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Date:   Tue, 7 Apr 2020 18:11:05 +0200
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Bernd Edlinger <bernd.edlinger@hotmail.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Alexey Gladkov <gladkov.alexey@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Kees Cook <keescook@chromium.org>, Jann Horn <jannh@google.com>
Subject: Re: [PATCH 1/3] binfmt: Move install_exec_creds after setup_new_exec
 to match binfmt_elf
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On Mon, Apr 06, 2020 at 08:31:25PM -0500, Eric W. Biederman wrote:
> 
> In 2016 Linus moved install_exec_creds immediately after
> setup_new_exec, in binfmt_elf as a cleanup and as part of closing a
> potential information leak.
> 
> Perform the same cleanup for the other binary formats.
> 
> Different binary formats doing the same things the same way makes exec
> easier to reason about and easier to maintain.
> 
> Putting install_exec_creds immediate after setup_new_exec makes many
> simplifications possible in the code.
> 
> Ref: 9f834ec18def ("binfmt_elf: switch to new creds when switching to new mm")
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Sure, why not.
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>