[PATCH 2/2] selinux: add attributes to avc tracepoint

[Thiébaud Weksteen]

From: Peter Enderborg <peter.enderborg@xxxxxxxx>

Add further attributes to filter the trace events from AVC.

Signed-off-by: Peter Enderborg <peter.enderborg@xxxxxxxx>
Reviewed-by: Thiébaud Weksteen <tweek@xxxxxxxxxx>
---
 include/trace/events/avc.h | 41 ++++++++++++++++++++++++++++----------
 security/selinux/avc.c     | 22 +++++++++++---------
 2 files changed, 44 insertions(+), 19 deletions(-)

diff --git a/include/trace/events/avc.h b/include/trace/events/avc.h
index 07c058a9bbcd..ac5ef2e1c2c5 100644
--- a/include/trace/events/avc.h
+++ b/include/trace/events/avc.h
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
- * Author: Thiébaud Weksteen <tweek@xxxxxxxxxx>
+ * Authors:	Thiébaud Weksteen <tweek@xxxxxxxxxx>
+ *		Peter Enderborg <Peter.Enderborg@xxxxxxxx>
  */
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM avc
@@ -12,23 +13,43 @@
 
 TRACE_EVENT(selinux_audited,
 
-	TP_PROTO(struct selinux_audit_data *sad),
+	TP_PROTO(struct selinux_audit_data *sad,
+		char *scontext,
+		char *tcontext,
+		const char *tclass
+	),
 
-	TP_ARGS(sad),
+	TP_ARGS(sad, scontext, tcontext, tclass),
 
 	TP_STRUCT__entry(
-		__field(unsigned int, tclass)
-		__field(unsigned int, audited)
+		__field(u32, requested)
+		__field(u32, denied)
+		__field(u32, audited)
+		__field(int, result)
+		__string(scontext, scontext)
+		__string(tcontext, tcontext)
+		__string(tclass, tclass)
+		__field(u32, ssid)
+		__field(u32, tsid)
 	),
 
 	TP_fast_assign(
-		__entry->tclass = sad->tclass;
-		__entry->audited = sad->audited;
+		__entry->requested	= sad->requested;
+		__entry->denied		= sad->denied;
+		__entry->audited	= sad->audited;
+		__entry->result		= sad->result;
+		__entry->ssid		= sad->ssid;
+		__entry->tsid		= sad->tsid;
+		__assign_str(tcontext, tcontext);
+		__assign_str(scontext, scontext);
+		__assign_str(tclass, tclass);
 	),
 
-	TP_printk("tclass=%u audited=%x",
-		__entry->tclass,
-		__entry->audited)
+	TP_printk("requested=0x%x denied=0x%x audited=0x%x result=%d ssid=%u tsid=%u scontext=%s tcontext=%s tclass=%s",
+		__entry->requested, __entry->denied, __entry->audited, __entry->result,
+		__entry->ssid, __entry->tsid, __get_str(scontext), __get_str(tcontext),
+		__get_str(tclass)
+	)
 );
 
 #endif
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index b0a0af778b70..7de5cc5169af 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -705,35 +705,39 @@ static void avc_audit_post_callback(struct audit_buffer *ab, void *a)
 {
 	struct common_audit_data *ad = a;
 	struct selinux_audit_data *sad = ad->selinux_audit_data;
-	char *scontext;
+	char *scontext = NULL;
+	char *tcontext = NULL;
+	const char *tclass = NULL;
 	u32 scontext_len;
+	u32 tcontext_len;
 	int rc;
 
-	trace_selinux_audited(sad);
-
 	rc = security_sid_to_context(sad->state, sad->ssid, &scontext,
 				     &scontext_len);
 	if (rc)
 		audit_log_format(ab, " ssid=%d", sad->ssid);
 	else {
 		audit_log_format(ab, " scontext=%s", scontext);
-		kfree(scontext);
 	}
 
-	rc = security_sid_to_context(sad->state, sad->tsid, &scontext,
-				     &scontext_len);
+	rc = security_sid_to_context(sad->state, sad->tsid, &tcontext,
+				     &tcontext_len);
 	if (rc)
 		audit_log_format(ab, " tsid=%d", sad->tsid);
 	else {
-		audit_log_format(ab, " tcontext=%s", scontext);
-		kfree(scontext);
+		audit_log_format(ab, " tcontext=%s", tcontext);
 	}
 
-	audit_log_format(ab, " tclass=%s", secclass_map[sad->tclass-1].name);
+	tclass = secclass_map[sad->tclass-1].name;
+	audit_log_format(ab, " tclass=%s", tclass);
 
 	if (sad->denied)
 		audit_log_format(ab, " permissive=%u", sad->result ? 0 : 1);
 
+	trace_selinux_audited(sad, scontext, tcontext, tclass);
+	kfree(tcontext);
+	kfree(scontext);
+
 	/* in case of invalid context report also the actual context string */
 	rc = security_sid_to_context_inval(sad->state, sad->ssid, &scontext,
 					   &scontext_len);
-- 
2.28.0.163.g6104cc2f0b6-goog