linux-kernel - Re: [PATCH 5/8] lguest: trivial guest network driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 14 Feb 2007 15:47:55 +1100
From:	Rusty Russell <rusty@...tcorp.com.au>
To:	Herbert Xu <herbert@...dor.apana.org.au>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	lkml - Kernel Mailing List <linux-kernel@...r.kernel.org>,
	virtualization <virtualization@...ts.osdl.org>,
	jgarzik <jgarzik@...ox.com>
Subject: Re: [PATCH 5/8] lguest: trivial guest network driver

On Wed, 2007-02-14 at 01:06 +1100, Herbert Xu wrote:
> On Tue, Feb 13, 2007 at 01:15:18PM +1100, Rusty Russell wrote:
> > 
> > Good spotting!  This function needs to be passed skb_headlen(skb),
> > rather than skb->len.  Patch is below (I renamed the parameter as well,
> > for clarity).
> 
> How about just dropping that parameter and using skb_headlen(skb)
> directly?

It's also used to generate dma structs for outgoing packets.  In that
case, skb_headlen() == 0:

static struct sk_buff *lguestnet_alloc_skb(struct net_device *dev, int gfpflags)
{
	struct sk_buff *skb;

	skb = alloc_skb(16 + ETH_HLEN + DATA_SIZE, gfpflags);
	if (!skb)
		return NULL;

	skb->dev = dev;
	skb_reserve(skb, 16);
	return skb;
}

/* Find a new skb to put in this slot in shared mem. */
static int fill_slot(struct net_device *dev, unsigned int slot)
{
	struct lguestnet_info *info = dev->priv;
	/* Try to create and register a new one. */
	info->skb[slot] = lguestnet_alloc_skb(dev, GFP_ATOMIC);
	if (!info->skb[slot]) {
		printk("%s: could not fill slot %i\n", dev->name, slot);
		return -ENOMEM;
	}

	skb_to_dma(info->skb[slot], ETH_HLEN + DATA_SIZE, &info->dma[slot]);

Cheers,
Rusty.


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/