selinux: fix error codes in cond_read_node()

Originally cond_read_node() returned -1 (-EPERM) on errors which was
incorrect.  Now it either propagates the error codes from lower level
functions next_entry() or cond_read_av_list() or it returns -ENOMEM or
-EINVAL.

next_entry() returns -EINVAL.
cond_read_av_list() returns -EINVAL or -ENOMEM.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by:  Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 12 insertions, 8 deletions

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index aac40c7ff28..a2b3b298e60 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -392,24 +392,25 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp)
         struct cond_expr *expr = NULL, *last = NULL;
 
         rc = next_entry(buf, fp, sizeof(u32));
-        if (rc < 0)
-                return -1;
+        if (rc)
+                return rc;
 
         node->cur_state = le32_to_cpu(buf[0]);
 
         len = 0;
         rc = next_entry(buf, fp, sizeof(u32));
-        if (rc < 0)
-                return -1;
+        if (rc)
+                return rc;
 
         /* expr */
         len = le32_to_cpu(buf[0]);
 
         for (i = 0; i < len; i++) {
                 rc = next_entry(buf, fp, sizeof(u32) * 2);
-                if (rc < 0)
+                if (rc)
                         goto err;
 
+                rc = -ENOMEM;
                 expr = kzalloc(sizeof(struct cond_expr), GFP_KERNEL);
                 if (!expr)
                         goto err;
@@ -418,6 +419,7 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp)
                 expr->bool = le32_to_cpu(buf[1]);
 
                 if (!expr_isvalid(p, expr)) {
+                        rc = -EINVAL;
                         kfree(expr);
                         goto err;
                 }
@@ -429,14 +431,16 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp)
                 last = expr;
         }
 
-        if (cond_read_av_list(p, fp, &node->true_list, NULL) != 0)
+        rc = cond_read_av_list(p, fp, &node->true_list, NULL);
+        if (rc)
                 goto err;
-        if (cond_read_av_list(p, fp, &node->false_list, node->true_list) != 0)
+        rc = cond_read_av_list(p, fp, &node->false_list, node->true_list);
+        if (rc)
                 goto err;
         return 0;
 err:
         cond_node_destroy(node);
-        return -1;
+        return rc;
 }
 
 int cond_read_list(struct policydb *p, void *fp)