From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE0E1C43387 for ; Thu, 27 Dec 2018 11:19:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9CCA4218E2 for ; Thu, 27 Dec 2018 11:19:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=bewilderbeest.net header.i=@bewilderbeest.net header.b="fZWrTJBY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730847AbeL0LT1 (ORCPT ); Thu, 27 Dec 2018 06:19:27 -0500 Received: from thorn.bewilderbeest.net ([71.19.156.171]:41796 "EHLO thorn.bewilderbeest.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729424AbeL0LT0 (ORCPT ); Thu, 27 Dec 2018 06:19:26 -0500 X-Greylist: delayed 356 seconds by postgrey-1.27 at vger.kernel.org; Thu, 27 Dec 2018 06:19:26 EST Received: from hatter.bewilderbeest.net (hatter.bewilderbeest.net [IPv6:2001:470:c3f4:1::1:1]) (using TLSv1.2 with cipher DHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: zev) by thorn.bewilderbeest.net (Postfix) with ESMTPSA id 752F680535; Thu, 27 Dec 2018 03:13:52 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 thorn.bewilderbeest.net 752F680535 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bewilderbeest.net; s=thorn; t=1545909232; bh=gWq089DtpuWYsmHQ7Id1gtor1jZkWB/dGshv8w5ykwo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fZWrTJBYio7h6LHaTfsXIhsF0SVhiH0XpLa0vuxP6nzbJF4lY0/Iv0b3RNGmZtrwO rMGsFjZUq5O413HwJDgiZE4Khb7CGYIims2N5S/3Meee+2kLfy5fXs4bTia38XCepK S9LvkomWYzLSwJrBhbfHElpfrX3SLBEuxPx5B6g8= From: Zev Weiss To: Luis Chamberlain , Kees Cook Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Zev Weiss Subject: [PATCH 2/2] kernel/sysctl.c: define minmax conv functions in terms of non-minmax versions Date: Thu, 27 Dec 2018 05:12:30 -0600 Message-Id: <20181227111231.12912-3-zev@bewilderbeest.net> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20181227111231.12912-1-zev@bewilderbeest.net> References: <20181227111231.12912-1-zev@bewilderbeest.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org do_proc_do[u]intvec_minmax_conv() had included open-coded versions of do_proc_do[u]intvec_conv(), though the signed one omitted the check that the value is in [INT_MIN, INT_MAX]. Rather than increase the duplication further by copying the additional check, we can instead refactor both to be defined in terms of their non-bounded counterparts (plus the added check). Signed-off-by: Zev Weiss --- kernel/sysctl.c | 50 ++++++++++++++++++++++++++----------------------- 1 file changed, 27 insertions(+), 23 deletions(-) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 5fc724e4e454..4a0261d32401 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -2562,23 +2562,26 @@ static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp, int *valp, int write, void *data) { + int tmp, ret; struct do_proc_dointvec_minmax_conv_param *param = data; + + /* + * First write to a temporary local int so we can bounds-check it + * before touching *valp. + */ + int *ip = write ? &tmp : valp; + + ret = do_proc_dointvec_conv(negp, lvalp, ip, write, data); + if (ret) + return ret; + if (write) { - int val = *negp ? -*lvalp : *lvalp; - if ((param->min && *param->min > val) || - (param->max && *param->max < val)) + if ((param->min && *param->min > tmp) || + (param->max && *param->max < tmp)) return -EINVAL; - *valp = val; - } else { - int val = *valp; - if (val < 0) { - *negp = true; - *lvalp = -(unsigned long)val; - } else { - *negp = false; - *lvalp = (unsigned long)val; - } + *valp = tmp; } + return 0; } @@ -2627,22 +2630,23 @@ static int do_proc_douintvec_minmax_conv(unsigned long *lvalp, unsigned int *valp, int write, void *data) { + int ret; + unsigned int tmp; struct do_proc_douintvec_minmax_conv_param *param = data; - if (write) { - unsigned int val = *lvalp; + /* write via temporary local uint for bounds-checking */ + unsigned int *up = write ? &tmp : valp; - if (*lvalp > UINT_MAX) - return -EINVAL; + ret = do_proc_douintvec_conv(lvalp, up, write, data); + if (ret) + return ret; - if ((param->min && *param->min > val) || - (param->max && *param->max < val)) + if (write) { + if ((param->min && *param->min > tmp) || + (param->max && *param->max < tmp)) return -ERANGE; - *valp = val; - } else { - unsigned int val = *valp; - *lvalp = (unsigned long) val; + *valp = tmp; } return 0; -- 2.20.1