Btrfs: fix permissions of empty files not affected by umask

When a new file is created with btrfs_create(), the inode will initially be
created with permissions 0666 and later on in btrfs_init_acl() it will be
adapted to mask out the umask bits. The problem is that this change won't make
it into the btrfs_inode unless there's another change to the inode (e.g. writing
content changing the size or touching the file changing the mtime.)

This fix adds a call to btrfs_update_inode() to btrfs_create() to make sure that
the change will not get lost if the in-memory inode is flushed before other
changes are made to the file.

Signed-off-by: Filipe Brandenburger <[email protected]>
Reviewed-by: Liu Bo <[email protected]>
Signed-off-by: Chris Mason <[email protected]>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a1761f01cf11b25c0ebc0dc5dfde83b1033fb5a9..adab791e1ce9d2b2edc03efd47b670e5e67b0980 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4951,6 +4951,12 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
                goto out_unlock;
        }
 
+       err = btrfs_update_inode(trans, root, inode);
+       if (err) {
+               drop_inode = 1;
+               goto out_unlock;
+       }
+
        /*
        * If the active LSM wants to access the inode during
        * d_instantiate it needs these. Smack checks to see