[PATCH v4 2/8] fs: Add missing umask strip in vfs_tmpfile

Yang Xu
2022-04-19T10:46:44Z

All creation paths except for O_TMPFILE handle umask in the vfs directly
if the filesystem doesn't support or enable POSIX ACLs. If the filesystem
does then umask handling is deferred until posix_acl_create().
Because, O_TMPFILE misses umask handling in the vfs it will not honor
umask settings. Fix this by adding the missing umask handling.

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

diff --git a/fs/namei.c b/fs/namei.c
index 509657fdf4f5..73646e28fae0 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