linux-kernel - Re: [PATCH v5 13/16] powerpc/mm/32s: Use BATs for STRICT_KERNEL

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1c271e47-6917-2f29-97b6-f3160ddf5117@c-s.fr>
Date:   Sun, 16 Jun 2019 10:01:10 +0200
From:   christophe leroy <christophe.leroy@....fr>
To:     Andreas Schwab <schwab@...ux-m68k.org>
Cc:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>, j.neuschaefer@....net,
        linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org
Subject: Re: [PATCH v5 13/16] powerpc/mm/32s: Use BATs for STRICT_KERNEL_RWX



Le 15/06/2019 à 14:28, Andreas Schwab a écrit :
> On Feb 21 2019, Christophe Leroy <christophe.leroy@....fr> wrote:
> 
>> diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
>> index a000768a5cc9..6e56a6240bfa 100644
>> --- a/arch/powerpc/mm/pgtable_32.c
>> +++ b/arch/powerpc/mm/pgtable_32.c
>> @@ -353,7 +353,10 @@ void mark_initmem_nx(void)
>>   	unsigned long numpages = PFN_UP((unsigned long)_einittext) -
>>   				 PFN_DOWN((unsigned long)_sinittext);
>>   
>> -	change_page_attr(page, numpages, PAGE_KERNEL);
>> +	if (v_block_mapped((unsigned long)_stext) + 1)
> 
> That is always true.
> 

Did you boot with 'nobats' kernel parameter ?

If not, that's normal to be true, it means that memory is mapped with BATs.

When you boot with 'nobats' parameter, this should return false.

Christophe

---
L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.
https://www.avast.com/antivirus