SELinux: move genfs read to a separate function

move genfs read functionality out of policydb_read() and into a new
function called genfs_read()
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

security/selinux/ss/policydb.c

@@ -655,6 +655,9 @@ static int range_tr_destroy(void *key, void *datum, void *p)
 
 static void ocontext_destroy(struct ocontext *c, int i)
 {
+	if (!c)
+		return;
+
 	context_destroy(&c->context[0]);
 	context_destroy(&c->context[1]);
 	if (i == OCON_ISID || i == OCON_FS ||
@@ -1773,6 +1776,131 @@ static int range_read(struct policydb *p, void *fp)
 	return rc;
 }
 
+static int genfs_read(struct policydb *p, void *fp)
+{
+	int i, j, rc;
+	u32 nel, nel2, len, len2;
+	__le32 buf[1];
+	struct ocontext *l, *c;
+	struct ocontext *newc = NULL;
+	struct genfs *genfs_p, *genfs;
+	struct genfs *newgenfs = NULL;
+
+	rc = next_entry(buf, fp, sizeof(u32));
+	if (rc)
+		goto out;
+	nel = le32_to_cpu(buf[0]);
+
+	for (i = 0; i < nel; i++) {
+		rc = next_entry(buf, fp, sizeof(u32));
+		if (rc)
+			goto out;
+		len = le32_to_cpu(buf[0]);
+
+		rc = -ENOMEM;
+		newgenfs = kzalloc(sizeof(*newgenfs), GFP_KERNEL);
+		if (!newgenfs)
+			goto out;
+
+		rc = -ENOMEM;
+		newgenfs->fstype = kmalloc(len + 1, GFP_KERNEL);
+		if (!newgenfs->fstype)
+			goto out;
+
+		rc = next_entry(newgenfs->fstype, fp, len);
+		if (rc)
+			goto out;
+
+		newgenfs->fstype[len] = 0;
+
+		for (genfs_p = NULL, genfs = p->genfs; genfs;
+		     genfs_p = genfs, genfs = genfs->next) {
+			rc = -EINVAL;
+			if (strcmp(newgenfs->fstype, genfs->fstype) == 0) {
+				printk(KERN_ERR "SELinux:  dup genfs fstype %s\n",
+				       newgenfs->fstype);
+				goto out;
+			}
+			if (strcmp(newgenfs->fstype, genfs->fstype) < 0)
+				break;
+		}
+		newgenfs->next = genfs;
+		if (genfs_p)
+			genfs_p->next = newgenfs;
+		else
+			p->genfs = newgenfs;
+		genfs = newgenfs;
+		newgenfs = NULL;
+
+		rc = next_entry(buf, fp, sizeof(u32));
+		if (rc)
+			goto out;
+
+		nel2 = le32_to_cpu(buf[0]);
+		for (j = 0; j < nel2; j++) {
+			rc = next_entry(buf, fp, sizeof(u32));
+			if (rc)
+				goto out;
+			len = le32_to_cpu(buf[0]);
+
+			rc = -ENOMEM;
+			newc = kzalloc(sizeof(*newc), GFP_KERNEL);
+			if (!newc)
+				goto out;
+
+			rc = -ENOMEM;
+			newc->u.name = kmalloc(len + 1, GFP_KERNEL);
+			if (!newc->u.name)
+				goto out;
+
+			rc = next_entry(newc->u.name, fp, len);
+			if (rc)
+				goto out;
+			newc->u.name[len] = 0;
+
+			rc = next_entry(buf, fp, sizeof(u32));
+			if (rc)
+				goto out;
+
+			newc->v.sclass = le32_to_cpu(buf[0]);
+			rc = context_read_and_validate(&newc->context[0], p, fp);
+			if (rc)
+				goto out;
+
+			for (l = NULL, c = genfs->head; c;
+			     l = c, c = c->next) {
+				rc = -EINVAL;
+				if (!strcmp(newc->u.name, c->u.name) &&
+				    (!c->v.sclass || !newc->v.sclass ||
+				     newc->v.sclass == c->v.sclass)) {
+					printk(KERN_ERR "SELinux:  dup genfs entry (%s,%s)\n",
+					       genfs->fstype, c->u.name);
+					goto out;
+				}
+				len = strlen(newc->u.name);
+				len2 = strlen(c->u.name);
+				if (len > len2)
+					break;
+			}
+
+			newc->next = c;
+			if (l)
+				l->next = newc;
+			else
+				genfs->head = newc;
+			newc = NULL;
+		}
+	}
+	rc = 0;
+out:
+	if (newgenfs)
+		kfree(newgenfs->fstype);
+	kfree(newgenfs);
+	ocontext_destroy(newc, OCON_FSUSE);
+
+	return rc;
+}
+
 /*
  * Read the configuration data from a policy database binary
  * representation file into a policy database structure.
@@ -1781,12 +1909,12 @@ int policydb_read(struct policydb *p, void *fp)
 {
 	struct role_allow *ra, *lra;
 	struct role_trans *tr, *ltr;
-	struct ocontext *l, *c, *newc;
-	struct genfs *genfs_p, *genfs, *newgenfs;
+	struct ocontext *l, *c;
 	int i, j, rc;
 	__le32 buf[4];
 	u32 nodebuf[8];
-	u32 len, len2, nprim, nel, nel2;
+	u32 len, nprim, nel;
+
 	char *policydb_str;
 	struct policydb_compat_info *info;
 
