Re: [PATCH net-next] xprtrdma: Use struct_size() in kzalloc()

[Chuck Lever <chuck.lever@oracle.com>]

Hi Gustavo-

Anna is supposed to take patches for xprtrdma/ .


> On May 23, 2019, at 6:36 PM, Gustavo A. R. Silva <gustavo@embeddedor.com> wrote:
> 
> Hi Dave,
> 
> I wonder if you can take this patch.
> 
> Thanks
> --
> Gustavo
> 
> On 3/28/19 3:41 PM, Gustavo A. R. Silva wrote:
>> Hi all,
>> 
>> Friendly ping:
>> 
>> Who can take this?
>> 
>> Thanks
>> --
>> Gustavo
>> 
>> On 1/31/19 8:11 AM, Chuck Lever wrote:
>>> 
>>> 
>>>> On Jan 30, 2019, at 7:46 PM, Gustavo A. R. Silva <gustavo@embeddedor.com> 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 foo {
>>>>   int stuff;
>>>>   struct boo entry[];
>>>> };
>>>> 
>>>> instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), 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 code was detected with the help of Coccinelle.
>>>> 
>>>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
>>> 
>>> Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
>>> 
>>> 
>>>> ---
>>>> net/sunrpc/xprtrdma/verbs.c | 3 +--
>>>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>>> 
>>>> diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
>>>> index 4994e75945b8..9e8cf7456840 100644
>>>> --- a/net/sunrpc/xprtrdma/verbs.c
>>>> +++ b/net/sunrpc/xprtrdma/verbs.c
>>>> @@ -811,8 +811,7 @@ static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ia *ia)
>>>> {
>>>> 	struct rpcrdma_sendctx *sc;
>>>> 
>>>> -	sc = kzalloc(sizeof(*sc) +
>>>> -		     ia->ri_max_send_sges * sizeof(struct ib_sge),
>>>> +	sc = kzalloc(struct_size(sc, sc_sges, ia->ri_max_send_sges),
>>>> 		     GFP_KERNEL);
>>>> 	if (!sc)
>>>> 		return NULL;
>>>> -- 
>>>> 2.20.1
>>>> 
>>> 
>>> --
>>> Chuck Lever
>>> 
>>> 
>>> 

--
Chuck Lever