From d61f2d938135bedf859db6fb4ed07e0ff962eb0b 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 00015d851382..e51b7019e887 100644 --- a/fs/fuse/cuse.c +++ b/fs/fuse/cuse.c @@ -624,6 +624,8 @@ 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))