From: Miklos Szeredi <mszeredi@redhat.com>
Date: Wed, 14 Apr 2021 10:40:58 +0200
Subject: cuse: prevent clone
Git-commit: 8217673d07256b22881127bf50dce874d0e51653
Patch-mainline: v5.13-rc1
References: bsc#1206120
For cloned connections cuse_channel_release() will be called more than
once, resulting in use after free.
Prevent device cloning for CUSE, which does not make sense at this point,
and highly unlikely to be used in real life.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
fs/fuse/cuse.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index 45082269e698..a37528b51798 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -627,6 +627,8 @@ static int __init cuse_init(void)
cuse_channel_fops.owner = THIS_MODULE;
cuse_channel_fops.open = cuse_channel_open;
cuse_channel_fops.release = cuse_channel_release;
+ /* CUSE is not prepared for FUSE_DEV_IOC_CLONE */
+ cuse_channel_fops.unlocked_ioctl = NULL;
cuse_class = class_create(THIS_MODULE, "cuse");
if (IS_ERR(cuse_class))