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Subject: Re: [PATCH 3/5] exec: Remove recursion from search_binary_handler
To:     "Eric W. Biederman" <ebiederm@xmission.com>,
        linux-kernel@vger.kernel.org
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>, Jann Horn <jannh@google.com>,
        Kees Cook <keescook@chromium.org>,
        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>,
        Casey Schaufler <casey@schaufler-ca.com>,
        linux-security-module@vger.kernel.org,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        Andy Lutomirski <luto@amacapital.net>
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 <87eerszyim.fsf_-_@x220.int.ebiederm.org>
From:   Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Message-ID: <ee83587b-8a1c-3c4f-cc0f-7bc98afabae1@I-love.SAKURA.ne.jp>
Date:   Sun, 10 May 2020 13:22:37 +0900
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On 2020/05/10 4:41, Eric W. Biederman wrote:
> --- a/fs/binfmt_misc.c
> +++ b/fs/binfmt_misc.c
> @@ -234,10 +234,7 @@ static int load_misc_binary(struct linux_binprm *bprm)
>  	if (retval < 0)
>  		goto error;
>  
> -	retval = search_binary_handler(bprm);
> -	if (retval < 0)
> -		goto error;
> -
> +	retval = 1; /* Search for the interpreter */
>  ret:
>  	dput(fmt->dentry);
>  	return retval;

Wouldn't this change cause

	if (fd_binary > 0)
		ksys_close(fd_binary);
	bprm->interp_flags = 0;
	bprm->interp_data = 0;

not to be called when "Search for the interpreter" failed?