linux-kernel - Re: [PATCH] docs: add extra integer types to printk-formats

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: <e244390e3d245c94d6d2fb036943e63111ada86d.camel@perches.com>
Date:   Tue, 05 Mar 2019 11:59:30 -0800
From:   Joe Perches <joe@...ches.com>
To:     Nick Desaulniers <ndesaulniers@...gle.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Cc:     Louis Taylor <louis@...gniz.eu>, Jonathan Corbet <corbet@....net>,
        pmladek@...e.com, geert+renesas@...der.be,
        linux-doc@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>,
        clang-built-linux@...glegroups.com,
        Jon Flatley <jflat@...omium.org>
Subject: Re: [PATCH] docs: add extra integer types to printk-formats

On Mon, 2019-03-04 at 09:59 -0800, Nick Desaulniers wrote:
> On Sun, Mar 3, 2019 at 12:10 PM Andy Shevchenko
> <andriy.shevchenko@...ux.intel.com> wrote:
> > On Sun, Mar 03, 2019 at 12:36:47PM +0000, Louis Taylor wrote:
> > > A few commonly used integer types were absent from this table, so add
> > > them.
> > 
> > I'm not against the patch, but isn't obvious by reading POSIX and / or man
> > printf(3)?
> 
> You'd think; but based on the sheer number of -Wformat warnings
> (~450), I'm not so sure.

<shrug>  software defects are always present.

Many of the -Wformat warnings are bogus too.

There's nothing wrong with using %x for a unsigned int
of less than long size. (u8/u16)

>   At least with this patch they're "above the
> fold."

I'd personally go with
"posix plus kernel specific deletions and extensions"

> The kernel also has its own format flag extensions, and does not
> implement %n (for good reason), so it's better to be explicit than
> imply posix or glibc compat.

%i is also supported and used a few hundred times