NFSv4: do exact check about attribute specified

Server should return NFS4ERR_ATTRNOTSUPP if an attribute specified is
not supported in current environment.
Operations CREATE, NVERIFY, OPEN, SETATTR and VERIFY should do this check.

This bug is found when do newpynfs tests. The names of the tests that failed
are following:
  CR12 NVF7a NVF7b NVF7c NVF7d NVF7f NVF7r NVF7s
  OPEN15 VF7a VF7b VF7c VF7d VF7f VF7r VF7s

Add function do_check_fattr() to do exact check:
1, Check attribute specified is supported by the NFSv4 server or not.
2, Check FATTR4_WORD0_ACL & FATTR4_WORD0_FS_LOCATIONS are supported
   in current environment or not.
3, Check attribute specified is writable or not.

step 1 and 3 are done in function nfsd4_decode_fattr() but removed
to this function now.

Signed-off-by: Yu Zhiguo <yuzg@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

fs/nfsd/nfs4proc.c

@@ -51,6 +51,78 @@
 
 #define NFSDDBG_FACILITY		NFSDDBG_PROC
 
+static u32 nfsd_attrmask[] = {
+	NFSD_WRITEABLE_ATTRS_WORD0,
+	NFSD_WRITEABLE_ATTRS_WORD1,
+	NFSD_WRITEABLE_ATTRS_WORD2
+};
+
+static u32 nfsd41_ex_attrmask[] = {
+	NFSD_SUPPATTR_EXCLCREAT_WORD0,
+	NFSD_SUPPATTR_EXCLCREAT_WORD1,
+	NFSD_SUPPATTR_EXCLCREAT_WORD2
+};
+
+static __be32
+check_attr_support(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
+		   u32 *bmval, u32 *writable)
+{
+	struct dentry *dentry = cstate->current_fh.fh_dentry;
+	struct svc_export *exp = cstate->current_fh.fh_export;
+
+	/*
+	 * Check about attributes are supported by the NFSv4 server or not.
+	 * According to spec, unsupported attributes return ERR_ATTRNOTSUPP.
+	 */
+	if ((bmval[0] & ~nfsd_suppattrs0(cstate->minorversion)) ||
+	    (bmval[1] & ~nfsd_suppattrs1(cstate->minorversion)) ||
+	    (bmval[2] & ~nfsd_suppattrs2(cstate->minorversion)))
+		return nfserr_attrnotsupp;
+
+	/*
+	 * Check FATTR4_WORD0_ACL & FATTR4_WORD0_FS_LOCATIONS can be supported
+	 * in current environment or not.
+	 */
+	if (bmval[0] & FATTR4_WORD0_ACL) {
+		if (!IS_POSIXACL(dentry->d_inode))
+			return nfserr_attrnotsupp;
+	}
+	if (bmval[0] & FATTR4_WORD0_FS_LOCATIONS) {
+		if (exp->ex_fslocs.locations == NULL)
+			return nfserr_attrnotsupp;
+	}
+
+	/*
+	 * According to spec, read-only attributes return ERR_INVAL.
+	 */
+	if (writable) {
+		if ((bmval[0] & ~writable[0]) || (bmval[1] & ~writable[1]) ||
+		    (bmval[2] & ~writable[2]))
+			return nfserr_inval;
+	}
+
+	return nfs_ok;
+}
+
+static __be32
+nfsd4_check_open_attributes(struct svc_rqst *rqstp,
+	struct nfsd4_compound_state *cstate, struct nfsd4_open *open)
+{
+	__be32 status = nfs_ok;
+
+	if (open->op_create == NFS4_OPEN_CREATE) {
+		if (open->op_createmode == NFS4_CREATE_UNCHECKED
+		    || open->op_createmode == NFS4_CREATE_GUARDED)
+			status = check_attr_support(rqstp, cstate,
+					open->op_bmval, nfsd_attrmask);
+		else if (open->op_createmode == NFS4_CREATE_EXCLUSIVE4_1)
+			status = check_attr_support(rqstp, cstate,
+					open->op_bmval, nfsd41_ex_attrmask);
+	}
+
+	return status;
+}
+
 static inline void
 fh_dup2(struct svc_fh *dst, struct svc_fh *src)
 {
@@ -225,6 +297,10 @@ nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	if (status)
 		goto out;
 
+	status = nfsd4_check_open_attributes(rqstp, cstate, open);
+	if (status)
+		goto out;
+
 	/* Openowner is now set, so sequence id will get bumped.  Now we need
 	 * these checks before we do any creates: */
 	status = nfserr_grace;
@@ -395,6 +471,11 @@ nfsd4_create(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	if (status)
 		return status;
 
