From: Xin Long
> Sent: 19 January 2017 17:19
> This patch is to implement Sender-Side Procedures for the Add
> Outgoing and Incoming Streams Request Parameter described in
> rfc6525 section 5.1.5-5.1.6.
>
> It is also to add sockopt SCTP_ADD_STREAMS in rfc6525 section
> 6.3.4 for users.
...
> + out = params->sas_outstrms;
> + in = params->sas_instrms;
> +
> + if (!out && !in)
> + goto out;
> +
> + if (out) {
> + __u16 nums = stream->outcnt + out;
Make nums 'unsigned int', the code will be smaller and you can
use the value for the overflow check.
> + /* Check for overflow, can't use nums here */
> + if (stream->outcnt + out > SCTP_MAX_STREAM)
> + goto out;
> +
> + /* Use ksize to check if stream array really needs to realloc */
> + if (ksize(stream->out) / sizeof(*stream->out) < nums) {
> + struct sctp_stream_out *streamout;
> +
> + streamout = kcalloc(nums, sizeof(*streamout),
> + GFP_KERNEL);
> + if (!streamout) {
> + retval = -ENOMEM;
> + goto out;
> + }
> +
> + memcpy(streamout, stream->out,
> + sizeof(*streamout) * stream->outcnt);
> +
> + kfree(stream->out);
> + stream->out = streamout;
> + }
Does kcalloc() zero the entire area, or just the length you ask for?
If the latter you need to zero the rest here.
...
David