From patchwork Thu Jun 18 14:46:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11612413 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2F6B614E3 for ; Thu, 18 Jun 2020 14:47:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1714420C09 for ; Thu, 18 Jun 2020 14:47:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="iYAJJP5d" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730885AbgFROrL (ORCPT ); Thu, 18 Jun 2020 10:47:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731024AbgFROq5 (ORCPT ); Thu, 18 Jun 2020 10:46:57 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6524C06174E; Thu, 18 Jun 2020 07:46:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=6JtQFSFZNuHNYVW/hbRiOl0cmjzNgKOe7nvuIEAqZOM=; b=iYAJJP5dv671OjlYmO+jCGYm7V obHfCgXEmlKduw1i0rWhbJV9lFULLEgzb9E6mscVceQe8UOeQNgA+zaR1S6HwcYVowGJPA+25JCKu jUgM6t15RIfx8rl0ZPe0HUXoj7keKsSc12QCKituahyN+zagsuFt9e1fYIBFo8hpTvZAahF8zZ2df x/6sWF1uM9BQVUd65Ek6YWo27Nu0JwoaAuwOmo1Yokr6Z2DAUpnrxtHHFz/uSbu6vU0DbzCTDDANY Ph3s7UCh38TSmta7V3xnGJAKez48xuf8YKhUtEmWcLYs2XB4P5d0kkPG51I0Nlgtu1frDsqhFPdig wyMznnQA==; Received: from 195-192-102-148.dyn.cablelink.at ([195.192.102.148] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jlvoQ-0006Ri-Ld; Thu, 18 Jun 2020 14:46:43 +0000 From: Christoph Hellwig To: Al Viro Cc: Arnd Bergmann , Brian Gerst , Luis Chamberlain , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/6] exec: split prepare_arg_pages Date: Thu, 18 Jun 2020 16:46:25 +0200 Message-Id: <20200618144627.114057-5-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200618144627.114057-1-hch@lst.de> References: <20200618144627.114057-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Move counting the arguments and enviroment variables out of prepare_arg_pages and rename the rest of the function to check_arg_limit. This prepares for a version of do_execvat that takes kernel pointers. Signed-off-by: Christoph Hellwig --- fs/exec.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index a5d91f8b1341d5..34781db6bf6889 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -435,20 +435,10 @@ static int count_strings(const char __user *const __user *argv) return i; } -static int prepare_arg_pages(struct linux_binprm *bprm, - const char __user *const __user *argv, - const char __user *const __user *envp) +static int check_arg_limit(struct linux_binprm *bprm) { unsigned long limit, ptr_size; - bprm->argc = count_strings(argv); - if (bprm->argc < 0) - return bprm->argc; - - bprm->envc = count_strings(envp); - if (bprm->envc < 0) - return bprm->envc; - /* * Limit to 1/4 of the max stack size or 3/4 of _STK_LIM * (whichever is smaller) for the argv+env strings. @@ -1886,7 +1876,19 @@ int do_execveat(int fd, struct filename *filename, if (retval) goto out_unmark; - retval = prepare_arg_pages(bprm, argv, envp); + bprm->argc = count_strings(argv); + if (bprm->argc < 0) { + retval = bprm->argc; + goto out; + } + + bprm->envc = count_strings(envp); + if (bprm->envc < 0) { + retval = bprm->envc; + goto out; + } + + retval = check_arg_limit(bprm); if (retval < 0) goto out;