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,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,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 76BBFC28CC3 for ; Sat, 1 Jun 2019 13:22:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C30D2731E for ; Sat, 1 Jun 2019 13:22:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559395326; bh=BbOwVBE/a0Ts6qr8jzkK8ATWPK9HNWZdFgnN6gM9smM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bRY+FqEkMPqq3weuNeKiiJ/LAjA2BkCcwU5FWeluURFop6l10JMpsg3vV9y1V0jR6 2yeKtYLkCz3xL3+aKyZpdyTqmYlh9+EhpLMtoNuwuoz0DhlANEOTFGVgKdM7683ccR fh8JP8fSnDwxoL1J7BUwXOW7yQQ/3LvJDrVIsttg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728662AbfFANWF (ORCPT ); Sat, 1 Jun 2019 09:22:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:49510 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728112AbfFANWE (ORCPT ); Sat, 1 Jun 2019 09:22:04 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 314DB27312; Sat, 1 Jun 2019 13:22:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559395323; bh=BbOwVBE/a0Ts6qr8jzkK8ATWPK9HNWZdFgnN6gM9smM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Mb6ynkiRcuUzTT2BaV4VA5c0Tfxtiq0KY3CZB2zfOSXfx+K3jHdBd9kuJh1pVX62T V73wK0gTkOOnEPzIn1khG3Y+ruD5FxxTzinSNb2xrdRZQv6Ig2e05HfXNnIndGxP3D RlN/+CK0Ii1cWGlcPyxeQCLX5EiozwdbA8VqIv/U= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Christian Brauner , Luis Chamberlain , Kees Cook , Alexey Dobriyan , Al Viro , Dominik Brodowski , "Eric W. Biederman" , Joe Lawrence , Waiman Long , Andrew Morton , Linus Torvalds , Sasha Levin , linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 003/141] sysctl: return -EINVAL if val violates minmax Date: Sat, 1 Jun 2019 09:19:39 -0400 Message-Id: <20190601132158.25821-3-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190601132158.25821-1-sashal@kernel.org> References: <20190601132158.25821-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Christian Brauner [ Upstream commit e260ad01f0aa9e96b5386d5cd7184afd949dc457 ] Currently when userspace gives us a values that overflow e.g. file-max and other callers of __do_proc_doulongvec_minmax() we simply ignore the new value and leave the current value untouched. This can be problematic as it gives the illusion that the limit has indeed be bumped when in fact it failed. This commit makes sure to return EINVAL when an overflow is detected. Please note that this is a userspace facing change. Link: http://lkml.kernel.org/r/20190210203943.8227-4-christian@brauner.io Signed-off-by: Christian Brauner Acked-by: Luis Chamberlain Cc: Kees Cook Cc: Alexey Dobriyan Cc: Al Viro Cc: Dominik Brodowski Cc: "Eric W. Biederman" Cc: Joe Lawrence Cc: Waiman Long Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- kernel/sysctl.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 9a85c7ae73621..f8576509c7bef 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -2791,8 +2791,10 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int if (neg) continue; val = convmul * val / convdiv; - if ((min && val < *min) || (max && val > *max)) - continue; + if ((min && val < *min) || (max && val > *max)) { + err = -EINVAL; + break; + } *i = val; } else { val = convdiv * (*i) / convmul; -- 2.20.1