my patches on busybox, 1/4: mount params on heap

[Sven Eisenberg (novero/Bochum)]

Hello busybox developers,

i send you some patches i did on busybox. Not all of them are meant to be included on master.
I will send a message for each patch, so in case there is discussion, the threads should not mix it up.

The first patch was a fix / workaround for a nasty problem we have seen.
The mount command in one of our ARM based, linux 2.6.31.14 based boards sporadically failed with EFAULT.
The linux kernels method exact_copy_from_user() which is exclusively used for the mount syscall handling, has a problem when the string is not page aligned. And for strings that are delivered as stack-pointer this is quite random. At least that was my interpretation of the problem and code.

I walked the easy path and work-arounded the problem by copying the parameters for the mount syscall to heap.

Regards, Sven Eisenberg


Sven Eisenberg
Advanced Development

Novero GmbH
Meesmannstr. 103 | 44807 Bochum | Germany
Sven.Eisenberg at novero.com<mailto:Sven.Eisenberg at novero.com> | www.novero.com<http://www.novero.com/>

Novero GmbH | Parsevalstr. 7a | 40468 Düsseldorf | Germany | Amtsgericht Düsseldorf | HRB 58283 | Umsatzsteueridentifikationsnummer: DE 814973142 | Geschäftsführer: Freddie Geier

A Laird business www.lairdtech.com<http://www.lairdtech.com/>

[Laird Logo Strapline.COLOR.CMYK.PNG]

Follow us:  [LinkedinEmail] <https://www.linkedin.com/company/laird-technologies>   [TwitterEmail] <https://twitter.com/LairdTech>   [fbemail] <https://www.facebook.com/lairdtech>    [youtube_24x24] <https://www.youtube.com/user/lairdtech>

THE INFORMATION CONTAINED IN THIS DOCUMENT IS OF A PROPRIETARY NATURE AND IS INTENDED TO BE KEPT CONFIDENTIAL BETWEEN THE SENDER AND THE INTENDED RECIPIENT. IT MAY NOT BE REPRODUCED OR USED WITHOUT EXPRESS WRITTEN PERMISSION OF LAIRD TECHNOLOGIES.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.busybox.net/pipermail/busybox/attachments/20160303/096c91bd/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 21354 bytes
Desc: image001.png
URL: <http://lists.busybox.net/pipermail/busybox/attachments/20160303/096c91bd/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 939 bytes
Desc: image002.jpg
URL: <http://lists.busybox.net/pipermail/busybox/attachments/20160303/096c91bd/attachment-0003.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.png
Type: image/png
Size: 1823 bytes
Desc: image003.png
URL: <http://lists.busybox.net/pipermail/busybox/attachments/20160303/096c91bd/attachment-0003.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image004.jpg
Type: image/jpeg
Size: 934 bytes
Desc: image004.jpg
URL: <http://lists.busybox.net/pipermail/busybox/attachments/20160303/096c91bd/attachment-0004.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image005.jpg
Type: image/jpeg
Size: 1003 bytes
Desc: image005.jpg
URL: <http://lists.busybox.net/pipermail/busybox/attachments/20160303/096c91bd/attachment-0005.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Allocate-mount-parameters-on-heap-instead-of-using-t.patch
Type: application/octet-stream
Size: 1906 bytes
Desc: 0001-Allocate-mount-parameters-on-heap-instead-of-using-t.patch
URL: <http://lists.busybox.net/pipermail/busybox/attachments/20160303/096c91bd/attachment-0001.obj>