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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 7BA48C433DF for ; Wed, 20 May 2020 12:56:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B5882070A for ; Wed, 20 May 2020 12:56:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="FcM3iKpm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726805AbgETM4Z (ORCPT ); Wed, 20 May 2020 08:56:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726748AbgETM4Y (ORCPT ); Wed, 20 May 2020 08:56:24 -0400 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B86C0C061A0E for ; Wed, 20 May 2020 05:56:23 -0700 (PDT) Received: by mail-wr1-x444.google.com with SMTP id s8so3011270wrt.9 for ; Wed, 20 May 2020 05:56:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FRf0IXb8hQkrdaL1fqV3l4f1s2bF25mDJk/8LzKBDyk=; b=FcM3iKpmGOIcheIq2sv7UBjccYXgY5UfnFjB4xNjwyYn/tsB62nOO1DlESb5YDOJW0 sqFXADpYAoyt8FhrnVZr8S0nV8jXbRhFgVllGSXhkdtwDwjB2N1piQYgke2bBl7yz4Cu VYa9mPs5vM6n6ad8Zc7RtsTFPTTusIOL3Oj7Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=FRf0IXb8hQkrdaL1fqV3l4f1s2bF25mDJk/8LzKBDyk=; b=G/JBR3O9HSN2NQIUFXateLJco+Wp/rlrTZ+zmQ+XPRG6mSYlbTmtFi7MCjBYUOpNJt gfC4qrNEooZn48iUZLAbL2jSrpINE+IV1Hp36+/ms/GbKqmpx9AtHU6MK9ZEtTxwfBtk SbhNBTTcYi/+HT4TTJr9yZ9GTEX2TbapgZzQcgIqi2DSqf6sXKWuXMGsQrTtrOwy5gZt X6g/2aRcZ2QUGUrIE0apkasQmntCyNKUYgwMtq7kA+hTIxPqL1uQrTOaI6HxH/7KM7sE UXEZzT/2r5uiJGqX3QmgM8Kv2O+C96N1O21KRk9of6BeIxiUSAPYzaZl/dD97WXjZjwT pKwg== X-Gm-Message-State: AOAM530eCmCrcUOhkQW32iPKPuCfOMpR71iRwemsDqTT1z8wN7m23Eaz 5dZ7WIBYttk2jlbNVdFgfnMFbQ== X-Google-Smtp-Source: ABdhPJzZTIkt68m48X0Gd2mSWXMTScvuAo6k7MEMXpKVIa3O8ND+TYDMoHIr5dtTngUw3l1H6DOPPg== X-Received: by 2002:adf:e703:: with SMTP id c3mr4169330wrm.252.1589979382402; Wed, 20 May 2020 05:56:22 -0700 (PDT) Received: from kpsingh.zrh.corp.google.com ([81.6.44.51]) by smtp.gmail.com with ESMTPSA id i11sm2961978wrc.35.2020.05.20.05.56.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 May 2020 05:56:21 -0700 (PDT) From: KP Singh To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-security-module@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , James Morris , Anders Roxell , Casey Schaufler Subject: [PATCH bpf] security: Fix hook iteration for secid_to_secctx Date: Wed, 20 May 2020 14:56:16 +0200 Message-Id: <20200520125616.193765-1-kpsingh@chromium.org> X-Mailer: git-send-email 2.26.2.761.g0e0b3e54be-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: KP Singh secid_to_secctx is not stackable, and since the BPF LSM registers this hook by default, the call_int_hook logic is not suitable which "bails-on-fail" and casues issues when other LSMs register this hook and eventually breaks Audit. In order to fix this, directly iterate over the security hooks instead of using call_int_hook as suggested in: https: //lore.kernel.org/bpf/9d0eb6c6-803a-ff3a-5603-9ad6d9edfc00@schaufler-ca.com/#t Fixes: 98e828a0650f ("security: Refactor declaration of LSM hooks") Fixes: 625236ba3832 ("security: Fix the default value of secid_to_secctx hook" Reported-by: Alexei Starovoitov Signed-off-by: KP Singh --- security/security.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/security/security.c b/security/security.c index 7fed24b9d57e..51de970fbb1e 100644 --- a/security/security.c +++ b/security/security.c @@ -1965,8 +1965,20 @@ EXPORT_SYMBOL(security_ismaclabel); int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { - return call_int_hook(secid_to_secctx, -EOPNOTSUPP, secid, secdata, - seclen); + struct security_hook_list *hp; + int rc; + + /* + * Currently, only one LSM can implement secid_to_secctx (i.e this + * LSM hook is not "stackable"). + */ + hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) { + rc = hp->hook.secid_to_secctx(secid, secdata, seclen); + if (rc != LSM_RET_DEFAULT(secid_to_secctx)) + return rc; + } + + return LSM_RET_DEFAULT(secid_to_secctx); } EXPORT_SYMBOL(security_secid_to_secctx); -- 2.26.2.761.g0e0b3e54be-goog