Netfilter-Devel Archive on lore.kernel.org
 help / color / Atom feed
From: Richard Guy Briggs <rgb@redhat.com>
To: Linux-Audit Mailing List <linux-audit@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>,
	netfilter-devel@vger.kernel.org
Cc: Paul Moore <paul@paul-moore.com>,
	sgrubb@redhat.com, omosnace@redhat.com, fw@strlen.de,
	twoerner@redhat.com, eparis@parisplace.org, tgraf@infradead.org,
	Richard Guy Briggs <rgb@redhat.com>
Subject: [PATCH ghak25 v6a] audit: add subj creds to NETFILTER_CFG record to cover async unregister
Date: Wed, 20 May 2020 14:47:13 -0400
Message-ID: <6404938413ca29b0e0196dd74bacb9b0c1cb6f42.1589993784.git.rgb@redhat.com> (raw)

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:

The uid, auid, tty, ses and exe fields have not been included since they
are in the SYSCALL record and contain nothing useful in the non-user
context.

Here are two sample orphaned records:

  type=NETFILTER_CFG msg=audit(2020-05-20 12:14:36.505:5) : table=filter family=ipv4 entries=0 op=register pid=1 subj=kernel comm=swapper/0

  type=NETFILTER_CFG msg=audit(2020-05-20 12:15:27.701:301) : table=nat family=bridge entries=0 op=unregister pid=30 subj=system_u:system_r:kernel_t:s0 comm=kworker/u4:1

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
---
Changelog:
v6
- remove uid, auid fields as duplicates or unset
- update sample records in patch description

v5
- rebase on upstreamed ghak28 on audit/next v5.7-rc1
- remove tty, ses and exe fields as duplicates or unset
- drop upstreamed patches 1&2 from set

v4
- rebase on audit/next v5.7-rc1
- fix checkpatch.pl errors/warnings in 1/3 and 2/3

v3
- rebase on v5.6-rc1 audit/next
- change audit_nf_cfg to audit_log_nfcfg
- squash 2,3,4,5 to 1 and update patch descriptions
- add subject credentials to cover garbage collecting kernel threads

v2
- Rebase (audit/next 5.5-rc1) to get audit_context access and ebt_register_table ret code
- Split x_tables and ebtables updates
- Check audit_dummy_context
- Store struct audit_nfcfg params in audit_context, abstract to audit_nf_cfg() call
- Restore back to "table, family, entries" from "family, table, entries"
- Log unregistration of tables
- Add "op=" at the end of the AUDIT_NETFILTER_CFG record
- Defer nsid patch (ghak79) to once nsid patchset upstreamed (ghak32)
- Add ghak refs
- Ditch NETFILTER_CFGSOLO record

 kernel/auditsc.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index cfe3486e5f31..468a23390457 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2557,12 +2557,18 @@ void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
 		       enum audit_nfcfgop op)
 {
 	struct audit_buffer *ab;
+	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);
+
+	audit_log_format(ab, " pid=%u", task_pid_nr(current));
+	audit_log_task_context(ab); /* subj= */
+	audit_log_format(ab, " comm=");
+	audit_log_untrustedstring(ab, get_task_comm(comm, current));
 	audit_log_end(ab);
 }
 EXPORT_SYMBOL_GPL(__audit_log_nfcfg);
-- 
1.8.3.1


             reply index

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-20 18:47 Richard Guy Briggs [this message]
2020-05-20 22:24 ` Paul Moore

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6404938413ca29b0e0196dd74bacb9b0c1cb6f42.1589993784.git.rgb@redhat.com \
    --to=rgb@redhat.com \
    --cc=eparis@parisplace.org \
    --cc=fw@strlen.de \
    --cc=linux-audit@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netfilter-devel@vger.kernel.org \
    --cc=omosnace@redhat.com \
    --cc=paul@paul-moore.com \
    --cc=sgrubb@redhat.com \
    --cc=tgraf@infradead.org \
    --cc=twoerner@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Netfilter-Devel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/netfilter-devel/0 netfilter-devel/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 netfilter-devel netfilter-devel/ https://lore.kernel.org/netfilter-devel \
		netfilter-devel@vger.kernel.org
	public-inbox-index netfilter-devel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.netfilter-devel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git