From 16bda13d90c8d5da243e2cfa1677e62ecce26860 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 6 Feb 2012 15:14:37 -0500 Subject: [PATCH] net: Make qdisc_skb_cb upper size bound explicit. Just like skb->cb[], so that qdisc_skb_cb can be encapsulated inside of other data structures. This is intended to be used by IPoIB so that it can remember addressing information stored at hard_header_ops->create() time that it can fetch when the packet gets to the transmit routine. Signed-off-by: David S. Miller --- include/net/sch_generic.h | 9 ++++++++- net/sched/sch_choke.c | 3 +-- net/sched/sch_netem.c | 3 +-- net/sched/sch_sfb.c | 3 +-- net/sched/sch_sfq.c | 5 ++--- 5 files changed, 13 insertions(+), 10 deletions(-) diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index f6bb08b73ca4..55ce96b53b09 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -220,9 +220,16 @@ struct tcf_proto { struct qdisc_skb_cb { unsigned int pkt_len; - long data[]; + unsigned char data[24]; }; +static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz) +{ + struct qdisc_skb_cb *qcb; + BUILD_BUG_ON(sizeof(skb->cb) < sizeof(unsigned int) + sz); + BUILD_BUG_ON(sizeof(qcb->data) < sz); +} + static inline int qdisc_qlen(const struct Qdisc *q) { return q->q.qlen; diff --git a/net/sched/sch_choke.c b/net/sched/sch_choke.c index e465064d39a3..7e267d7b9c75 100644 --- a/net/sched/sch_choke.c +++ b/net/sched/sch_choke.c @@ -148,8 +148,7 @@ struct choke_skb_cb { static inline struct choke_skb_cb *choke_skb_cb(const struct sk_buff *skb) { - BUILD_BUG_ON(sizeof(skb->cb) < - sizeof(struct qdisc_skb_cb) + sizeof(struct choke_skb_cb)); + qdisc_cb_private_validate(skb, sizeof(struct choke_skb_cb)); return (struct choke_skb_cb *)qdisc_skb_cb(skb)->data; } diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 2776012132ea..e83d61ca78ca 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -130,8 +130,7 @@ struct netem_skb_cb { static inline struct netem_skb_cb *netem_skb_cb(struct sk_buff *skb) { - BUILD_BUG_ON(sizeof(skb->cb) < - sizeof(struct qdisc_skb_cb) + sizeof(struct netem_skb_cb)); + qdisc_cb_private_validate(skb, sizeof(struct netem_skb_cb)); return (struct netem_skb_cb *)qdisc_skb_cb(skb)->data; } diff --git a/net/sched/sch_sfb.c b/net/sched/sch_sfb.c index 96e42cae4c7a..d7eea99333e9 100644 --- a/net/sched/sch_sfb.c +++ b/net/sched/sch_sfb.c @@ -94,8 +94,7 @@ struct sfb_skb_cb { static inline struct sfb_skb_cb *sfb_skb_cb(const struct sk_buff *skb) { - BUILD_BUG_ON(sizeof(skb->cb) < - sizeof(struct qdisc_skb_cb) + sizeof(struct sfb_skb_cb)); + qdisc_cb_private_validate(skb, sizeof(struct sfb_skb_cb)); return (struct sfb_skb_cb *)qdisc_skb_cb(skb)->data; } diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 67494aef9acf..60d47180f043 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -166,9 +166,8 @@ struct sfq_skb_cb { static inline struct sfq_skb_cb *sfq_skb_cb(const struct sk_buff *skb) { - BUILD_BUG_ON(sizeof(skb->cb) < - sizeof(struct qdisc_skb_cb) + sizeof(struct sfq_skb_cb)); - return (struct sfq_skb_cb *)qdisc_skb_cb(skb)->data; + qdisc_cb_private_validate(skb, sizeof(struct sfq_skb_cb)); + return (struct sfq_skb_cb *)qdisc_skb_cb(skb)->data; } static unsigned int sfq_hash(const struct sfq_sched_data *q, -- 2.20.1