From 0d56a4518d5eaf595a24ab2202e171330bb2ed72 Mon Sep 17 00:00:00 2001
From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Thu, 21 Jan 2021 14:19:30 +0100
Subject: [Backport 0d56a4518d5e] stat: handle idmapped mounts

The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
 src/file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/file.c b/src/file.c
index ace35aa8e64b7f416f26cfa194253d27389dfc7f..e9705b3295d31def9c56d86955da9ef359fd9567 100644
--- a/src/file.c
+++ b/src/file.c
@@ -273,7 +273,7 @@ int exfat_getattr(const struct path *path, struct kstat *stat,
 	struct inode *inode = d_backing_inode(path->dentry);
 	struct exfat_inode_info *ei = EXFAT_I(inode);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	exfat_truncate_atime(&stat->atime);
 	stat->result_mask |= STATX_BTIME;
 	stat->btime.tv_sec = ei->i_crtime.tv_sec;
-- 
2.31.1