Hi Anna,
On 16.02.2022 18:30, Anna Schumaker wrote:
> On Tue, Feb 15, 2022 at 5:17 AM Alexey Khoroshilov
> <khoroshilov@xxxxxxxxx> wrote:
>>
>> Overflow check in not needed anymore after we switch to kmalloc_array().
>
> Don't we still need the overflow check since 'n' is used in the
> for-loop end condition farther down in this function?
It is not, because it will be detected by kmalloc_array(), it returns
NULL and we will go out before the loop:
args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
if (!args->devs) {
status = htonl(NFS4ERR_DELAY);
goto out;
}
Best regards,
Alexey
>>
>> Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
>> Fixes: a4f743a6bb20 ("NFSv4.1: Convert open-coded array allocation calls to kmalloc_array()")
>> ---
>> fs/nfs/callback_xdr.c | 4 ----
>> 1 file changed, 4 deletions(-)
>>
>> diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
>> index f90de8043b0f..8dcb08e1a885 100644
>> --- a/fs/nfs/callback_xdr.c
>> +++ b/fs/nfs/callback_xdr.c
>> @@ -271,10 +271,6 @@ __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
>> n = ntohl(*p++);
>> if (n == 0)
>> goto out;
>> - if (n > ULONG_MAX / sizeof(*args->devs)) {
>> - status = htonl(NFS4ERR_BADXDR);
>> - goto out;
>> - }
>>
>> args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
>> if (!args->devs) {
>> --
>> 2.7.4
>>
