The Linux Kernel Mailing List
 help / color / mirror / Atom feed
From: David Miller <davem@davemloft.net>
To: m.kozlowski@tuxland.pl
Cc: hadi@cyberus.ca, netdev@vger.kernel.org, jeff@garzik.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: ifb error path loop fix
Date: Mon, 01 Jan 2007 23:51:32 -0800 (PST)	[thread overview]
Message-ID: <20070101.235132.85409619.davem@davemloft.net> (raw)
In-Reply-To: <200701020055.51805.m.kozlowski@tuxland.pl>

From: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Date: Tue, 2 Jan 2007 00:55:51 +0100

> On error we should start freeing resources at [i-1] not [i-2].
> 
> Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>

Patch applied, thanks Mariusz.

> diff -upr linux-2.6.20-rc2-mm1-a/drivers/net/ifb.c linux-2.6.20-rc2-mm1-b/drivers/net/ifb.c
> --- linux-2.6.20-rc2-mm1-a/drivers/net/ifb.c	2006-12-24 05:00:32.000000000 +0100
> +++ linux-2.6.20-rc2-mm1-b/drivers/net/ifb.c	2007-01-02 00:25:34.000000000 +0100
> @@ -271,8 +271,7 @@ static int __init ifb_init_module(void)
>  	for (i = 0; i < numifbs && !err; i++)
>  		err = ifb_init_one(i);
>  	if (err) {
> -		i--;
> -		while (--i >= 0)
> +		while (i--)
>  			ifb_free_one(i);
>  	}

One could argue from a defensive programming perspective that
this bug comes from the fact that the ifb_init_one() loop
advances state before checking for errors ('i' is advanced before
the 'err' check due to the loop construct), and that's why the
error recovery code had to be coded specially :-)

Anyways, your fix is of course fine and I've applied it.

  reply	other threads:[~2007-01-02  7:51 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-01-01 23:55 [PATCH] net: ifb error path loop fix Mariusz Kozlowski
2007-01-02  7:51 ` David Miller [this message]
2007-01-02 10:30   ` Jarek Poplawski
2007-01-02 10:49   ` Mariusz Kozlowski
2007-01-02 23:20     ` David Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20070101.235132.85409619.davem@davemloft.net \
    --to=davem@davemloft.net \
    --cc=hadi@cyberus.ca \
    --cc=jeff@garzik.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=m.kozlowski@tuxland.pl \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox