nfs: add support for the umask attribute

Clients can set the umask attribute when creating files to cause the
server to apply it always except when inheriting permissions from the
parent directory.  That way, the new files will end up with the same
permissions as files created locally.

See https://tools.ietf.org/html/draft-ietf-nfsv4-umask-02 for more details.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 12 insertions, 4 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index c5a508669655..d33242c8d95d 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1224,6 +1224,7 @@ static struct nfs4_opendata *nfs4_opendata_alloc(struct dentry *dentry,
 	atomic_inc(&sp->so_count);
 	p->o_arg.open_flags = flags;
 	p->o_arg.fmode = fmode & (FMODE_READ|FMODE_WRITE);
+	p->o_arg.umask = current_umask();
 	p->o_arg.claim = nfs4_map_atomic_open_claim(server, claim);
 	p->o_arg.share_access = nfs4_map_atomic_open_share(server,
 			fmode, flags);
@@ -3337,7 +3338,7 @@ static void nfs4_close_context(struct nfs_open_context *ctx, int is_sync)
 
 #define FATTR4_WORD1_NFS40_MASK (2*FATTR4_WORD1_MOUNTED_ON_FILEID - 1UL)
 #define FATTR4_WORD2_NFS41_MASK (2*FATTR4_WORD2_SUPPATTR_EXCLCREAT - 1UL)
-#define FATTR4_WORD2_NFS42_MASK (2*FATTR4_WORD2_SECURITY_LABEL - 1UL)
+#define FATTR4_WORD2_NFS42_MASK (2*FATTR4_WORD2_MODE_UMASK - 1UL)
 
 static int _nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle)
 {
@@ -4010,6 +4011,7 @@ static int
 nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 		 int flags)
 {
+	struct nfs_server *server = NFS_SERVER(dir);
 	struct nfs4_label l, *ilabel = NULL;
 	struct nfs_open_context *ctx;
 	struct nfs4_state *state;
@@ -4021,7 +4023,8 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 
 	ilabel = nfs4_label_init_security(dir, dentry, sattr, &l);
 
-	sattr->ia_mode &= ~current_umask();
+	if (!(server->attr_bitmask[2] & FATTR4_WORD2_MODE_UMASK))
+		sattr->ia_mode &= ~current_umask();
 	state = nfs4_do_open(dir, ctx, flags, sattr, ilabel, NULL);
 	if (IS_ERR(state)) {
 		status = PTR_ERR(state);
@@ -4229,6 +4232,7 @@ static struct nfs4_createdata *nfs4_alloc_createdata(struct inode *dir,
 		data->arg.attrs = sattr;
 		data->arg.ftype = ftype;
 		data->arg.bitmask = nfs4_bitmask(server, data->label);
+		data->arg.umask = current_umask();
 		data->res.server = server;
 		data->res.fh = &data->fh;
 		data->res.fattr = &data->fattr;
@@ -4326,13 +4330,15 @@ out:
 static int nfs4_proc_mkdir(struct inode *dir, struct dentry *dentry,
 		struct iattr *sattr)
 {
+	struct nfs_server *server = NFS_SERVER(dir);
 	struct nfs4_exception exception = { };
 	struct nfs4_label l, *label = NULL;
 	int err;
 
 	label = nfs4_label_init_security(dir, dentry, sattr, &l);
 
-	sattr->ia_mode &= ~current_umask();
+	if (!(server->attr_bitmask[2] & FATTR4_WORD2_MODE_UMASK))
+		sattr->ia_mode &= ~current_umask();
 	do {
 		err = _nfs4_proc_mkdir(dir, dentry, sattr, label);
 		trace_nfs4_mkdir(dir, &dentry->d_name, err);
@@ -4435,13 +4441,15 @@ out:
 static int nfs4_proc_mknod(struct inode *dir, struct dentry *dentry,
 		struct iattr *sattr, dev_t rdev)
 {
+	struct nfs_server *server = NFS_SERVER(dir);
 	struct nfs4_exception exception = { };
 	struct nfs4_label l, *label = NULL;
 	int err;
 
 	label = nfs4_label_init_security(dir, dentry, sattr, &l);
 
-	sattr->ia_mode &= ~current_umask();
+	if (!(server->attr_bitmask[2] & FATTR4_WORD2_MODE_UMASK))
+		sattr->ia_mode &= ~current_umask();
 	do {
 		err = _nfs4_proc_mknod(dir, dentry, sattr, label, rdev);
 		trace_nfs4_mknod(dir, &dentry->d_name, err);