tun_msg_ctl is used by vhost_net to communicate with tuntap. We will introduce another type in soon. As a preparation this patch adds conditions to check tun_msg_ctl type at necessary places. Signed-off-by: Prashant Bhole <prashantbhole.linux@xxxxxxxxx> --- drivers/net/tap.c | 7 +++++-- drivers/net/tun.c | 6 +++++- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/net/tap.c b/drivers/net/tap.c index 3ae70c7e6860..4df7bf00af66 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -1213,6 +1213,7 @@ static int tap_sendmsg(struct socket *sock, struct msghdr *m, struct tap_queue *q = container_of(sock, struct tap_queue, sock); struct tun_msg_ctl *ctl = m->msg_control; struct xdp_buff *xdp; + void *ptr = NULL; int i; if (ctl && (ctl->type == TUN_MSG_PTR)) { @@ -1223,8 +1224,10 @@ static int tap_sendmsg(struct socket *sock, struct msghdr *m, return 0; } - return tap_get_user(q, ctl ? ctl->ptr : NULL, &m->msg_iter, - m->msg_flags & MSG_DONTWAIT); + if (ctl && ctl->type == TUN_MSG_UBUF) + ptr = ctl->ptr; + + return tap_get_user(q, ptr, &m->msg_iter, m->msg_flags & MSG_DONTWAIT); } static int tap_recvmsg(struct socket *sock, struct msghdr *m, diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 683d371e6e82..1e436d9ec4e1 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -2529,6 +2529,7 @@ static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) struct tun_struct *tun = tun_get(tfile); struct tun_msg_ctl *ctl = m->msg_control; struct xdp_buff *xdp; + void *ptr = NULL; if (!tun) return -EBADFD; @@ -2560,7 +2561,10 @@ static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) goto out; } - ret = tun_get_user(tun, tfile, ctl ? ctl->ptr : NULL, &m->msg_iter, + if (ctl && ctl->type == TUN_MSG_UBUF) + ptr = ctl->ptr; + + ret = tun_get_user(tun, tfile, ptr, &m->msg_iter, m->msg_flags & MSG_DONTWAIT, m->msg_flags & MSG_MORE); out: -- 2.20.1