apparmor: make policy_unpack able to audit different info messages

Switch unpack auditing to using the generic name field in the audit
struct and make it so we can start adding new info messages about
why an unpack failed.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

security/apparmor/include/audit.h

@@ -127,9 +127,9 @@ struct apparmor_audit_data {
 			} fs;
 		};
 		struct {
-			const char *name;
-			long pos;
+			struct aa_profile *profile;
 			const char *ns;
+			long pos;
 		} iface;
 		int signal;
 		struct {

security/apparmor/policy_unpack.c

@@ -85,9 +85,9 @@ static void audit_cb(struct audit_buffer *ab, void *va)
 		audit_log_format(ab, " ns=");
 		audit_log_untrustedstring(ab, aad(sa)->iface.ns);
 	}
-	if (aad(sa)->iface.name) {
+	if (aad(sa)->name) {
 		audit_log_format(ab, " name=");
-		audit_log_untrustedstring(ab, aad(sa)->iface.name);
+		audit_log_untrustedstring(ab, aad(sa)->name);
 	}
 	if (aad(sa)->iface.pos)
 		audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
@@ -114,9 +114,9 @@ static int audit_iface(struct aa_profile *new, const char *ns_name,
 		aad(&sa)->iface.pos = e->pos - e->start;
 	aad(&sa)->iface.ns = ns_name;
 	if (new)
-		aad(&sa)->iface.name = new->base.hname;
+		aad(&sa)->name = new->base.hname;
 	else
-		aad(&sa)->iface.name = name;
+		aad(&sa)->name = name;
 	aad(&sa)->info = info;
 	aad(&sa)->error = error;
 
@@ -583,6 +583,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 {
 	struct aa_profile *profile = NULL;
 	const char *tmpname, *tmpns = NULL, *name = NULL;
+	const char *info = "failed to unpack profile";
 	size_t ns_len;
 	struct rhashtable_params params = { 0 };
 	char *key = NULL;
@@ -604,8 +605,10 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
 	if (tmpns) {
 		*ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
-		if (!*ns_name)
+		if (!*ns_name) {
+			info = "out of memory";
 			goto fail;
+		}
 		name = tmpname;
 	}
 
@@ -624,12 +627,15 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	if (IS_ERR(profile->xmatch)) {
 		error = PTR_ERR(profile->xmatch);
 		profile->xmatch = NULL;
+		info = "bad xmatch";
 		goto fail;
 	}
 	/* xmatch_len is not optional if xmatch is set */
 	if (profile->xmatch) {
-		if (!unpack_u32(e, &tmp, NULL))
+		if (!unpack_u32(e, &tmp, NULL)) {
+			info = "missing xmatch len";
 			goto fail;
+		}
 		profile->xmatch_len = tmp;
 	}
 
@@ -637,8 +643,11 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	(void) unpack_str(e, &profile->disconnected, "disconnected");
 
 	/* per profile debug flags (complain, audit) */
-	if (!unpack_nameX(e, AA_STRUCT, "flags"))
+	if (!unpack_nameX(e, AA_STRUCT, "flags")) {
+		info = "profile missing flags";
 		goto fail;
+	}
+	info = "failed to unpack profile flags";
 	if (!unpack_u32(e, &tmp, NULL))
 		goto fail;
 	if (tmp & PACKED_FLAG_HAT)
@@ -667,6 +676,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 		/* set a default value if path_flags field is not present */
 		profile->path_flags = PATH_MEDIATE_DELETED;
 
+	info = "failed to unpack profile capabilities";
 	if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
 		goto fail;
 	if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
@@ -676,6 +686,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	if (!unpack_u32(e, &tmpcap.cap[0], NULL))
 		goto fail;
 
+	info = "failed to unpack upper profile capabilities";
 	if (unpack_nameX(e, AA_STRUCT, "caps64")) {
 		/* optional upper half of 64 bit caps */
 		if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
@@ -690,6 +701,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 			goto fail;
 	}
 
+	info = "failed to unpack extended profile capabilities";
 	if (unpack_nameX(e, AA_STRUCT, "capsx")) {
 		/* optional extended caps mediation mask */
 		if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
@@ -700,11 +712,14 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 			goto fail;
 	}
 
-	if (!unpack_rlimits(e, profile))
+	if (!unpack_rlimits(e, profile)) {
+		info = "failed to unpack profile rlimits";
 		goto fail;
+	}
 
 	if (unpack_nameX(e, AA_STRUCT, "policydb")) {
 		/* generic policy dfa - optional and may be NULL */
+		info = "failed to unpack policydb";
 		profile->policy.dfa = unpack_dfa(e);
 		if (IS_ERR(profile->policy.dfa)) {
 			error = PTR_ERR(profile->policy.dfa);
@@ -734,6 +749,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	if (IS_ERR(profile->file.dfa)) {
 		error = PTR_ERR(profile->file.dfa);
 		profile->file.dfa = NULL;
+		info = "failed to unpack profile file rules";
 		goto fail;
 	} else if (profile->file.dfa) {
 		if (!unpack_u32(e, &profile->file.start, "dfa_start"))
@@ -746,10 +762,13 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 	} else
 		profile->file.dfa = aa_get_dfa(nulldfa);
 
-	if (!unpack_trans_table(e, profile))
+	if (!unpack_trans_table(e, profile)) {
+		info = "failed to unpack profile transition table";
 		goto fail;
+	}
 
 	if (unpack_nameX(e, AA_STRUCT, "data")) {
+		info = "out of memory";
 		profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
 		if (!profile->data)
 			goto fail;
@@ -761,8 +780,10 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 		params.hashfn = strhash;
 		params.obj_cmpfn = datacmp;
 
-		if (rhashtable_init(profile->data, &params))
+		if (rhashtable_init(profile->data, &params)) {
+			info = "failed to init key, value hash table";
 			goto fail;
+		}
 
 		while (unpack_strdup(e, &key, NULL)) {
 			data = kzalloc(sizeof(*data), GFP_KERNEL);
@@ -784,12 +805,16 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 					       profile->data->p);
 		}
 
-		if (!unpack_nameX(e, AA_STRUCTEND, NULL))
+		if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
+			info = "failed to unpack end of key, value data table";
 			goto fail;
+		}
 	}
 
-	if (!unpack_nameX(e, AA_STRUCTEND, NULL))
+	if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
+		info = "failed to unpack end of profile";
 		goto fail;
+	}
 
 	return profile;
 
@@ -798,8 +823,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 		name = NULL;
 	else if (!name)
 		name = "unknown";
-	audit_iface(profile, NULL, name, "failed to unpack profile", e,
-		    error);
+	audit_iface(profile, NULL, name, info, e, error);
 	aa_free_profile(profile);
 
 	return ERR_PTR(error);