Re: old buffer overflow in moxa driver

[Jiri Slaby <jirislaby@gmail.com>]

Alan Cox napsal(a):
>>   I noticed that the moxa input checking security bug described by
>> CVE-2005-0504 appears to remain unfixed upstream.
>>  
>> The issue is described here:
>>   http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2005-0504
>>
>> Debian has been shipping the following patch from Andres Salomon. I
>> tried contacting the listed maintainer a few months ago but received
>> no response.
> 
> 
>        case MOXA_LOAD_BIOS:
>         case MOXA_FIND_BOARD:
>         case MOXA_LOAD_C320B:
>         case MOXA_LOAD_CODE:
>                 if (!capable(CAP_SYS_RAWIO))
>                         return -EPERM;
>                 break;
> 
> At the point you abuse these calls you can already just load arbitary
> data from userspace anyway.

The problem is that we BUG_ON, when len < 0 in copy_from_user which is unlikely
something we want to cause?

regards,
-- 
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
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