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Date:   Tue, 5 May 2020 13:45:17 -0700
From:   Kees Cook <keescook@chromium.org>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     linux-kernel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>, Jann Horn <jannh@google.com>,
        Greg Ungerer <gerg@linux-m68k.org>,
        Rob Landley <rob@landley.net>,
        Bernd Edlinger <bernd.edlinger@hotmail.de>,
        linux-fsdevel@vger.kernel.org, Al Viro <viro@ZenIV.linux.org.uk>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 1/7] binfmt: Move install_exec_creds after setup_new_exec
 to match binfmt_elf
Message-ID: <202005051345.8280CC0E@keescook>
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On Tue, May 05, 2020 at 02:41:01PM -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.
> 
> The binfmt_flagt bits were tested by Greg Ungerer <gerg@linux-m68k.org>
> 
> Ref: 9f834ec18def ("binfmt_elf: switch to new creds when switching to new mm")
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook