Re: [PATCH v2] brcmfmac: Fix glom_skb leak in brcmf_sdiod_recv_chain

From: Andy Shevchenko
Date: Sat Jun 03 2017 - 11:36:55 EST


On Sat, Jun 3, 2017 at 1:29 AM, Peter S. Housel <housel@xxxxxxx> wrote:
> An earlier change to this function (3bdae810721b) fixed a leak in the
> case of an unsuccessful call to brcmf_sdiod_buffrw(). However, the
> glom_skb buffer, used for emulating a scattering read, is never used
> or referenced after its contents are copied into the destination
> buffers, and therefore always needs to be freed by the end of the
> function.

> err = brcmf_sdiod_buffrw(sdiodev, SDIO_FUNC_2, false, addr,
> glom_skb);
> - if (err) {
> - brcmu_pkt_buf_free_skb(glom_skb);
> - goto done;
> - }
> -
> - skb_queue_walk(pktq, skb) {
> - memcpy(skb->data, glom_skb->data, skb->len);
> - skb_pull(glom_skb, skb->len);

> + if (!err) {

This is not so often in use type of pattern.

> + skb_queue_walk(pktq, skb) {
> + memcpy(skb->data, glom_skb->data, skb->len);
> + skb_pull(glom_skb, skb->len);
> + }
> }

> + brcmu_pkt_buf_free_skb(glom_skb);

Can we just add this one line instead or I'm missing something?

> } else
> err = brcmf_sdiod_sglist_rw(sdiodev, SDIO_FUNC_2, false, addr,
> pktq);



--
With Best Regards,
Andy Shevchenko