[PATCH v3 2/7] fs/namei.c: Add missing umask strip in vfs_tmpfile

[Yang Xu <xuyang2018.jy@xxxxxxxxxxx>]

If underflying filesystem doesn't enable own CONFIG_FS_POSIX_ACL, then
posix_acl_create can't be called. So we will miss umask strip, ie
use ext4 with noacl or disblae CONFIG_EXT4_FS_POSIX_ACL.

Reported-by: Christian Brauner (Microsoft) <brauner@xxxxxxxxxx>
Signed-off-by: Yang Xu <xuyang2018.jy@xxxxxxxxxxx>
---
 fs/namei.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/namei.c b/fs/namei.c
index 3f1829b3ab5b..bbc7c950bbdc 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3521,6 +3521,8 @@ struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns,
 	child = d_alloc(dentry, &slash_name);
 	if (unlikely(!child))
 		goto out_err;
+	if (!IS_POSIXACL(dir))
+		mode &= ~current_umask();
 	error = dir->i_op->tmpfile(mnt_userns, dir, child, mode);
 	if (error)
 		goto out_err;
-- 
2.27.0