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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F251C19F2A for ; Thu, 11 Aug 2022 02:24:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233758AbiHKCYB (ORCPT ); Wed, 10 Aug 2022 22:24:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233269AbiHKCX7 (ORCPT ); Wed, 10 Aug 2022 22:23:59 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 0C5AD88DCD for ; Wed, 10 Aug 2022 19:23:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660184637; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=BKmemLUUo0rjZIwwGoGKA+UOMDOAhP06FgZjL5gzzjM=; b=OBFeZM1Plrm2HSToqpA50vxOLINGl9SWMKg05VTyTAXvX1rH8FIgkgun3xAgTgKRGVh3sm GTdIxjqLsuOfeWM9bVHrflI0kZs68FdZ221+CFKgQgGv/eApUTT5oOE5d7/wLQUar+UMD+ mMORj2yFKM4HgErM8B7DMB+1Xbfrd8s= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-624-o7Vy4HsZPIGNxeI4VYO2mA-1; Wed, 10 Aug 2022 22:23:54 -0400 X-MC-Unique: o7Vy4HsZPIGNxeI4VYO2mA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 9451918812C5; Thu, 11 Aug 2022 02:23:53 +0000 (UTC) Received: from madcap2.tricolour.ca (unknown [10.22.48.5]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CEEBD2166B26; Thu, 11 Aug 2022 02:23:51 +0000 (UTC) Date: Wed, 10 Aug 2022 22:23:49 -0400 From: Richard Guy Briggs To: Steve Grubb Cc: Linux-Audit Mailing List , LKML , linux-fsdevel@vger.kernel.org, Paul Moore , Eric Paris , Jan Kara , Amir Goldstein Subject: Re: [PATCH v4 4/4] fanotify,audit: deliver fan_info as a hex-encoded string Message-ID: References: <2d8159cec4392029dabfc39b55ac5fbd0faa9fbd.1659996830.git.rgb@redhat.com> <5623945.DvuYhMxLoT@x2> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5623945.DvuYhMxLoT@x2> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-08-10 15:15, Steve Grubb wrote: > Hell Richard, That's quite an introduction! ;-) > On Tuesday, August 9, 2022 1:22:55 PM EDT Richard Guy Briggs wrote: > > Currently the only type of fanotify info that is defined is an audit > > rule number, but convert it to hex encoding to future-proof the field. > > > > Sample record: > > type=FANOTIFY msg=audit(1659730979.839:284): resp=1 fan_type=0 > > fan_info=3F > > I compiled a new kernel and run old user space on this. The above event is > exactly what I see in my audit logs. Why the fan_info=3F? I really would have > expected 0. What if the actual rule number was 63? I think this will work > better to leave everything 0 with old user space. Well, if it is to be consistently hex encoded, that corresponds to "?" if it is to be interpreted as a string. Since the fan_type is 0, fan_info would be invalid, so a value of 0 would be entirely reasonable, hex encoded to fan_info=00. It could also be hex encoded to the string "(none)". If you wanted "0" for fan_type=FAN_RESPONSE_INFO_AUDIT_RULE, that would be fan_info=30 if it were interpreted as a string, or arguably 3F for an integer of rule (decimal) 63. Ultimately, fan_type should determine how fan_info's hex encoded value should be interpreted. But ultimately, the point of this patch is to hex encode the fan_info field value. > -Steve > > > Suggested-by: Paul Moore > > Signed-off-by: Richard Guy Briggs > > --- > > kernel/auditsc.c | 28 +++++++++++++++++++++------- > > 1 file changed, 21 insertions(+), 7 deletions(-) > > > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > > index f000fec52360..0f747015c577 100644 > > --- a/kernel/auditsc.c > > +++ b/kernel/auditsc.c > > @@ -2908,22 +2908,36 @@ void __audit_fanotify(u32 response, size_t len, > > char *buf) > > > > if (!(len && buf)) { > > audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, > > - "resp=%u fan_type=0 fan_info=?", response); > > + "resp=%u fan_type=0 fan_info=3F", response); /* "?" */ > > return; > > } > > while (c >= sizeof(struct fanotify_response_info_header)) { > > + struct audit_context *ctx = audit_context(); > > + struct audit_buffer *ab; > > + > > friar = (struct fanotify_response_info_audit_rule *)buf; > > switch (friar->hdr.type) { > > case FAN_RESPONSE_INFO_AUDIT_RULE: > > if (friar->hdr.len < sizeof(*friar)) { > > - audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, > > - "resp=%u fan_type=%u fan_info=(incomplete)", > > - response, friar->hdr.type); > > + ab = audit_log_start(ctx, GFP_KERNEL, AUDIT_FANOTIFY); > > + if (ab) { > > + audit_log_format(ab, "resp=%u fan_type=%u fan_info=", > > + response, friar- > >hdr.type); > > +#define INCOMPLETE "(incomplete)" > > + audit_log_n_hex(ab, INCOMPLETE, sizeof(INCOMPLETE)); > > + audit_log_end(ab); > > + } > > return; > > } > > - audit_log(audit_context(), GFP_KERNEL, AUDIT_FANOTIFY, > > - "resp=%u fan_type=%u fan_info=%u", > > - response, friar->hdr.type, friar->audit_rule); > > + ab = audit_log_start(ctx, GFP_KERNEL, AUDIT_FANOTIFY); > > + if (ab) { > > + audit_log_format(ab, "resp=%u fan_type=%u fan_info=", > > + response, friar->hdr.type); > > + audit_log_n_hex(ab, (char *)&friar->audit_rule, > > + sizeof(friar->audit_rule)); > > + audit_log_end(ab); > > + > > + } > > } > > c -= friar->hdr.len; > > ib += friar->hdr.len; > > > > - RGB -- Richard Guy Briggs Sr. S/W Engineer, Kernel Security, Base Operating Systems Remote, Ottawa, Red Hat Canada IRC: rgb, SunRaycer Voice: +1.647.777.2635, Internal: (81) 32635