fix mknod() on nfs4 (hopefully)

a) check the right flags in ->create() (LOOKUP_OPEN, not LOOKUP_CREATE)
b) default (!LOOKUP_OPEN) open_flags is O_CREAT|O_EXCL|FMODE_READ, not 0
c) lookup_instantiate_filp() should be done only with LOOKUP_OPEN;
otherwise we need to issue CLOSE, lest we leak stateid on server.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index cc613c354bb84ef7e5c33e346baf2cb653a661f8..1f4625749038ca0074978bead538c21e8c7acd21 100644 (file)
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1567,7 +1567,7 @@ static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode,
        struct nfs_open_context *ctx = NULL;
        struct iattr attr;
        int error;
-       int open_flags = 0;
+       int open_flags = O_CREAT|O_EXCL|FMODE_READ;
 
        dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
@@ -1575,27 +1575,27 @@ static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode,
        attr.ia_mode = mode;
        attr.ia_valid = ATTR_MODE;
 
-       if ((nd->flags & LOOKUP_CREATE) != 0) {
+       if (nd && (nd->flags & LOOKUP_OPEN) != 0)
                open_flags = nd->intent.open.flags;
 
-               ctx = create_nfs_open_context(dentry, open_flags);
-               error = PTR_ERR(ctx);
-               if (IS_ERR(ctx))
-                       goto out_err_drop;
-       }
+       ctx = create_nfs_open_context(dentry, open_flags);
+       error = PTR_ERR(ctx);
+       if (IS_ERR(ctx))
+               goto out_err_drop;
 
        error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, ctx);
        if (error != 0)
                goto out_put_ctx;
-       if (ctx != NULL) {
+       if (nd && (nd->flags & LOOKUP_OPEN) != 0) {
                error = nfs_intent_set_file(nd, ctx);
                if (error < 0)
                        goto out_err;
+       } else {
+               put_nfs_open_context(ctx);
        }
        return 0;
 out_put_ctx:
-       if (ctx != NULL)
-               put_nfs_open_context(ctx);
+       put_nfs_open_context(ctx);
 out_err_drop:
        d_drop(dentry);
 out_err:
@@ -1657,7 +1657,7 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
 {
        struct iattr attr;
        int error;
-       int open_flags = 0;
+       int open_flags = O_CREAT|O_EXCL|FMODE_READ;
 
        dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
@@ -1665,7 +1665,7 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
        attr.ia_mode = mode;
        attr.ia_valid = ATTR_MODE;
 
-       if ((nd->flags & LOOKUP_CREATE) != 0)
+       if (nd && (nd->flags & LOOKUP_OPEN) != 0)
                open_flags = nd->intent.open.flags;
 
        error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, NULL);