[PATCH v1 38/61] NFSD: Add a separate decoder for ssv_sp_parms

[Chuck Lever <chuck.lever@xxxxxxxxxx>]

Refactor for clarity.

Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
 fs/nfsd/nfs4xdr.c |   86 +++++++++++++++++++++++++++++++++--------------------
 1 file changed, 53 insertions(+), 33 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index ece4e8afe19e..4d666e2f8583 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -222,11 +222,13 @@ static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_ne
 	p = xdr_inline_decode(argp->xdr, len);
 	if (!p)
 		goto xdr_error;
-	o->data = svcxdr_tmpalloc(argp, len);
-	if (!o->data)
-		goto nomem;
-	o->len = len;
-	memcpy(o->data, p, len);
+	if (o) {
+		o->data = svcxdr_tmpalloc(argp, len);
+		if (!o->data)
+			goto nomem;
+		o->len = len;
+		memcpy(o->data, p, len);
+	}
 
 	return nfs_ok;
 xdr_error:
@@ -1482,13 +1484,56 @@ static __be32 nfsd4_decode_state_protect_ops(struct nfsd4_compoundargs *argp,
 	return nfsd4_decode_bitmap4(argp, must_allow, ma_len);
 }
 
+/*
+ * This implementation currently does not support SP4_SSV.
+ * This decoder simply skips over these arguments.
+ */
+static __be32 nfsd4_decode_ssv_sp_parms(struct nfsd4_compoundargs *argp)
+{
+	u32 bm[3], count;
+	__be32 status;
+
+	/* ssp_ops */
+	status = nfsd4_decode_state_protect_ops(argp, bm, ARRAY_SIZE(bm),
+						bm, ARRAY_SIZE(bm));
+	if (status)
+		goto out;
+
+	/* ssp_hash_algs<> */
+	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)
+		goto xdr_error;
+	while (count--) {
+		status = nfsd4_decode_opaque(argp, NULL);
+		if (status)
+			goto out;
+	}
+
+	/* ssp_encr_algs<> */
+	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)
+		goto xdr_error;
+	while (count--) {
+		status = nfsd4_decode_opaque(argp, NULL);
+		if (status)
+			goto out;
+	}
+
+	/* ssp_window and ssp_num_gss_handles are ignored */
+	if (!xdr_inline_decode(argp->xdr, sizeof(__be32) * 2))
+		goto xdr_error;
+
+	status = nfs_ok;
+out:
+	return status;
+xdr_error:
+	return nfserr_bad_xdr;
+}
+
 static __be32
 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
 			 struct nfsd4_exchange_id *exid)
 {
-	int dummy, tmp;
 	DECODE_HEAD;
-	u32 bm[3];
+	int dummy;
 
 	READ_BUF(NFS4_VERIFIER_SIZE);
 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
@@ -1516,34 +1561,9 @@ nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
 			goto out;
 		break;
 	case SP4_SSV:
-		/* ssp_ops */
-		status = nfsd4_decode_state_protect_ops(argp, bm, ARRAY_SIZE(bm),
-							bm, ARRAY_SIZE(bm));
+		status = nfsd4_decode_ssv_sp_parms(argp);
 		if (status)
 			goto out;
-
-		/* ssp_hash_algs<> */
-		READ_BUF(4);
-		tmp = be32_to_cpup(p++);
-		while (tmp--) {
-			READ_BUF(4);
-			dummy = be32_to_cpup(p++);
-			READ_BUF(dummy);
-			p += XDR_QUADLEN(dummy);
-		}
-
-		/* ssp_encr_algs<> */
-		READ_BUF(4);
-		tmp = be32_to_cpup(p++);
-		while (tmp--) {
-			READ_BUF(4);
-			dummy = be32_to_cpup(p++);
-			READ_BUF(dummy);
-			p += XDR_QUADLEN(dummy);
-		}
-
-		/* ignore ssp_window and ssp_num_gss_handles: */
-		READ_BUF(8);
 		break;
 	default:
 		goto xdr_error;