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From:   Yang Xu <xuyang2018.jy@fujitsu.com>
To:     <linux-fsdevel@vger.kernel.org>
CC:     <ceph-devel@vger.kernel.org>, <linux-nfs@vger.kernel.org>,
        <linux-xfs@vger.kernel.org>, <viro@zeniv.linux.org.uk>,
        <david@fromorbit.com>, <djwong@kernel.org>, <brauner@kernel.org>,
        <jlayton@kernel.org>, <ntfs3@lists.linux.dev>, <chao@kernel.org>,
        <linux-f2fs-devel@lists.sourceforge.net>,
        Yang Xu <xuyang2018.jy@fujitsu.com>
Subject: [PATCH v4 2/8] fs: Add missing umask strip in vfs_tmpfile
Date:   Tue, 19 Apr 2022 19:47:08 +0800
Message-ID: <1650368834-2420-2-git-send-email-xuyang2018.jy@fujitsu.com>
In-Reply-To: <1650368834-2420-1-git-send-email-xuyang2018.jy@fujitsu.com>
References: <1650368834-2420-1-git-send-email-xuyang2018.jy@fujitsu.com>
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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