Message-ID: <55C2AE7B.4040805@imgtec.com>
Date: Wed, 5 Aug 2015 17:46:51 -0700
From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
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To: David Daney <ddaney@caviumnetworks.com>
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Subject: Re: [PATCH v4 3/3] MIPS: set stack/data protection as non-executable
References: <20150805234348.20722.71740.stgit@ubuntu-yegoshin> <20150805234936.20722.60927.stgit@ubuntu-yegoshin> <20150805235543.GG2057@NP-P-BURTON> <55C2A50A.50805@imgtec.com> <55C2A6FE.1020003@caviumnetworks.com> <55C2A91B.1090704@imgtec.com> <55C2AC5B.50408@caviumnetworks.com>
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On 08/05/2015 05:37 PM, David Daney wrote:
> This just means that your userspace is broken.
>
> If GLibC cannot do the right thing then it should be fixed.

Let's skip this until you explain how to create a fully 
non-executable-stack process. GLIBC people is ready to do something but 
after we remove emulation from stack.

>
>
> You cannot change the default setting for executable stack just 
> because you have created a broken userspace.

Please give me at least one example, one existing application which 
would suffer.

I remember that people already wrote here that this kind of apps (which 
is based on eXecutable stack and doesn't announce it in PT_GNU_STACK) 
need to be eliminated.

>
> The ability of legacy userspace to continue functioning cannot be 
> sacrificed.
>

Not at any price.

However, this switch is a separate patch from others. It can be not 
applied or it can be applied, depending from prevailing mind - what is 
more significant, some (unknown) app or non-executable stack protection.

- Leonid.
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