From: Qiujun Huang hqjagain@gmail.com
commit 71811cac8532b2387b3414f7cd8fe9e497482864 upstream.
Needn't call 'rfcomm_dlc_put' here, because 'rfcomm_dlc_exists' didn't increase dlc->refcnt.
Reported-by: syzbot+4496e82090657320efc6@syzkaller.appspotmail.com Signed-off-by: Qiujun Huang hqjagain@gmail.com Suggested-by: Hillf Danton hdanton@sina.com Signed-off-by: Marcel Holtmann marcel@holtmann.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- net/bluetooth/rfcomm/tty.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c index 5e44d84..cf0ccd0 100644 --- a/net/bluetooth/rfcomm/tty.c +++ b/net/bluetooth/rfcomm/tty.c @@ -413,10 +413,8 @@ static int __rfcomm_create_dev(struct sock *sk, void __user *arg) dlc = rfcomm_dlc_exists(&req.src, &req.dst, req.channel); if (IS_ERR(dlc)) return PTR_ERR(dlc); - else if (dlc) { - rfcomm_dlc_put(dlc); + if (dlc) return -EBUSY; - } dlc = rfcomm_dlc_alloc(GFP_KERNEL); if (!dlc) return -ENOMEM;