net/sched: sch_qfq: refactor parsing of netlink parameters

[ Upstream commit 25369891fcef373540f8b4e0b3bccf77a04490d5 ]

Two parameters can be transformed into netlink policies and
validated while parsing the netlink message.

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 3e337087c3b5 ("net/sched: sch_qfq: account for stab overhead in qfq_enqueue")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c
index 02098a02943eb90a67cce829b26a4cf9b79e545c..2f3629c851584bd9956658cbedb70bd6576a3433 100644 (file)
--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -113,6 +113,7 @@
 
 #define QFQ_MTU_SHIFT          16      /* to support TSO/GSO */
 #define QFQ_MIN_LMAX           512     /* see qfq_slot_insert */
+#define QFQ_MAX_LMAX           (1UL << QFQ_MTU_SHIFT)
 
 #define QFQ_MAX_AGG_CLASSES    8 /* max num classes per aggregate allowed */
 
@@ -214,9 +215,14 @@ static struct qfq_class *qfq_find_class(struct Qdisc *sch, u32 classid)
        return container_of(clc, struct qfq_class, common);
 }
 
+static struct netlink_range_validation lmax_range = {
+       .min = QFQ_MIN_LMAX,
+       .max = QFQ_MAX_LMAX,
+};
+
 static const struct nla_policy qfq_policy[TCA_QFQ_MAX + 1] = {
-       [TCA_QFQ_WEIGHT] = { .type = NLA_U32 },
-       [TCA_QFQ_LMAX] = { .type = NLA_U32 },
+       [TCA_QFQ_WEIGHT] = NLA_POLICY_RANGE(NLA_U32, 1, QFQ_MAX_WEIGHT),
+       [TCA_QFQ_LMAX] = NLA_POLICY_FULL_RANGE(NLA_U32, &lmax_range),
 };
 
 /*
@@ -408,17 +414,13 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
        }
 
        err = nla_parse_nested_deprecated(tb, TCA_QFQ_MAX, tca[TCA_OPTIONS],
-                                         qfq_policy, NULL);
+                                         qfq_policy, extack);
        if (err < 0)
                return err;
 
-       if (tb[TCA_QFQ_WEIGHT]) {
+       if (tb[TCA_QFQ_WEIGHT])
                weight = nla_get_u32(tb[TCA_QFQ_WEIGHT]);
-               if (!weight || weight > (1UL << QFQ_MAX_WSHIFT)) {
-                       pr_notice("qfq: invalid weight %u\n", weight);
-                       return -EINVAL;
-               }
-       } else
+       else
                weight = 1;
 
        if (tb[TCA_QFQ_LMAX])
@@ -426,11 +428,6 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
        else
                lmax = psched_mtu(qdisc_dev(sch));
 
-       if (lmax < QFQ_MIN_LMAX || lmax > (1UL << QFQ_MTU_SHIFT)) {
-               pr_notice("qfq: invalid max length %u\n", lmax);
-               return -EINVAL;
-       }
-
        inv_w = ONE_FP / weight;
        weight = ONE_FP / inv_w;