netdev - RE: [PATCH 3/4] lib/hexdump.c: Replace ascii bool in hex_dump_to

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:   Mon, 15 Apr 2019 11:03:57 +0000
From:   David Laight <David.Laight@...LAB.COM>
To:     'Alastair D'Silva' <alastair@...ilva.org>,
        'Petr Mladek' <pmladek@...e.com>
CC:     'Alastair D'Silva' <alastair@....ibm.com>,
        'Jani Nikula' <jani.nikula@...ux.intel.com>,
        'Joonas Lahtinen' <joonas.lahtinen@...ux.intel.com>,
        'Rodrigo Vivi' <rodrigo.vivi@...el.com>,
        'David Airlie' <airlied@...ux.ie>,
        'Daniel Vetter' <daniel@...ll.ch>,
        'Karsten Keil' <isdn@...ux-pingi.de>,
        'Jassi Brar' <jassisinghbrar@...il.com>,
        'Tom Lendacky' <thomas.lendacky@....com>,
        "'David S. Miller'" <davem@...emloft.net>,
        'Jose Abreu' <Jose.Abreu@...opsys.com>,
        'Kalle Valo' <kvalo@...eaurora.org>,
        'Stanislaw Gruszka' <sgruszka@...hat.com>,
        'Benson Leung' <bleung@...omium.org>,
        "'Enric Balletbo i Serra'" <enric.balletbo@...labora.com>,
        "'James E.J. Bottomley'" <jejb@...ux.ibm.com>,
        "'Martin K. Petersen'" <martin.petersen@...cle.com>,
        'Greg Kroah-Hartman' <gregkh@...uxfoundation.org>,
        'Alexander Viro' <viro@...iv.linux.org.uk>,
        'Sergey Senozhatsky' <sergey.senozhatsky@...il.com>,
        'Steven Rostedt' <rostedt@...dmis.org>,
        'Andrew Morton' <akpm@...ux-foundation.org>,
        "intel-gfx@...ts.freedesktop.org" <intel-gfx@...ts.freedesktop.org>,
        "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "ath10k@...ts.infradead.org" <ath10k@...ts.infradead.org>,
        "linux-wireless@...r.kernel.org" <linux-wireless@...r.kernel.org>,
        "linux-scsi@...r.kernel.org" <linux-scsi@...r.kernel.org>,
        "linux-fbdev@...r.kernel.org" <linux-fbdev@...r.kernel.org>,
        "devel@...verdev.osuosl.org" <devel@...verdev.osuosl.org>,
        "linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>
Subject: RE: [PATCH 3/4] lib/hexdump.c: Replace ascii bool in
 hex_dump_to_buffer with flags

From: Alastair D'Silva
> Sent: 15 April 2019 11:45
...
> > Although I think you'd want a 'no hex' flag to suppress the hex.
> >
> > Probably more useful flags are ones to suppress the address column.
> 
> This is already supported by the prefix_type parameter - are you proposing that we eliminate the
> parameter & combine it with flags?

I was looking at the flags on one of my hexdump() functions...

> > I've also used flags to enable (or disable) suppression of multiple lines of
> > zeros of constant bytes.
> > In that case you may want hexdump to return the flags for the next call when
> > a large buffer is being dumped in fragments.
> 
> I'm afraid I don't quite follow here, hex_dump_to_buffer doesn't alter the flags,
> so the caller already knows it.

If you are suppressing lines of zeros and dumping a buffer in several blocks
then subsequent calls need to know that the last line of the previous call
was suppressed zeros - and carry on with the same suppressed block.

I've not looked to see if it does support suppressing lines of zeros/0xff.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)