[PATCH 5.12 074/363] virtiofs: fix userns

From: Greg Kroah-Hartman
Date: Mon May 17 2021 - 10:10:46 EST


From: Miklos Szeredi <mszeredi@xxxxxxxxxx>

[ Upstream commit 0a7419c68a45d2d066b996be5087aa2d07ce80eb ]

get_user_ns() is done twice (once in virtio_fs_get_tree() and once in
fuse_conn_init()), resulting in a reference leak.

Also looks better to use fsc->user_ns (which *should* be the
current_user_ns() at this point).

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/fuse/virtio_fs.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index 1e5affed158e..005209b1cd50 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -1437,8 +1437,7 @@ static int virtio_fs_get_tree(struct fs_context *fsc)
if (!fm)
goto out_err;

- fuse_conn_init(fc, fm, get_user_ns(current_user_ns()),
- &virtio_fs_fiq_ops, fs);
+ fuse_conn_init(fc, fm, fsc->user_ns, &virtio_fs_fiq_ops, fs);
fc->release = fuse_free_conn;
fc->delete_stale = true;
fc->auto_submounts = true;
--
2.30.2