From e8a64bbaaad1f6548cec5508297bc6d45e8ab69e Mon Sep 17 00:00:00 2001 From: Benedikt Spranger Date: Fri, 8 Apr 2022 11:47:45 +0200 Subject: [PATCH] net/sched: taprio: Check if socket flags are valid A user may set the SO_TXTIME socket option to ensure a packet is send at a given time. The taprio scheduler has to confirm, that it is allowed to send a packet at that given time, by a check against the packet time schedule. The scheduler drop the packet, if the gates are closed at the given send time. The check, if SO_TXTIME is set, may fail since sk_flags are part of an union and the union is used otherwise. This happen, if a socket is not a full socket, like a request socket for example. Add a check to verify, if the union is used for sk_flags. Fixes: 4cfd5779bd6e ("taprio: Add support for txtime-assist mode") Signed-off-by: Benedikt Spranger Reviewed-by: Kurt Kanzenbach Acked-by: Vinicius Costa Gomes Signed-off-by: David S. Miller --- net/sched/sch_taprio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index 377f896bdedc..b9c71a304d39 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -417,7 +417,8 @@ static int taprio_enqueue_one(struct sk_buff *skb, struct Qdisc *sch, { struct taprio_sched *q = qdisc_priv(sch); - if (skb->sk && sock_flag(skb->sk, SOCK_TXTIME)) { + /* sk_flags are only safe to use on full sockets. */ + if (skb->sk && sk_fullsock(skb->sk) && sock_flag(skb->sk, SOCK_TXTIME)) { if (!is_valid_interval(skb, sch)) return qdisc_drop(skb, sch, to_free); } else if (TXTIME_ASSIST_IS_ENABLED(q->flags)) {