From patchwork Tue Jan 12 15:09:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Guy Briggs X-Patchwork-Id: 362702 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, 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 60579C4332D for ; Tue, 12 Jan 2021 15:14:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 29BAC23132 for ; Tue, 12 Jan 2021 15:14:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404945AbhALPN1 (ORCPT ); Tue, 12 Jan 2021 10:13:27 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:56994 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404820AbhALPN0 (ORCPT ); Tue, 12 Jan 2021 10:13:26 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610464319; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:in-reply-to:in-reply-to:references:references; bh=finGuG2ApMK4JJ38FNio/KBQwRfw0aPFGgdls4QF7m4=; b=X6h8lEoP2pU85zYvTwCQOVx/8hbM5tb6K+JlgUJuhvPpGeiWJBAPdvlm3o4AR0ahXwrqYJ AjQpyChq+3qskwK+nELwHM6fAFq2dd0uxZwO46hZQjpxBKBjV5Ys88OOhuYi96owZoqB1r 8F/EeqQa/VfRDlLNE7VyCTkjpHU8Q/o= 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-3-2AuaJkmLOGuh7Uww0biOvQ-1; Tue, 12 Jan 2021 10:11:57 -0500 X-MC-Unique: 2AuaJkmLOGuh7Uww0biOvQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 77664107ACF8; Tue, 12 Jan 2021 15:11:55 +0000 (UTC) Received: from madcap2.tricolour.ca (unknown [10.10.110.8]) by smtp.corp.redhat.com (Postfix) with ESMTP id CF6765D9CD; Tue, 12 Jan 2021 15:11:51 +0000 (UTC) From: Richard Guy Briggs To: Linux Containers List , Linux API , Linux-Audit Mailing List , Linux FSdevel , LKML , Linux NetDev Upstream Mailing List , Netfilter Devel List Cc: Neil Horman , David Howells , "Eric W. Biederman" , Simo Sorce , Eric Paris , mpatel@redhat.com, Serge Hallyn , Kees Cook , Jens Axboe , Christian Brauner , Richard Guy Briggs Subject: [PATCH ghak90 v11 10/11] audit: track container nesting Date: Tue, 12 Jan 2021 10:09:38 -0500 Message-Id: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 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=[,^[...]][,[...]]". For task event example, an orchestrator in contid 1 spawns tasks in contid 2 and contid 3, then the task in contid 2 spawns a task in contid 4. An event happens in the task in contid 4: type=SYSCALL ... type=CONTAINER_ID msg=audit(:): contid=4,^2,^1 For a network namespace event example, an orchestrator in contid 1 in network namespace A spawns peer tasks 2 and 3 in network namespace B. An event happens in network namespace B: type=NETFILTER_PKT ... type=CONTAINER_ID msg=audit(:): contid=2,^1,3,^1 Signed-off-by: Richard Guy Briggs --- kernel/audit.c | 75 +++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 62 insertions(+), 13 deletions(-) diff --git a/kernel/audit.c b/kernel/audit.c index fcb78a6d8e4a..d2e9d803e5fd 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -231,6 +231,7 @@ struct audit_contobj { refcount_t refcount; refcount_t sigcount; struct rcu_head rcu; + struct audit_contobj *parent; }; struct audit_task_info { @@ -253,6 +254,7 @@ struct audit_contobj_netns { static void audit_netns_contid_add(struct net *net, struct audit_contobj *cont); static void audit_netns_contid_del(struct net *net, struct audit_contobj *cont); +static void audit_log_contid(struct audit_buffer *ab, struct audit_contobj *cont); void __init audit_task_init(void) { @@ -378,6 +380,7 @@ static void _audit_contobj_put_sig(struct audit_contobj *cont) if (refcount_dec_and_test(&cont->sigcount)) { if (!refcount_read(&cont->refcount)) { put_task_struct(cont->owner); + _audit_contobj_put(cont->parent); list_del_rcu(&cont->list); kfree_rcu(cont, rcu); } @@ -722,11 +725,11 @@ int audit_log_netns_contid_list(struct net *net, struct audit_context *context) audit_log_lost("out of memory in audit_log_netns_contid_list"); goto out; } - audit_log_format(ab, "record=1 contid=%llu", - cont->obj->id); + audit_log_format(ab, "record=1 contid="); } else { - audit_log_format(ab, ",%llu", cont->obj->id); + audit_log_format(ab, ","); } + audit_log_contid(ab, cont->obj); } audit_log_end(ab); out: @@ -1906,6 +1909,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) case AUDIT_SIGNAL_INFO2: { char *contidstr = NULL; unsigned int contidstrlen = 0; + struct audit_contobj *cont = audit_sig_cid; len = 0; if (audit_sig_sid) { @@ -1915,13 +1919,27 @@ 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) { @@ -2608,6 +2626,23 @@ void audit_log_session_info(struct audit_buffer *ab) audit_log_format(ab, "auid=%u ses=%u", auid, sessionid); } +static 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 @@ -2627,8 +2662,9 @@ static int _audit_log_container_id(struct audit_context *context, ab = audit_log_start(context, GFP_KERNEL, AUDIT_CONTAINER_ID); if (!ab) return 0; - audit_log_format(ab, "record=%d contid=%llu", - record = ++context->contid_records, contobj->id); + audit_log_format(ab, "record=%d contid=", + record = ++context->contid_records); + audit_log_contid(ab, contobj); audit_log_end(ab); return record; } @@ -2664,7 +2700,18 @@ int audit_log_container_id_ctx(struct audit_context *context) int audit_contid_comparator(struct task_struct *tsk, u32 op, u64 right) { - return audit_comparator64(audit_get_contid(tsk), op, right); + struct audit_contobj *cont = NULL; + int h; + int result = 0; + u64 left = audit_get_contid(tsk); + + 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; } void audit_log_key(struct audit_buffer *ab, char *key) @@ -3019,6 +3066,7 @@ int audit_set_contid(struct task_struct *tsk, u64 contid) INIT_LIST_HEAD(&newcont->list); newcont->id = contid; newcont->owner = get_task_struct(current); + newcont->parent = _audit_contobj_get_bytask(newcont->owner); refcount_set(&newcont->refcount, 1); list_add_rcu(&newcont->list, &audit_contid_hash[h]); @@ -3047,9 +3095,9 @@ int audit_set_contid(struct task_struct *tsk, u64 contid) if (!ab) return rc; - audit_log_format(ab, - "op=set opid=%d contid=%llu old-contid=%llu", - task_tgid_nr(tsk), contid, oldcont ? oldcont->id : -1); + audit_log_format(ab, "op=set opid=%d contid=%llu old-contid=", + task_tgid_nr(tsk), contid); + audit_log_contid(ab, oldcont); spin_lock_irqsave(&_audit_contobj_list_lock, flags); _audit_contobj_put(oldcont); spin_unlock_irqrestore(&_audit_contobj_list_lock, flags); @@ -3088,8 +3136,9 @@ 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=-1 old-contid=%llu", - task_tgid_nr(current), cont->id); + audit_log_format(ab, "op=drop opid=%d contid=-1 old-contid=", + task_tgid_nr(current)); + audit_log_contid(ab, cont); audit_log_end(ab); out: spin_lock_irqsave(&_audit_contobj_list_lock, flags);