs, count), GFP_ATOMIC);
 	if (!req)
 		return -ENOMEM;
 	req->count = count;
-- 
2.17.0


^ permalink raw reply related	[flat|nested] 8+ messages in thread
* [PATCH] drivers: qcom: rpmh: use struct_size() in kzalloc()
@ 2018-08-24  1:17 Gustavo A. R. Silva
  2018-08-24  3:05 ` Kees Cook
  2018-09-03 19:07 ` Bjorn Andersson
  0 siblings, 2 replies; 8+ messages in thread
From: Gustavo A. R. Silva @ 2018-08-24  1:17 UTC (permalink / raw)
  To: Andy Gross, David Brown
  Cc: linux-arm-msm, linux-soc, linux-kernel, Kees Cook, Gustavo A. R. Silva

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 foo {
	int stuff;
        void *entry[];
};

instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_ATOMIC);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_ATOMIC);

This issue was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 drivers/soc/qcom/rpmh.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
index c7beb68..12c057a 100644
--- a/drivers/soc/qcom/rpmh.c
+++ b/drivers/soc/qcom/rpmh.c
@@ -362,8 +362,7 @@ int rpmh_write_batch(const struct device *dev, enum rpmh_state state,
 	if (!count)
 		return -EINVAL;
 
-	req = kzalloc(sizeof(*req) + count * sizeof(req->rpm_msgs[0]),
-		      GFP_ATOMIC);
+	req = kzalloc(struct_size(req, rpm_msgs, count), GFP_ATOMIC);
 	if (!req)
 		return -ENOMEM;
 	req->count = count;
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2019-01-29  6:58 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-12-24  6:22 [PATCH] drivers: qcom: rpmh: use struct_size() in kzalloc() Gustavo A. R. Silva
2019-01-09 17:38 ` Gustavo A. R. Silva
2019-01-29  5:12   ` Gustavo A. R. Silva
2019-01-29  5:26 ` Amit Kucheria
2019-01-29  6:57   ` Gustavo A. R. Silva
  -- strict thread matches above, loose matches on Subject: below --
2018-08-24  1:17 Gustavo A. R. Silva
2018-08-24  3:05 ` Kees Cook
2018-09-03 19:07 ` Bjorn Andersson

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