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Date:   Thu, 17 Nov 2022 14:58:19 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
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Subject: Re: [PATCH mm-unstable v1 20/20] mm: rename FOLL_FORCE to FOLL_PTRACE
Message-ID: <202211171439.CDE720EAD@keescook>
References: <20221116102659.70287-1-david@redhat.com>
 <20221116102659.70287-21-david@redhat.com>
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On Wed, Nov 16, 2022 at 10:16:34AM -0800, Linus Torvalds wrote:
> There _are_ also small random cases too, like get_cmdline(). Maybe
> that counts as ptrace, but the execve() case most definitely does not.

Oh, er, why does get_arg_page() even need FOLL_FORCE? This is writing the
new stack contents to the nascent brpm->vma, which was newly allocated
with VM_STACK_FLAGS, which an arch can override, but they all appear to include
VM_WRITE | VM_MAYWRITE.

-- 
Kees Cook