+	status = check_attr_support(rqstp, cstate, create->cr_bmval,
+				    nfsd_attrmask);
+	if (status)
+		return status;
+
 	switch (create->cr_type) {
 	case NF4LNK:
 		/* ugh! we have to null-terminate the linktext, or
@@ -689,6 +770,12 @@ nfsd4_setattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	if (status)
 		return status;
 	status = nfs_ok;
+
+	status = check_attr_support(rqstp, cstate, setattr->sa_bmval,
+				    nfsd_attrmask);
+	if (status)
+		goto out;
+
 	if (setattr->sa_acl != NULL)
 		status = nfsd4_set_nfs4_acl(rqstp, &cstate->current_fh,
 					    setattr->sa_acl);
@@ -763,10 +850,10 @@ _nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	if (status)
 		return status;
 
-	if ((verify->ve_bmval[0] & ~nfsd_suppattrs0(cstate->minorversion))
-	    || (verify->ve_bmval[1] & ~nfsd_suppattrs1(cstate->minorversion))
-	    || (verify->ve_bmval[2] & ~nfsd_suppattrs2(cstate->minorversion)))
-		return nfserr_attrnotsupp;
+	status = check_attr_support(rqstp, cstate, verify->ve_bmval, NULL);
+	if (status)
+		return status;
+
 	if ((verify->ve_bmval[0] & FATTR4_WORD0_RDATTR_ERROR)
 	    || (verify->ve_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1))
 		return nfserr_inval;

fs/nfsd/nfs4xdr.c

@@ -244,20 +244,8 @@ nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
 	DECODE_TAIL;
 }
 
-static u32 nfsd_attrmask[] = {
-	NFSD_WRITEABLE_ATTRS_WORD0,
-	NFSD_WRITEABLE_ATTRS_WORD1,
-	NFSD_WRITEABLE_ATTRS_WORD2
-};
-
-static u32 nfsd41_ex_attrmask[] = {
-	NFSD_SUPPATTR_EXCLCREAT_WORD0,
-	NFSD_SUPPATTR_EXCLCREAT_WORD1,
-	NFSD_SUPPATTR_EXCLCREAT_WORD2
-};
-
 static __be32
-nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval, u32 *writable,
+nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
 		   struct iattr *iattr, struct nfs4_acl **acl)
 {
 	int expected_len, len = 0;
@@ -270,18 +258,6 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval, u32 *writable,
 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
 		return status;
 
-	/*
-	 * According to spec, unsupported attributes return ERR_ATTRNOTSUPP;
-	 * read-only attributes return ERR_INVAL.
-	 */
-	if ((bmval[0] & ~nfsd_suppattrs0(argp->minorversion)) ||
-	    (bmval[1] & ~nfsd_suppattrs1(argp->minorversion)) ||
-	    (bmval[2] & ~nfsd_suppattrs2(argp->minorversion)))
-		return nfserr_attrnotsupp;
-	if ((bmval[0] & ~writable[0]) || (bmval[1] & ~writable[1]) ||
-	    (bmval[2] & ~writable[2]))
-		return nfserr_inval;
-
 	READ_BUF(4);
 	READ32(expected_len);
 
@@ -414,8 +390,11 @@ nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval, u32 *writable,
 			goto xdr_error;
 		}
 	}
-	BUG_ON(bmval[2]);	/* no such writeable attr supported yet */
-	if (len != expected_len)
+	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
+	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
+	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
+		READ_BUF(expected_len - len);
+	else if (len != expected_len)
 		goto xdr_error;
 
 	DECODE_TAIL;
@@ -508,8 +487,8 @@ nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create
 	if ((status = check_filename(create->cr_name, create->cr_namelen, nfserr_inval)))
 		return status;
 
-	status = nfsd4_decode_fattr(argp, create->cr_bmval, nfsd_attrmask,
-				    &create->cr_iattr, &create->cr_acl);
+	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
+				    &create->cr_acl);
 	if (status)
 		goto out;
 
@@ -672,7 +651,7 @@ nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
 		case NFS4_CREATE_UNCHECKED:
 		case NFS4_CREATE_GUARDED:
 			status = nfsd4_decode_fattr(argp, open->op_bmval,
-				nfsd_attrmask, &open->op_iattr, &open->op_acl);
+				&open->op_iattr, &open->op_acl);
 			if (status)
 				goto out;
 			break;
@@ -686,8 +665,7 @@ nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
 			READ_BUF(8);
 			COPYMEM(open->op_verf.data, 8);
 			status = nfsd4_decode_fattr(argp, open->op_bmval,
-				nfsd41_ex_attrmask, &open->op_iattr,
-				&open->op_acl);
+				&open->op_iattr, &open->op_acl);
 			if (status)
 				goto out;
 			break;
@@ -883,8 +861,8 @@ nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *seta
 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
 	if (status)
 		return status;
-	return nfsd4_decode_fattr(argp, setattr->sa_bmval, nfsd_attrmask,
-				  &setattr->sa_iattr, &setattr->sa_acl);
+	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
+				  &setattr->sa_acl);
 }
 
 static __be32