NFSD: Replace READ* macros that decode the fattr4 security label attribute

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 9b13386..4e87d03 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -324,6 +324,33 @@ nfsd4_decode_acl(struct nfsd4_compoundargs *argp, struct nfs4_acl **acl)
        return nfs_ok;
 }
 
+static noinline __be32
+nfsd4_decode_security_label(struct nfsd4_compoundargs *argp,
+                           struct xdr_netobj *label)
+{
+       u32 lfs, pi, length;
+       __be32 *p;
+
+       if (xdr_stream_decode_u32(argp->xdr, &lfs) < 0)
+               return nfserr_bad_xdr;
+       if (xdr_stream_decode_u32(argp->xdr, &pi) < 0)
+               return nfserr_bad_xdr;
+
+       if (xdr_stream_decode_u32(argp->xdr, &length) < 0)
+               return nfserr_bad_xdr;
+       if (length > NFS4_MAXLABELLEN)
+               return nfserr_badlabel;
+       p = xdr_inline_decode(argp->xdr, length);
+       if (!p)
+               return nfserr_bad_xdr;
+       label->len = length;
+       label->data = svcxdr_dupstr(argp, p, length);
+       if (!label->data)
+               return nfserr_jukebox;
+
+       return nfs_ok;
+}
+
 static __be32
 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
                   struct iattr *iattr, struct nfs4_acl **acl,
@@ -332,7 +359,6 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
        unsigned int starting_pos;
        u32 attrlist4_count;
        u32 dummy32;
-       char *buf;
 
        DECODE_HEAD;
        iattr->ia_valid = 0;
@@ -440,24 +466,12 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
                        return nfserr_bad_xdr;
                }
        }
-
        label->len = 0;
        if (IS_ENABLED(CONFIG_NFSD_V4_SECURITY_LABEL) &&
            bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
-               READ_BUF(4);
-               dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
-               READ_BUF(4);
-               dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
-               READ_BUF(4);
-               dummy32 = be32_to_cpup(p++);
-               READ_BUF(dummy32);
-               if (dummy32 > NFS4_MAXLABELLEN)
-                       return nfserr_badlabel;
-               READMEM(buf, dummy32);
-               label->len = dummy32;
-               label->data = svcxdr_dupstr(argp, buf, dummy32);
-               if (!label->data)
-                       return nfserr_jukebox;
+               status = nfsd4_decode_security_label(argp, label);
+               if (status)
+                       return status;
        }
        if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
                if (!umask)