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

From: Gustavo A. R. Silva
Date: Thu May 23 2019 - 18:39:03 EST


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@xxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxx>
>>
>> Reviewed-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
>>
>>
>>> ---
>>> 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
>>
>>
>>