From patchwork Fri Sep 18 12:45:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11784821 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 266DE14F6 for ; Fri, 18 Sep 2020 12:46:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 00D4621D7B for ; Fri, 18 Sep 2020 12:46:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="sY+q9nG0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726796AbgIRMqC (ORCPT ); Fri, 18 Sep 2020 08:46:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39822 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726714AbgIRMpt (ORCPT ); Fri, 18 Sep 2020 08:45:49 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C586C061756; Fri, 18 Sep 2020 05:45:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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=JS63/rqkwUNTXwLowQfzdacfYjAtRcLXlr++78o/BT4=; b=sY+q9nG0cOiCMUx60dsbMGVPCz LVrYVhlOm2U0rDRkmCim2mpUjwSFA6xVzz7XwcQDo4SGRAVwynXQreWP6XBiVGi0g8W953f/N5oAl fMg12npyy16DCpLmH5VyXk669QwmnN85j6R0RkgK4f6gMcC3WoQ2pca3RMQOVsobTRfwuN1EThzdb jmGzqX9W6pU1MU4WfYmm+VGPkudgq8nJGWoYHdACNbyNatdhwXgx392LSabw4WcTao2KVrdLM7tlC iBsImmimlsk8J7PE28Q6ManmOx7kcJttWHAavkEleNAMRyHiwRuRenktDL1zD4kI4xDUsqKE4hm8M JLB9Xxjg==; Received: from [80.122.85.238] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kJFlk-0008T4-DQ; Fri, 18 Sep 2020 12:45:40 +0000 From: Christoph Hellwig To: Alexander Viro Cc: Andrew Morton , Jens Axboe , Arnd Bergmann , David Howells , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-kernel@vger.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-block@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, io-uring@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH 3/9] fs: explicitly check for CHECK_IOVEC_ONLY in rw_copy_check_uvector Date: Fri, 18 Sep 2020 14:45:27 +0200 Message-Id: <20200918124533.3487701-4-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200918124533.3487701-1-hch@lst.de> References: <20200918124533.3487701-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: Explicitly check for the magic value insted of implicitly relying on its number representation. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn --- fs/read_write.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 5db58b8c78d0dd..f153116bc5399b 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -840,8 +840,7 @@ ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, ret = -EINVAL; goto out; } - if (type >= 0 - && unlikely(!access_ok(buf, len))) { + if (type != CHECK_IOVEC_ONLY && unlikely(!access_ok(buf, len))) { ret = -EFAULT; goto out; } @@ -911,7 +910,7 @@ ssize_t compat_rw_copy_check_uvector(int type, } if (len < 0) /* size_t not fitting in compat_ssize_t .. */ goto out; - if (type >= 0 && + if (type != CHECK_IOVEC_ONLY && !access_ok(compat_ptr(buf), len)) { ret = -EFAULT; goto out;