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Date:   Tue, 5 May 2020 13:46:56 -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 2/7] exec: Make unlocking exec_update_mutex explict
Message-ID: <202005051346.B4752035A1@keescook>
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On Tue, May 05, 2020 at 02:41:47PM -0500, Eric W. Biederman wrote:
> 
> With install_exec_creds updated to follow immediately after
> setup_new_exec, the failure of unshare_sighand is the only
> code path where exec_update_mutex is held but not explicitly
> unlocked.
> 
> Update that code path to explicitly unlock exec_update_mutex.
> 
> Remove the unlocking of exec_update_mutex from free_bprm.
> 
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

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

-- 
Kees Cook