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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 7AC5FC83000 for ; Tue, 28 Apr 2020 22:26:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 55C742072A for ; Tue, 28 Apr 2020 22:26:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=paul-moore-com.20150623.gappssmtp.com header.i=@paul-moore-com.20150623.gappssmtp.com header.b="WRrM+aH1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726424AbgD1W0G (ORCPT ); Tue, 28 Apr 2020 18:26:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726291AbgD1W0G (ORCPT ); Tue, 28 Apr 2020 18:26:06 -0400 Received: from mail-ed1-x544.google.com (mail-ed1-x544.google.com [IPv6:2a00:1450:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B588DC03C1AD for ; Tue, 28 Apr 2020 15:26:05 -0700 (PDT) Received: by mail-ed1-x544.google.com with SMTP id d16so247019edq.7 for ; Tue, 28 Apr 2020 15:26:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=paul-moore-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=o5g+0q4i4NXpQKVni4wkZ3eUg4bn6IsxJhsN8wcx+ak=; b=WRrM+aH1PLLyNr7wFOi3+bCocCitOvbc0DiM8A52L04uR+hAWCFOQELO+cLK3d2ARe 3fnoaqKW2ZykE2NgKVl3lLwgtBpGf/qrj0xtHF5bdG9kyFPB32X9v3qdNMSWuoDH4eAd P/qeU+BVQ30YADghRTV6I4/0jQ2AHy4p6xZ6OG4UmNFAMI5fsxzQASmA7052i7CKJa5G BQj6HQfbLpIFikiQT9JlifLO5YOTILZpQLGoWS7Sjzdz2TahCbEQM2QNeoNZvj/ot+lP hC6YKzmpd/k2trvrC1FyIOeiLG3HskoHMJPIUfCDKaV8xQYX01n1MGcWYRqFYJcIBTRD Dizw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=o5g+0q4i4NXpQKVni4wkZ3eUg4bn6IsxJhsN8wcx+ak=; b=Z/ZlUjjb9gcEPndmcaULc0gdEI+T7aSvKJMd1pLdmAe0EOviDA/wa2b+NDdKsQzL4l x9sCQs/F/XmOxDRM5JPxNDpDQvbWjkT5peRWclzrCZ56MusCAGuVvqbkoOhj/xurVAcz d5XHMiv3ooSAIexIuHJUHKwfGnlToXGw2Tibmwdk197YWbDAjxpGwoTnQDWTxQ70bfV8 wl2+KANWfGPlS8P/DegDvU4gcx5E4CptZaHdNcTXkGuS9QXglc7UlrNSUiqryvdY9JK9 gSjZ0iqQ3NMze9RxTHi/Ivjs+tRj9Uib3oGxcJydZVmBOQhRJGpdUSw6PEJE1plLMxmi rx1g== X-Gm-Message-State: AGi0Pubxn0R9D2gg4cKLG47JVJMT/2uMJ9q2PguzoUW8y5+z53Qc0Qai sB2LmnB6l42F+dE2jiXhWcKoZ+vjO9HCOdlcR5o0nxA= X-Google-Smtp-Source: APiQypJdnPD8twnR2I4zFq1PmUsD3icty6Rtrg9MeAig7VH1vYYfF/k1ac08nAwqqrcf6W3VkkknzI+1g9Lre2mmLyY= X-Received: by 2002:aa7:cd59:: with SMTP id v25mr22787222edw.135.1588112764208; Tue, 28 Apr 2020 15:26:04 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Paul Moore Date: Tue, 28 Apr 2020 18:25:53 -0400 Message-ID: Subject: Re: [PATCH ghak25 v4 3/3] audit: add subj creds to NETFILTER_CFG record to cover async unregister To: Richard Guy Briggs Cc: Linux-Audit Mailing List , LKML , netfilter-devel@vger.kernel.org, sgrubb@redhat.com, omosnace@redhat.com, fw@strlen.de, twoerner@redhat.com, Eric Paris , ebiederm@xmission.com, tgraf@infradead.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 22, 2020 at 5:40 PM Richard Guy Briggs wrote: > Some table unregister actions seem to be initiated by the kernel to > garbage collect unused tables that are not initiated by any userspace > actions. It was found to be necessary to add the subject credentials to > cover this case to reveal the source of these actions. A sample record: > > type=NETFILTER_CFG msg=audit(2020-03-11 21:25:21.491:269) : table=nat family=bridge entries=0 op=unregister pid=153 uid=root auid=unset tty=(none) ses=unset subj=system_u:system_r:kernel_t:s0 comm=kworker/u4:2 exe=(null) [I'm going to comment up here instead of in the code because it is a bit easier for everyone to see what the actual impact might be on the records.] Steve wants subject info in this case, okay, but let's try to trim out some of the fields which simply don't make sense in this record; I'm thinking of fields that are unset/empty in the kernel case and are duplicates of other records in the userspace/syscall case. I think that means we can drop "tty", "ses", "comm", and "exe" ... yes? While "auid" is a potential target for removal based on the dup-or-unset criteria, I think it falls under Steve's request for subject info here, even if it is garbage in this case. > Signed-off-by: Richard Guy Briggs > --- > kernel/auditsc.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index d281c18d1771..d7a45b181be0 100644 > --- a/kernel/auditsc.c > +++ b/kernel/auditsc.c > @@ -2557,12 +2557,30 @@ void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries, > enum audit_nfcfgop op) > { > struct audit_buffer *ab; > + const struct cred *cred; > + struct tty_struct *tty; > + char comm[sizeof(current->comm)]; > > ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_NETFILTER_CFG); > if (!ab) > return; > audit_log_format(ab, "table=%s family=%u entries=%u op=%s", > name, af, nentries, audit_nfcfgs[op].s); > + > + cred = current_cred(); > + tty = audit_get_tty(); > + audit_log_format(ab, " pid=%u uid=%u auid=%u tty=%s ses=%u", > + task_pid_nr(current), > + from_kuid(&init_user_ns, cred->uid), > + from_kuid(&init_user_ns, audit_get_loginuid(current)), > + tty ? tty_name(tty) : "(none)", > + audit_get_sessionid(current)); > + audit_put_tty(tty); > + audit_log_task_context(ab); /* subj= */ > + audit_log_format(ab, " comm="); > + audit_log_untrustedstring(ab, get_task_comm(comm, current)); > + audit_log_d_path_exe(ab, current->mm); /* exe= */ > + > audit_log_end(ab); > } > EXPORT_SYMBOL_GPL(__audit_log_nfcfg); -- paul moore www.paul-moore.com