Patch "NFSD: Add a separate decoder to handle state_protect_ops" has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    NFSD: Add a separate decoder to handle state_protect_ops

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nfsd-add-a-separate-decoder-to-handle-state_protect_.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 143051192b5db48edf97d76c219f01f9af45d4ac
Author: Chuck Lever <chuck.lever@xxxxxxxxxx>
Date:   Tue Nov 3 11:13:00 2020 -0500

    NFSD: Add a separate decoder to handle state_protect_ops
    
    [ Upstream commit 2548aa784d760567c2a77cbd8b7c55b211167c37 ]
    
    Refactor for clarity and de-duplication of code.
    
    Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 5dad32ab02ec4..15535b14328e4 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -315,32 +315,6 @@ 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;
-}
-
 /**
  * nfsd4_decode_bitmap4 - Decode an NFSv4 bitmap4
  * @argp: NFSv4 compound argument structure
@@ -1496,6 +1470,24 @@ 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,
+			       struct nfsd4_exchange_id *exid)
+{
+	__be32 status;
+
+	status = nfsd4_decode_bitmap4(argp, exid->spo_must_enforce,
+				      ARRAY_SIZE(exid->spo_must_enforce));
+	if (status)
+		return nfserr_bad_xdr;
+	status = nfsd4_decode_bitmap4(argp, exid->spo_must_allow,
+				      ARRAY_SIZE(exid->spo_must_allow));
+	if (status)
+		return nfserr_bad_xdr;
+
+	return nfs_ok;
+}
+
 static __be32
 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
 			 struct nfsd4_exchange_id *exid)
@@ -1520,27 +1512,15 @@ 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);
 		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, exid);
+		if (status)
+			return status;
 
 		/* ssp_hash_algs<> */
 		READ_BUF(4);