linux-kernel - Re: [PATCH v2 1/5] firmware: fix _

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: <CA+55aFwSQqkA_yzvePe7p-aJkbVJc9od=wLvXvs9B=NcckFfoA@mail.gmail.com>
Date:	Tue, 12 May 2015 13:31:58 -0700
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	"Luis R. Rodriguez" <mcgrof@...not-panic.com>
Cc:	Ming Lei <ming.lei@...onical.com>,
	Rusty Russell <rusty@...tcorp.com.au>,
	David Howells <dhowells@...hat.com>,
	Seth Forshee <seth.forshee@...onical.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Paul Bolle <pebolle@...cali.nl>,
	Linux Wireless List <linux-wireless@...r.kernel.org>,
	"Luis R. Rodriguez" <mcgrof@...e.com>,
	Kyle McMartin <kyle@...nel.org>
Subject: Re: [PATCH v2 1/5] firmware: fix __getname() missing failure check

On Tue, May 12, 2015 at 11:30 AM, Luis R. Rodriguez
<mcgrof@...not-panic.com> wrote:
> +
> +       path = __getname();
> +       if (unlikely(!path))
> +               return PTR_ERR(path);

This makes no sense.

PTR_ERR() on NULL is an insane operation. It's a very non-intuitive
and misleading way of writing "0".

So not only is that "return 0;", that's not likely what you want _anyway_.

If you intended to return an error, you should just have done so, eg

        if (unlikely(!path))
                return -ENOMEM;

which actually does something sane, and is more readable.

PTR_ERR() is for when you get an error pointer, so a sequence like

        if (IS_ERR(ptr))
                return PTR_ERR(ptr);

is sensible (it checks whether the ptr has an error value in it, and
then returns the integer error value of the pointer).

But for a NULL pointer? No.

                       Linus
--
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/