selinux: Consolidate sockcreate_sid logic

Consolidate the basic sockcreate_sid logic into a single helper function
which allows us to do some cleanups in the related code.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 12 insertions, 20 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 190fd0ffb13e..2d94a406574e 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3671,6 +3671,12 @@ static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
 }
 
 /* socket security operations */
+
+static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
+{
+        return tsec->sockcreate_sid ? : tsec->sid;
+}
+
 static int socket_has_perm(struct task_struct *task, struct socket *sock,
                            u32 perms)
 {
@@ -3698,21 +3704,15 @@ static int selinux_socket_create(int family, int type,
 {
         const struct cred *cred = current_cred();
         const struct task_security_struct *tsec = cred->security;
-        u32 sid, newsid;
+        u32 newsid;
         u16 secclass;
-        int err = 0;
 
         if (kern)
-                goto out;
-
-        sid = tsec->sid;
-        newsid = tsec->sockcreate_sid ?: sid;
+                return 0;
 
+        newsid = socket_sockcreate_sid(tsec);
         secclass = socket_type_to_security_class(family, type, protocol);
-        err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
-
-out:
-        return err;
+        return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
 }
 
 static int selinux_socket_post_create(struct socket *sock, int family,
@@ -3720,22 +3720,14 @@ static int selinux_socket_post_create(struct socket *sock, int family,
 {
         const struct cred *cred = current_cred();
         const struct task_security_struct *tsec = cred->security;
-        struct inode_security_struct *isec;
+        struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
         struct sk_security_struct *sksec;
-        u32 sid, newsid;
         int err = 0;
 
-        sid = tsec->sid;
-        newsid = tsec->sockcreate_sid;
-
-        isec = SOCK_INODE(sock)->i_security;
-
         if (kern)
                 isec->sid = SECINITSID_KERNEL;
-        else if (newsid)
-                isec->sid = newsid;
         else
-                isec->sid = sid;
+                isec->sid = socket_sockcreate_sid(tsec);
 
         isec->sclass = socket_type_to_security_class(family, type, protocol);
         isec->initialized = 1;