[PATCH] Fix unaligned access in gss_{get,verify}_mic_v2() on sparc64

[James Ettle <james@ettle.org.uk>]

I submitted this patch around a month ago but did it mid-thread and it without the proper subject line. I think it fell off the belt so here it is again. Checked against 4.14.15.


commit a90324ca784dea5a7259a2672c24626f5c03f576
Author: James Ettle <james@ettle.org.uk>
Date:   Thu Dec 7 00:50:28 2017 +0000

    Fix unaligned access on sparc64.

diff --git a/net/sunrpc/auth_gss/gss_krb5_seal.c b/net/sunrpc/auth_gss/gss_krb5_seal.c
index 1d74d653e6c0..94a2b3f082a8 100644
--- a/net/sunrpc/auth_gss/gss_krb5_seal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_seal.c
@@ -177,6 +177,7 @@ gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
 	u64 seq_send;
 	u8 *cksumkey;
 	unsigned int cksum_usage;
+	__be64 seq_send_be64;

 	dprintk("RPC:       %s\n", __func__);

@@ -187,7 +188,9 @@ gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
 	spin_lock(&krb5_seq_lock);
 	seq_send = ctx->seq_send64++;
 	spin_unlock(&krb5_seq_lock);
-	*((__be64 *)(krb5_hdr + 8)) = cpu_to_be64(seq_send);
+
+	seq_send_be64 = cpu_to_be64(seq_send);
+	memcpy(krb5_hdr + 8, (char *) &seq_send_be64, 8);

 	if (ctx->initiate) {
 		cksumkey = ctx->initiator_sign;
diff --git a/net/sunrpc/auth_gss/gss_krb5_unseal.c b/net/sunrpc/auth_gss/gss_krb5_unseal.c
index dcf9515d9aef..8ea6e30d6f3f 100644
--- a/net/sunrpc/auth_gss/gss_krb5_unseal.c
+++ b/net/sunrpc/auth_gss/gss_krb5_unseal.c
@@ -155,10 +155,12 @@ gss_verify_mic_v2(struct krb5_ctx *ctx,
 	u8 flags;
 	int i;
 	unsigned int cksum_usage;
-
+	__be16 be16_ptr;
+	
 	dprintk("RPC:       %s\n", __func__);

-	if (be16_to_cpu(*((__be16 *)ptr)) != KG2_TOK_MIC)
+	memcpy(&be16_ptr, (char *) ptr, 2);
+	if (be16_to_cpu(be16_ptr) != KG2_TOK_MIC)
 		return GSS_S_DEFECTIVE_TOKEN;

 	flags = ptr[2];