netdev - Re: [PATCH] skbuff: make skb_put

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:   Thu, 15 Jun 2017 15:30:58 -0700
From:   Joe Perches <joe@...ches.com>
To:     Johannes Berg <johannes@...solutions.net>,
        David Miller <davem@...emloft.net>
Cc:     netdev@...r.kernel.org
Subject: Re: [PATCH] skbuff: make skb_put_zero() return void

On Fri, 2017-06-16 at 00:21 +0200, Johannes Berg wrote:
> On Thu, 2017-06-15 at 15:17 -0700, Joe Perches wrote:
> 
> > I suggest changing those to skb_put_char(skb, char)
> 
> That might be something to think of, but you can't really know for sure
> that they're not using len > 1 and don't yet care about the other bytes
> or something. That'd probably be another bug, but ... dunno
> 
> And anyway, I think
> 
> *(u8 *)skb_put(skb, 1) = c;
> 
> isn't really that bad. Obviously that could be converted further to
> skb_put_char(), using a simple spatch:
> 
> @@
> expression SKB, C;
> @@
> - *(u8 *)skb_put(SKB, 1) = C;
> + skb_put_char(SKB, C);
> 
> 
> > Here's a script that does the conversion.
> > 
> > $ /usr/bin/git grep -P --name-only
> > "\*\s*skb_put\s*\(\s*([\w\.\[\]\>\-]+)\s*,\s*1\s*\)\s*=\s*([^;]+);" |
> > \
> >   xargs perl -p -i -e 's/\*\s*skb_put\s*\(\s*([\w\.\[\]\>\-
> > ]+)\s*,\s*1\s*\)\s*=\s*([^;]+);/skb_put_char(\1, \2);/'
> 
> Uh, I think you're using the wrong tool for the job :-)

I'm familiar with both.

It depends on how much you want to wait.

The thing I wrote finished in about 2 seconds
on my little laptop.

cheers, Joe