SELinux: move common_audit_data to a noinline slow path function

selinux_inode_has_perm is a hot path.  Instead of declaring the
common_audit_data on the stack move it to a noinline function only used in
the rare case we need to send an audit message.

Signed-off-by: Eric Paris <eparis@redhat.com>

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 8417a6afaf30c6a82a499deddab24c68b5a52b77..b3bd8e1d268adf49c6e527fcce1e6effc26cec4d 100644 (file)
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2658,11 +2658,29 @@ static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *na
        return dentry_has_perm(cred, dentry, FILE__READ);
 }
 
-static int selinux_inode_permission(struct inode *inode, int mask)
+static noinline int audit_inode_permission(struct inode *inode,
+                                          u32 perms, u32 audited, u32 denied,
+                                          unsigned flags)
 {
-       const struct cred *cred = current_cred();
        struct common_audit_data ad;
        struct selinux_audit_data sad = {0,};
+       struct inode_security_struct *isec = inode->i_security;
+       int rc;
+
+       COMMON_AUDIT_DATA_INIT(&ad, INODE);
+       ad.selinux_audit_data = &sad;
+       ad.u.inode = inode;
+
+       rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
+                           audited, denied, &ad, flags);
+       if (rc)
+               return rc;
+       return 0;
+}
+
+static int selinux_inode_permission(struct inode *inode, int mask)
+{
+       const struct cred *cred = current_cred();
        u32 perms;
        bool from_access;
        unsigned flags = mask & MAY_NOT_BLOCK;
@@ -2696,15 +2714,7 @@ static int selinux_inode_permission(struct inode *inode, int mask)
        if (likely(!audited))
                return rc;
 
-       COMMON_AUDIT_DATA_INIT(&ad, INODE);
-       ad.selinux_audit_data = &sad;
-       ad.u.inode = inode;
-
-       if (from_access)
-               ad.selinux_audit_data->auditdeny |= FILE__AUDIT_ACCESS;
-
-       rc2 = slow_avc_audit(sid, isec->sid, isec->sclass, perms,
-                            audited, denied, &ad, flags);
+       rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
        if (rc2)
                return rc2;
        return rc;