lkml.org 
[lkml]   [2015]   [Aug]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [x86] copy_from{to}_user question
From
Date

> On Aug 14, 2015, at 00:43, Borislav Petkov <bp@suse.de> wrote:
>
> On Thu, Aug 13, 2015 at 06:04:54PM +0800, yalin wang wrote:
>> we store type into one fix register, for example r12 ,
>> then in fix up code, we can know the exception is caused by copy_from
>> copy_to or copy_in user function by check r12 value(0 , 1 ,2 value), then if
>> it is copy_from, we only allow read fault, if the exception is write fault, panic() .
>>
>> the same rules also apply to copy_to / copy_in function .
>>
>> is it possible to change it like this ?
>
> ... and we'll do all that jumping through hoops to fix what actual,
> real-life problem exactly?
i just want the x86 copy_from{to,in}_user() function have
the same behaviour as other platforms.
and can disclose potential BUGs in kernel, if do like this.

Thanks.



\
 
 \ /
  Last update: 2015-08-17 05:41    [W:0.075 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site