lkml.org 
[lkml]   [2004]   [Dec]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Coverity] Untrusted user data in kernel
linux-os wrote:
> On Fri, 17 Dec 2004, Bill Davidsen wrote:
>
>> James Morris wrote:
>>
>>> On Fri, 17 Dec 2004, Patrick McHardy wrote:
>>>
>>> That's what I meant, you need the capability to do anything bad :-)
>>
>>
>> Are you saying that processes with capability don't make mistakes?
>> This isn't a bug related to untrusted users doing privileged
>> operations, it's a case of using unchecked user data.
>>
>
> But isn't there always the possibility of "unchecked user data"?
> I can, as root, do `cp /dev/zero /dev/mem` and have the most
> spectacular crask you've evet seen. I can even make my file-
> systems unrecoverable.
>

But the difference between you example (cp /dev/zero /dev/mem) and
passing unchecked data to the kernel is... you _can_ check the data and
do something about it if you discover that the data is not valid/within
a range/whatever even if the user has full permissions.
No same person would do a 'cp /dev/zero /dev/mem', but passing bad data
is more likely to happen, badly written userspace configuration tools etc.

tom
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:08    [from the cache]
©2003-2011 Jasper Spaans