[PATCH v2 054/118] NFSD: Add a separate decoder to handle state_protect_ops

[Chuck Lever <chuck.lever@xxxxxxxxxx>]

Refactor for clarity and de-duplication of code.

Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
 fs/nfsd/nfs4xdr.c |   66 ++++++++++++++++++-----------------------------------
 1 file changed, 23 insertions(+), 43 deletions(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 48cb409f11c2..a74d86564eb7 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -313,32 +313,6 @@ nfsd4_decode_verifier4(struct nfsd4_compoundargs *argp, nfs4_verifier *verf)
 	return nfs_ok;
 }
 
-static __be32
-nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
-{
-	u32 bmlen;
-	DECODE_HEAD;
-
-	bmval[0] = 0;
-	bmval[1] = 0;
-	bmval[2] = 0;
-
-	READ_BUF(4);
-	bmlen = be32_to_cpup(p++);
-	if (bmlen > 1000)
-		goto xdr_error;
-
-	READ_BUF(bmlen << 2);
-	if (bmlen > 0)
-		bmval[0] = be32_to_cpup(p++);
-	if (bmlen > 1)
-		bmval[1] = be32_to_cpup(p++);
-	if (bmlen > 2)
-		bmval[2] = be32_to_cpup(p++);
-
-	DECODE_TAIL;
-}
-
 static __be32
 nfsd4_decode_nfsace4(struct nfsd4_compoundargs *argp, struct nfs4_ace *ace)
 {
@@ -1441,12 +1415,25 @@ static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp,
 	return nfs_ok;
 }
 
+static __be32 nfsd4_decode_state_protect_ops(struct nfsd4_compoundargs *argp,
+					     u32 *must_enforce, u32 me_len,
+					     u32 *must_allow, u32 ma_len)
+{
+	if (xdr_stream_decode_uint32_array(argp->xdr, must_enforce, me_len) < 0)
+		return nfserr_bad_xdr;
+	if (xdr_stream_decode_uint32_array(argp->xdr, must_allow, ma_len) < 0)
+		return nfserr_bad_xdr;
+
+	return nfs_ok;
+}
+
 static __be32
 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
 			 struct nfsd4_exchange_id *exid)
 {
 	int dummy, tmp;
 	DECODE_HEAD;
+	u32 bm[3];
 
 	READ_BUF(NFS4_VERIFIER_SIZE);
 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
@@ -1465,27 +1452,20 @@ nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
 	case SP4_NONE:
 		break;
 	case SP4_MACH_CRED:
-		/* spo_must_enforce */
-		status = nfsd4_decode_bitmap(argp,
-					exid->spo_must_enforce);
-		if (status)
-			goto out;
-		/* spo_must_allow */
-		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
+		status = nfsd4_decode_state_protect_ops(argp,
+							exid->spo_must_enforce,
+							ARRAY_SIZE(exid->spo_must_enforce),
+							exid->spo_must_allow,
+							ARRAY_SIZE(exid->spo_must_allow));
 		if (status)
-			goto out;
+			return status;
 		break;
 	case SP4_SSV:
 		/* ssp_ops */
-		READ_BUF(4);
-		dummy = be32_to_cpup(p++);
-		READ_BUF(dummy * 4);
-		p += dummy;
-
-		READ_BUF(4);
-		dummy = be32_to_cpup(p++);
-		READ_BUF(dummy * 4);
-		p += dummy;
+		status = nfsd4_decode_state_protect_ops(argp, bm, ARRAY_SIZE(bm),
+							bm, ARRAY_SIZE(bm));
+		if (status)
+			return status;
 
 		/* ssp_hash_algs<> */
 		READ_BUF(4);