netdev - Re: [RFC] breakage in sysfs_readdir() and s

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]

Message-ID: <BANLkTi=AfYH1eg_O1N2M9BfcF=UmBFPy6w@mail.gmail.com>
Date:	Sun, 12 Jun 2011 10:59:42 -0700
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	"Eric W. Biederman" <ebiederm@...ssion.com>
Cc:	Al Viro <viro@...iv.linux.org.uk>, linux-fsdevel@...r.kernel.org,
	netdev@...r.kernel.org,
	Linux Containers <containers@...ts.osdl.org>
Subject: Re: [RFC] breakage in sysfs_readdir() and s_instances abuse in sysfs

On Sun, Jun 12, 2011 at 12:15 AM, Eric W. Biederman
<ebiederm@...ssion.com> wrote:
>
> I honestly hate the pattern that is being used here.  Holding a
> reference count because we can't be bothered to free things reliably
> when we actually stop using them.

WHAT?

That's what a reference count *is*. It's all about "free things
reliably when we actually stop using them".

Your comment makes zero sense.

EVERY SINGLE kernel data structure should be reference counted. Read
Documentation/CodingStyle, or look at any of the good code in the
kernel (ie core process or VFS code). A non-refcounted data structure
that is used by more than one entity IS A BUG!

Quite frankly, your objection sounds moronic. If there is more than
one user, then a reference count is _always_ the right thing. Nothing
else ever works, and trust me, people have tried. They've tried
locking, they've tried luck, they've tried crazy things. Nothing but
refcounts works.

                           Linus
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html