[RFC PATCH 25/35] nfsd: take xattr access bits in to account when checking

[Frank van der Linden <fllinden@xxxxxxxxxx>]

Since the NFSv4.2 extended attributes extension defines 3 new access
bits for xattr operations, take them in to account when validating
what the client is asking for, and when checking permissions.

Signed-off-by: Frank van der Linden <fllinden@xxxxxxxxxx>
---
 fs/nfsd/nfs4proc.c | 10 +++++++++-
 fs/nfsd/vfs.c      | 12 ++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 6fc960677644..6ade983dd9b2 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -557,8 +557,16 @@ nfsd4_access(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	     union nfsd4_op_u *u)
 {
 	struct nfsd4_access *access = &u->access;
+	u32 access_full;
 
-	if (access->ac_req_access & ~NFS3_ACCESS_FULL)
+	access_full = NFS3_ACCESS_FULL;
+#ifdef CONFIG_NFSD_V4_XATTR
+	if (cstate->minorversion >= 2)
+		access_full |= NFS4_ACCESS_XALIST | NFS4_ACCESS_XAREAD |
+			       NFS4_ACCESS_XAWRITE;
+#endif
+
+	if (access->ac_req_access & ~access_full)
 		return nfserr_inval;
 
 	access->ac_resp_access = access->ac_req_access;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 99363e7ce044..d76e3041fa8e 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -611,6 +611,12 @@ static struct accessmap	nfs3_regaccess[] = {
     {	NFS3_ACCESS_MODIFY,	NFSD_MAY_WRITE|NFSD_MAY_TRUNC	},
     {	NFS3_ACCESS_EXTEND,	NFSD_MAY_WRITE			},
 
+#ifdef CONFIG_NFSD_V4_XATTR
+    {	NFS4_ACCESS_XAREAD,	NFSD_MAY_READ			},
+    {	NFS4_ACCESS_XAWRITE,	NFSD_MAY_WRITE			},
+    {	NFS4_ACCESS_XALIST,	NFSD_MAY_READ			},
+#endif
+
     {	0,			0				}
 };
 
@@ -621,6 +627,12 @@ static struct accessmap	nfs3_diraccess[] = {
     {	NFS3_ACCESS_EXTEND,	NFSD_MAY_EXEC|NFSD_MAY_WRITE	},
     {	NFS3_ACCESS_DELETE,	NFSD_MAY_REMOVE			},
 
+#ifdef CONFIG_NFSD_V4_XATTR
+    {	NFS4_ACCESS_XAREAD,	NFSD_MAY_READ			},
+    {	NFS4_ACCESS_XAWRITE,	NFSD_MAY_WRITE			},
+    {	NFS4_ACCESS_XALIST,	NFSD_MAY_READ			},
+#endif
+
     {	0,			0				}
 };
 
-- 
2.17.2