From: Andrew Morton <akpm@osdl.org>
To: linux-ia64@vger.kernel.org
Subject: Re: [RFC] prevent "dd if=/dev/mem" crash
Date: Fri, 17 Oct 2003 22:50:28 +0000 [thread overview]
Message-ID: <marc-linux-ia64-106643118916896@msgid-missing> (raw)
In-Reply-To: <marc-linux-ia64-106642876514553@msgid-missing>
Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:
>
> Old behavior:
>
> # dd if=/dev/mem of=/dev/null
> <unrecoverable machine check>
I recently fixed this for ia32 by changing copy_to_user() to not oops if
the source address generated a fault. Similarly copy_from_user() returns
an error if the destination generates a fault.
In other words: drivers/char/mem.c requires that the architecture's
copy_*_user() functions correctly handle faults on either the source or
dest of the copy.
next prev parent reply other threads:[~2003-10-17 22:50 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-10-17 22:10 [RFC] prevent "dd if=/dev/mem" crash Bjorn Helgaas
2003-10-17 22:19 ` Luck, Tony
2003-10-17 22:23 ` Matt Mackall
2003-10-17 22:40 ` Andreas Schwab
2003-10-17 22:50 ` Andrew Morton [this message]
2003-10-17 23:25 ` Bjorn Helgaas
2003-10-17 23:55 ` Andrew Morton
2003-10-18 0:15 ` William Lee Irwin III
2003-10-18 0:21 ` David Mosberger
2003-10-18 0:49 ` Andrew Morton
2003-10-18 1:31 ` Matt Chapman
2003-10-18 1:41 ` Andrew Morton
2003-10-18 1:48 ` David Mosberger
2003-10-18 2:01 ` Andrew Morton
2003-10-18 2:01 ` Matt Chapman
2003-10-19 11:25 ` Eric W. Biederman
2003-10-19 18:17 ` Pavel Machek
2003-10-19 19:01 ` William Lee Irwin III
2003-10-20 15:17 ` Bjorn Helgaas
2003-10-20 17:42 ` Bjorn Helgaas
2003-10-20 18:48 ` David Mosberger
2003-10-23 8:33 ` Martin Pool
2003-10-23 9:31 ` Zoltan Menyhart
2003-10-23 21:05 ` Bjorn Helgaas
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=marc-linux-ia64-106643118916896@msgid-missing \
--to=akpm@osdl.org \
--cc=linux-ia64@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox