From 158810b261d02fc7dd92ca9c392d8f8a211a2401 Mon Sep 17 00:00:00 2001 From: Pedro Tammela Date: Tue, 11 Jul 2023 18:01:00 -0300 Subject: [PATCH] net/sched: sch_qfq: reintroduce lmax bound check for MTU 25369891fcef deletes a check for the case where no 'lmax' is specified which 3037933448f6 previously fixed as 'lmax' could be set to the device's MTU without any bound checking for QFQ_LMAX_MIN and QFQ_LMAX_MAX. Therefore, reintroduce the check. Fixes: 25369891fcef ("net/sched: sch_qfq: refactor parsing of netlink parameters") Acked-by: Jamal Hadi Salim Reviewed-by: Eric Dumazet Signed-off-by: Pedro Tammela Reviewed-by: Simon Horman Signed-off-by: Paolo Abeni --- net/sched/sch_qfq.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c index dfd9a99..63a5b27 100644 --- a/net/sched/sch_qfq.c +++ b/net/sched/sch_qfq.c @@ -423,10 +423,17 @@ static int qfq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, else weight = 1; - if (tb[TCA_QFQ_LMAX]) + if (tb[TCA_QFQ_LMAX]) { lmax = nla_get_u32(tb[TCA_QFQ_LMAX]); - else + } else { + /* MTU size is user controlled */ lmax = psched_mtu(qdisc_dev(sch)); + if (lmax < QFQ_MIN_LMAX || lmax > QFQ_MAX_LMAX) { + NL_SET_ERR_MSG_MOD(extack, + "MTU size out of bounds for qfq"); + return -EINVAL; + } + } inv_w = ONE_FP / weight; weight = ONE_FP / inv_w; -- 2.7.4