SELinux: add more validity checks on policy load

Add more validity checks at policy load time to reject malformed
policies and prevent subsequent out-of-range indexing when in permissive
mode.  Resolves the NULL pointer dereference reported in
https://bugzilla.redhat.com/show_bug.cgi?id=357541.

Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index 45b93a827c80..50ad85d4b77c 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -362,7 +362,8 @@ static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list *
         data.head = NULL;
         data.tail = NULL;
         for (i = 0; i < len; i++) {
-                rc = avtab_read_item(fp, p->policyvers, &p->te_cond_avtab, cond_insertf, &data);
+                rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf,
+                                     &data);
                 if (rc)
                         return rc;