| Message ID | 20190829181721.GA22554@embeddedor (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | rpmsg: glink: Use struct_size() helper | expand |
On Thu 29 Aug 11:17 PDT 2019, Gustavo A. R. Silva wrote: > 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> Applied, thanks! > --- > 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 >
On 8/29/19 2:09 PM, Bjorn Andersson wrote: > On Thu 29 Aug 11:17 PDT 2019, Gustavo A. R. Silva wrote: > >> 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> > > Applied, thanks! > Awesome. :) Thanks! -- Gustavo
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;
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(-)