From patchwork Sat Jun 27 13:20:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Guy Briggs X-Patchwork-Id: 216979 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=-7.1 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 autolearn=unavailable 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 AC9C4C433DF for ; Sat, 27 Jun 2020 13:23:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81EB4208B6 for ; Sat, 27 Jun 2020 13:23:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="M2dos+qS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726949AbgF0NXv (ORCPT ); Sat, 27 Jun 2020 09:23:51 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:53432 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726553AbgF0NXs (ORCPT ); Sat, 27 Jun 2020 09:23:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593264226; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:in-reply-to:in-reply-to:in-reply-to: references:references:references; bh=xHQ23E0ubwuEGdr08pTjn1ZZAxTi7f5b6ScMm0bJY4c=; b=M2dos+qSdkdfThdqEhDIKsZdSRpUlnleRLz5SSLKDmUuScAOxPdi2rNPySNeARJxGC++JK f87tLOdac2N1CSd3wVCCz7mBf3JyzO1/VTTla2k7/UaFtdNA2jDWgl5RegxJyr4gyBbrSH MI5gyle//eXIEsAQ8PIP1qEdX0c4uc4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-18-UOKJWxGZPmy5N6uVApuoTQ-1; Sat, 27 Jun 2020 09:23:44 -0400 X-MC-Unique: UOKJWxGZPmy5N6uVApuoTQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DFCF2800C60; Sat, 27 Jun 2020 13:23:42 +0000 (UTC) Received: from madcap2.tricolour.ca (unknown [10.10.110.28]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0901871662; Sat, 27 Jun 2020 13:23:29 +0000 (UTC) From: Richard Guy Briggs To: containers@lists.linux-foundation.org, linux-api@vger.kernel.org, Linux-Audit Mailing List , linux-fsdevel@vger.kernel.org, LKML , netdev@vger.kernel.org, netfilter-devel@vger.kernel.org Cc: Paul Moore , sgrubb@redhat.com, omosnace@redhat.com, dhowells@redhat.com, simo@redhat.com, eparis@parisplace.org, serge@hallyn.com, ebiederm@xmission.com, nhorman@tuxdriver.com, dwalsh@redhat.com, mpatel@redhat.com, Richard Guy Briggs Subject: [PATCH ghak90 V9 12/13] audit: track container nesting Date: Sat, 27 Jun 2020 09:20:45 -0400 Message-Id: <1d793e2fc60650de4bbc9f4bde3c736c94efe9a1.1593198710.git.rgb@redhat.com> In-Reply-To: References: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Track the parent container of a container to be able to filter and report nesting. Now that we have a way to track and check the parent container of a container, modify the contid field format to be able to report that nesting using a carrat ("^") modifier to indicate nesting. The original field format was "contid=" for task-associated records and "contid=[,[...]]" for network-namespace-associated records. The new field format is "contid=[,^[...]][,[...]]". Signed-off-by: Richard Guy Briggs --- include/linux/audit.h | 1 + kernel/audit.c | 60 ++++++++++++++++++++++++++++++++++++++++++--------- kernel/audit.h | 2 ++ kernel/auditfilter.c | 17 ++++++++++++++- kernel/auditsc.c | 2 +- 5 files changed, 70 insertions(+), 12 deletions(-) diff --git a/include/linux/audit.h b/include/linux/audit.h index 304fbb7c3c5b..025b52ae8422 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -115,6 +115,7 @@ struct audit_contobj { refcount_t refcount; refcount_t sigflag; struct rcu_head rcu; + struct audit_contobj *parent; }; struct audit_task_info { diff --git a/kernel/audit.c b/kernel/audit.c index efa65ec01239..aaf74702e993 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -221,6 +221,7 @@ struct audit_reply { void audit_netns_contid_add(struct net *net, struct audit_contobj *cont); void audit_netns_contid_del(struct net *net, struct audit_contobj *cont); +void audit_log_contid(struct audit_buffer *ab, struct audit_contobj *cont); void __init audit_task_init(void) { @@ -277,6 +278,7 @@ static void _audit_contobj_put_sig(struct audit_contobj *cont) refcount_set(&cont->sigflag, 0); if (!refcount_read(&cont->refcount)) { put_task_struct(cont->owner); + _audit_contobj_put(cont->parent); list_del_rcu(&cont->list); kfree_rcu(cont, rcu); } @@ -574,7 +576,7 @@ void audit_log_netns_contid_list(struct net *net, struct audit_context *context) audit_log_format(ab, "contid="); } else audit_log_format(ab, ","); - audit_log_format(ab, "%llu", cont->obj->id); + audit_log_contid(ab, cont->obj); } audit_log_end(ab); out: @@ -1747,7 +1749,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) kfree(sig_data); break; case AUDIT_SIGNAL_INFO2: { + char *contidstr = NULL; unsigned int contidstrlen = 0; + struct audit_contobj *cont = audit_sig_cid; len = 0; if (audit_sig_sid) { @@ -1757,13 +1761,27 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) return err; } if (audit_sig_cid) { - contidstr = kmalloc(21, GFP_KERNEL); + contidstr = kmalloc(AUDIT_MESSAGE_TEXT_MAX, GFP_KERNEL); if (!contidstr) { if (audit_sig_sid) security_release_secctx(ctx, len); return -ENOMEM; } - contidstrlen = scnprintf(contidstr, 20, "%llu", audit_sig_cid->id); + rcu_read_lock(); + while (cont) { + if (cont->parent) + contidstrlen += scnprintf(contidstr, + AUDIT_MESSAGE_TEXT_MAX - + contidstrlen, + "%llu,^", cont->id); + else + contidstrlen += scnprintf(contidstr, + AUDIT_MESSAGE_TEXT_MAX - + contidstrlen, + "%llu", cont->id); + cont = cont->parent; + } + rcu_read_unlock(); } sig_data2 = kmalloc(sizeof(*sig_data2) + contidstrlen + len, GFP_KERNEL); if (!sig_data2) { @@ -2444,6 +2462,23 @@ void audit_log_session_info(struct audit_buffer *ab) audit_log_format(ab, "auid=%u ses=%u", auid, sessionid); } +void audit_log_contid(struct audit_buffer *ab, struct audit_contobj *cont) +{ + if (!cont) { + audit_log_format(ab, "-1"); + return; + } + rcu_read_lock(); + while (cont) { + if (cont->parent) + audit_log_format(ab, "%llu,^", cont->id); + else + audit_log_format(ab, "%llu", cont->id); + cont = cont->parent; + } + rcu_read_unlock(); +} + /* * audit_log_container_id - report container info * @context: task or local context for record @@ -2460,7 +2495,8 @@ void audit_log_container_id(struct audit_context *context, ab = audit_log_start(context, GFP_KERNEL, AUDIT_CONTAINER_ID); if (!ab) return; - audit_log_format(ab, "contid=%llu", contid); + audit_log_format(ab, "contid="); + audit_log_contid(ab, cont); audit_log_end(ab); } EXPORT_SYMBOL(audit_log_container_id); @@ -2810,6 +2846,7 @@ int audit_set_contid(struct task_struct *task, u64 contid) INIT_LIST_HEAD(&newcont->list); newcont->id = contid; newcont->owner = get_task_struct(current); + newcont->parent = _audit_contobj_get(newcont->owner); refcount_set(&newcont->refcount, 1); list_add_rcu(&newcont->list, &audit_contid_hash[h]); @@ -2828,6 +2865,7 @@ int audit_set_contid(struct task_struct *task, u64 contid) audit_netns_contid_add(net, newcont); } conterror: + rcu_read_unlock(); task_unlock(task); if (!audit_enabled) @@ -2837,12 +2875,13 @@ int audit_set_contid(struct task_struct *task, u64 contid) if (!ab) return rc; - audit_log_format(ab, - "op=set opid=%d contid=%llu old-contid=%llu", - task_tgid_nr(task), contid, oldcont ? oldcont->id : -1); + audit_log_format(ab, "op=set opid=%d contid=%llu old-contid=", + task_tgid_nr(task), contid); + audit_log_contid(ab, oldcont); + audit_log_end(ab); + rcu_read_lock(); _audit_contobj_put(oldcont); rcu_read_unlock(); - audit_log_end(ab); return rc; } @@ -2859,8 +2898,9 @@ void audit_log_container_drop(void) ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_CONTAINER_OP); if (!ab) goto out; - audit_log_format(ab, "op=drop opid=%d contid=%llu old-contid=%llu", - task_tgid_nr(current), cont->id, cont->id); + audit_log_format(ab, "op=drop opid=%d contid=%llu old-contid=", + task_tgid_nr(current), AUDIT_CID_UNSET); + audit_log_contid(ab, cont); audit_log_end(ab); out: rcu_read_unlock(); diff --git a/kernel/audit.h b/kernel/audit.h index 34d8ec4bc6ef..7bea5b51124b 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -229,6 +229,8 @@ static inline int audit_hash_contid(u64 contid) extern int audit_match_class(int class, unsigned syscall); extern int audit_comparator(const u32 left, const u32 op, const u32 right); extern int audit_comparator64(const u64 left, const u32 op, const u64 right); +extern int audit_contid_comparator(const u64 left, const u32 op, + const u64 right); extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right); extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right); extern int parent_len(const char *path); diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index d812698efc1d..981c72a8b863 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -1302,6 +1302,21 @@ int audit_gid_comparator(kgid_t left, u32 op, kgid_t right) } } +int audit_contid_comparator(u64 left, u32 op, u64 right) +{ + struct audit_contobj *cont = NULL; + int h; + int result = 0; + + h = audit_hash_contid(left); + list_for_each_entry_rcu(cont, &audit_contid_hash[h], list) { + result = audit_comparator64(cont->id, op, right); + if (result) + break; + } + return result; +} + /** * parent_len - find the length of the parent portion of a pathname * @path: pathname of which to determine length @@ -1393,7 +1408,7 @@ int audit_filter(int msgtype, unsigned int listtype) f->op, f->val); break; case AUDIT_CONTID: - result = audit_comparator64(audit_get_contid(current), + result = audit_contid_comparator(audit_get_contid(current), f->op, f->val64); break; case AUDIT_MSGTYPE: diff --git a/kernel/auditsc.c b/kernel/auditsc.c index baa5709590b4..9198857ac721 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -641,7 +641,7 @@ static int audit_filter_rules(struct task_struct *tsk, f->op, f->val); break; case AUDIT_CONTID: - result = audit_comparator64(audit_get_contid(tsk), + result = audit_contid_comparator(audit_get_contid(tsk), f->op, f->val64); break; case AUDIT_SUBJ_USER: