From 2bfc47dec5b8b13b16dbab1a266ab9de387ca59b Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 14 Apr 2021 10:40:58 +0200 Subject: [PATCH] cuse: prevent clone [ Upstream commit 8217673d07256b22881127bf50dce874d0e51653 ] 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 Signed-off-by: Sasha Levin --- 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))