selinux: Delete mls_copy_context

This deletes mls_copy_context() in favor of mls_context_cpy() and
replaces mls_scopy_context() with mls_context_cpy_low().

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

security/selinux/ss/context.h

@@ -55,6 +55,29 @@ static inline int mls_context_cpy(struct context *dst, struct context *src)
 	return rc;
 }
 
+/*
+ * Sets both levels in the MLS range of 'dst' to the low level of 'src'.
+ */
+static inline int mls_context_cpy_low(struct context *dst, struct context *src)
+{
+	int rc;
+
+	if (!selinux_mls_enabled)
+		return 0;
+
+	dst->range.level[0].sens = src->range.level[0].sens;
+	rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
+	if (rc)
+		goto out;
+
+	dst->range.level[1].sens = src->range.level[0].sens;
+	rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[0].cat);
+	if (rc)
+		ebitmap_destroy(&dst->range.level[0].cat);
+out:
+	return rc;
+}
+
 static inline int mls_context_cmp(struct context *c1, struct context *c2)
 {
 	if (!selinux_mls_enabled)

security/selinux/ss/mls.c

@@ -270,7 +270,7 @@ int mls_context_to_sid(char oldc,
 		if (!defcon)
 			goto out;
 
-		rc = mls_copy_context(context, defcon);
+		rc = mls_context_cpy(context, defcon);
 		goto out;
 	}
 
@@ -400,26 +400,6 @@ int mls_from_string(char *str, struct context *context, gfp_t gfp_mask)
 	return rc;
 }
 
-/*
- * Copies the effective MLS range from `src' into `dst'.
- */
-static inline int mls_scopy_context(struct context *dst,
-                                    struct context *src)
-{
-	int l, rc = 0;
-
-	/* Copy the MLS range from the source context */
-	for (l = 0; l < 2; l++) {
-		dst->range.level[l].sens = src->range.level[0].sens;
-		rc = ebitmap_cpy(&dst->range.level[l].cat,
-				 &src->range.level[0].cat);
-		if (rc)
-			break;
-	}
-
-	return rc;
-}
-
 /*
  * Copies the MLS range `range' into `context'.
  */
@@ -552,19 +532,19 @@ int mls_compute_sid(struct context *scontext,
 	case AVTAB_CHANGE:
 		if (tclass == SECCLASS_PROCESS)
 			/* Use the process MLS attributes. */
-			return mls_copy_context(newcontext, scontext);
+			return mls_context_cpy(newcontext, scontext);
 		else
 			/* Use the process effective MLS attributes. */
-			return mls_scopy_context(newcontext, scontext);
+			return mls_context_cpy_low(newcontext, scontext);
 	case AVTAB_MEMBER:
 		/* Only polyinstantiate the MLS attributes if
 		   the type is being polyinstantiated */
 		if (newcontext->type != tcontext->type) {
 			/* Use the process effective MLS attributes. */
-			return mls_scopy_context(newcontext, scontext);
+			return mls_context_cpy_low(newcontext, scontext);
 		} else {
 			/* Use the related object MLS attributes. */
-			return mls_copy_context(newcontext, tcontext);
+			return mls_context_cpy(newcontext, tcontext);
 		}
 	default:
 		return -EINVAL;

security/selinux/ss/mls.h

@@ -24,26 +24,6 @@
 #include "context.h"
 #include "policydb.h"
 
-/*
- * Copies the MLS range from `src' into `dst'.
- */
-static inline int mls_copy_context(struct context *dst,
-				   struct context *src)
-{
-	int l, rc = 0;
-
-	/* Copy the MLS range from the source context */
-	for (l = 0; l < 2; l++) {
-		dst->range.level[l].sens = src->range.level[l].sens;
-		rc = ebitmap_cpy(&dst->range.level[l].cat,
-				 &src->range.level[l].cat);
-		if (rc)
-			break;
-	}
-
-	return rc;
-}
-
 int mls_compute_context_len(struct context *context);
 void mls_sid_to_context(struct context *context, char **scontext);
 int mls_context_isvalid(struct policydb *p, struct context *c);

security/selinux/ss/services.c

@@ -1916,11 +1916,10 @@ int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
 	newcon.user = context1->user;
 	newcon.role = context1->role;
 	newcon.type = context1->type;
-	rc = mls_copy_context(&newcon, context2);
+	rc = mls_context_cpy(&newcon, context2);
 	if (rc)
 		goto out_unlock;
 
-
 	/* Check the validity of the new context. */
 	if (!policydb_context_isvalid(&policydb, &newcon)) {
 		rc = convert_context_handle_invalid_context(&newcon);