From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-195729-1522173532-2-7690452208107439935 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1522173531; b=aUu6QdpoHReOnnyIZyaYOyd740W8YDcNKJ5DReWQ9k+kQmO phZ0oXe/RBIZmRvkPssYaAGnInFxYW4aKPUz8PPnoJ/UAj8xlniF1EwYB/fGzN0o HVpX3AeHeScM7vDZ7cS7V2yksnLWVHOnBJlNeWTLxY4yg6qZXM2FplZqO2PFOiKz wWJLMFJret3sEC7RCMksXx9Tgdqid91HaKywRN4+mApTOBPY0lFGMsOnRv8Bo6qe aEvF6obJiyFnFj7YMBPeW4J1P7gRLofvU83LRZ9oDp5WNaBVL3RRgqq1pYGf8tHP WdZrex5MZPcUFPGKEGTbohHw0k7JjB3PHYBmSyQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1522173531; bh=QfkhsSbC2ozTI2aSZVcOj/zGRP tLzYKl+NJi2po1Ov0=; b=KFfp641Ikvpkq4UHn2GEUHn95+tLuHMJZPA6YBkXKQ H8owxMUcS8md4cqeoaA0Y86TgNtDz2Zceo3YiHHNa5cKmNj4O8Z2/EAta4Nz7UdY IraMjF5vg9NELrtnEra11o7GmhTCjX8MV6H3f/eKk90JnJ1sFGi6kljkU2WSY8qn B4VmlhvAYZVuAO5fAJu5U9ZIdkfgnE11kTidKRpVJv2qRi5/PP2a9pNGtKz6J4De I9A1/yOm+ZZoP/jWfq0eUYYrdamYqqBWBvr/rlyqR3pYu76+Zo6kFGK7LFPw7Qi5 zOsowYYaHnyUhrs3rV9mVOxsb4qsZSIB6cMTgIi4pAPg== ARC-Authentication-Results: i=1; mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfDLFxkjcxTN0XN0zw8y2KFAZp0uKf8hREbKSVr/Whml29Wsh4jVI0SHFllOFo3075xOoIHGEMyuYKLjTdqUwGoa8R0//hr8Zip+6SQPkVzgmPK3ZiZnd zs/Gl6IxnLAol8aggJclwRoqm4NzdXK44+rgOKjxrGvl7PihG4XwmKITEm9w2Wxw3FIosBAtSDsQlwf3rKGJNfHDoR9CSznS4wE7grwVz5X7iP/KKvNvEaVt X-CM-Analysis: v=2.3 cv=Tq3Iegfh c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=IkcTkHD0fZMA:10 a=v2DPQv5-lfwA:10 a=1XWaLZrsAAAA:8 a=hWMQpYRtAAAA:8 a=ag1SF4gXAAAA:8 a=wSEHxrgEdzogoj8pM7IA:9 a=QEXdDO2ut3YA:10 a=KCsI-UfzjElwHeZNREa_:22 a=Yupwre4RP9_Eg_Bd0iYG:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753095AbeC0Qae (ORCPT ); Tue, 27 Mar 2018 12:30:34 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:41982 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753090AbeC0Qad (ORCPT ); Tue, 27 Mar 2018 12:30:33 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chenbo Feng , Lorenzo Colitti , Daniel Borkmann Subject: [PATCH 4.4 42/43] bpf: skip unnecessary capability check Date: Tue, 27 Mar 2018 18:27:46 +0200 Message-Id: <20180327162718.745862535@linuxfoundation.org> X-Mailer: git-send-email 2.16.3 In-Reply-To: <20180327162716.407986916@linuxfoundation.org> References: <20180327162716.407986916@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chenbo Feng commit 0fa4fe85f4724fff89b09741c437cbee9cf8b008 upstream. The current check statement in BPF syscall will do a capability check for CAP_SYS_ADMIN before checking sysctl_unprivileged_bpf_disabled. This code path will trigger unnecessary security hooks on capability checking and cause false alarms on unprivileged process trying to get CAP_SYS_ADMIN access. This can be resolved by simply switch the order of the statement and CAP_SYS_ADMIN is not required anyway if unprivileged bpf syscall is allowed. Signed-off-by: Chenbo Feng Acked-by: Lorenzo Colitti Signed-off-by: Daniel Borkmann Signed-off-by: Greg Kroah-Hartman --- kernel/bpf/syscall.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -673,7 +673,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf union bpf_attr attr = {}; int err; - if (!capable(CAP_SYS_ADMIN) && sysctl_unprivileged_bpf_disabled) + if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN)) return -EPERM; if (!access_ok(VERIFY_READ, uattr, 1))