gss:krb5 miss returning error to caller when import security context

krb5 miss returning error to up layer when import security context,
it may be return ok though it has failed to import security context.

Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c
index 0326446..778e5df 100644
--- a/net/sunrpc/auth_gss/gss_krb5_mech.c
+++ b/net/sunrpc/auth_gss/gss_krb5_mech.c
@@ -237,6 +237,7 @@
 	if (!supported_gss_krb5_enctype(alg)) {
 		printk(KERN_WARNING "gss_kerberos_mech: unsupported "
 			"encryption key algorithm %d\n", alg);
+		p = ERR_PTR(-EINVAL);
 		goto out_err;
 	}
 	p = simple_get_netobj(p, end, &key);
@@ -282,15 +283,19 @@
 	ctx->enctype = ENCTYPE_DES_CBC_RAW;
 
 	ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
-	if (ctx->gk5e == NULL)
+	if (ctx->gk5e == NULL) {
+		p = ERR_PTR(-EINVAL);
 		goto out_err;
+	}
 
 	/* The downcall format was designed before we completely understood
 	 * the uses of the context fields; so it includes some stuff we
 	 * just give some minimal sanity-checking, and some we ignore
 	 * completely (like the next twenty bytes): */
-	if (unlikely(p + 20 > end || p + 20 < p))
+	if (unlikely(p + 20 > end || p + 20 < p)) {
+		p = ERR_PTR(-EFAULT);
 		goto out_err;
+	}
 	p += 20;
 	p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
 	if (IS_ERR(p))
@@ -619,6 +624,7 @@
 	if (ctx->seq_send64 != ctx->seq_send) {
 		dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
 			(long unsigned)ctx->seq_send64, ctx->seq_send);
+		p = ERR_PTR(-EINVAL);
 		goto out_err;
 	}
 	p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));