@@ -2099,107 +2227,9 @@ int policydb_read(struct policydb *p, void *fp)
 		}
 	}
 
-	rc = next_entry(buf, fp, sizeof(u32));
-	if (rc < 0)
+	rc = genfs_read(p, fp);
+	if (rc)
 		goto bad;
-	nel = le32_to_cpu(buf[0]);
-	genfs_p = NULL;
-	rc = -EINVAL;
-	for (i = 0; i < nel; i++) {
-		rc = next_entry(buf, fp, sizeof(u32));
-		if (rc < 0)
-			goto bad;
-		len = le32_to_cpu(buf[0]);
-		newgenfs = kzalloc(sizeof(*newgenfs), GFP_KERNEL);
-		if (!newgenfs) {
-			rc = -ENOMEM;
-			goto bad;
-		}
-
-		newgenfs->fstype = kmalloc(len + 1, GFP_KERNEL);
-		if (!newgenfs->fstype) {
-			rc = -ENOMEM;
-			kfree(newgenfs);
-			goto bad;
-		}
-		rc = next_entry(newgenfs->fstype, fp, len);
-		if (rc < 0) {
-			kfree(newgenfs->fstype);
-			kfree(newgenfs);
-			goto bad;
-		}
-		newgenfs->fstype[len] = 0;
-		for (genfs_p = NULL, genfs = p->genfs; genfs;
-		     genfs_p = genfs, genfs = genfs->next) {
-			if (strcmp(newgenfs->fstype, genfs->fstype) == 0) {
-				printk(KERN_ERR "SELinux:  dup genfs "
-				       "fstype %s\n", newgenfs->fstype);
-				kfree(newgenfs->fstype);
-				kfree(newgenfs);
-				goto bad;
-			}
-			if (strcmp(newgenfs->fstype, genfs->fstype) < 0)
-				break;
-		}
-		newgenfs->next = genfs;
-		if (genfs_p)
-			genfs_p->next = newgenfs;
-		else
-			p->genfs = newgenfs;
-		rc = next_entry(buf, fp, sizeof(u32));
-		if (rc < 0)
-			goto bad;
-		nel2 = le32_to_cpu(buf[0]);
-		for (j = 0; j < nel2; j++) {
-			rc = next_entry(buf, fp, sizeof(u32));
-			if (rc < 0)
-				goto bad;
-			len = le32_to_cpu(buf[0]);
-
-			newc = kzalloc(sizeof(*newc), GFP_KERNEL);
-			if (!newc) {
-				rc = -ENOMEM;
-				goto bad;
-			}
-
-			newc->u.name = kmalloc(len + 1, GFP_KERNEL);
-			if (!newc->u.name) {
-				rc = -ENOMEM;
-				goto bad_newc;
-			}
-			rc = next_entry(newc->u.name, fp, len);
-			if (rc < 0)
-				goto bad_newc;
-			newc->u.name[len] = 0;
-			rc = next_entry(buf, fp, sizeof(u32));
-			if (rc < 0)
-				goto bad_newc;
-			newc->v.sclass = le32_to_cpu(buf[0]);
-			if (context_read_and_validate(&newc->context[0], p, fp))
-				goto bad_newc;
-			for (l = NULL, c = newgenfs->head; c;
-			     l = c, c = c->next) {
-				if (!strcmp(newc->u.name, c->u.name) &&
-				    (!c->v.sclass || !newc->v.sclass ||
-				     newc->v.sclass == c->v.sclass)) {
-					printk(KERN_ERR "SELinux:  dup genfs "
-					       "entry (%s,%s)\n",
-					       newgenfs->fstype, c->u.name);
-					goto bad_newc;
-				}
-				len = strlen(newc->u.name);
-				len2 = strlen(c->u.name);
-				if (len > len2)
-					break;
-			}
-
-			newc->next = c;
-			if (l)
-				l->next = newc;
-			else
-				newgenfs->head = newc;
-		}
-	}
 
 	rc = range_read(p, fp);
 	if (rc)
@@ -2227,8 +2257,6 @@ int policydb_read(struct policydb *p, void *fp)
 	rc = 0;
 out:
 	return rc;
-bad_newc:
-	ocontext_destroy(newc, OCON_FSUSE);
 bad:
 	if (!rc)
 		rc = -EINVAL;