[PATCH AUTOSEL for 4.14 055/100] net_sched: red: Avoid illegal values

Sasha Levin
2018-01-28T23:07:32Z

From: Nogah Frankel <nogahf@mellanox.com>

[ Upstream commit 8afa10cbe281b10371fee5a87ab266e48d71a7f9 ]

Check the qmin & qmax values doesn't overflow for the given Wlog value.
Check that qmin <= qmax.

Fixes: a783474591f2 ("[PKT_SCHED]: Generic RED layer")
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
include/net/red.h | 11 +++++++++++
net/sched/sch_choke.c | 3 +++
net/sched/sch_gred.c | 3 +++
net/sched/sch_red.c | 2 ++
net/sched/sch_sfq.c | 3 +++
5 files changed, 22 insertions(+)

diff --git a/include/net/red.h b/include/net/red.h
index 5918f78d36a0..9665582c4687 100644
--- a/include/net/red.h
+++ b/include/net/red.h
@@ -168,6 +168,17 @@ static inline void red_set_vars(struct red_vars *v)
v->qcount = -1;
}

+static inline bool red_check_params(u32 qth_min, u32 qth_max, u8 Wlog)
+{
+ if (fls(qth_min) + Wlog > 32)
+ return false;
+ if (fls(qth_max) + Wlog > 32)
+ return false;
+ if (qth_max < qth_min)
+ return false;
+ return true;
+}
+
static inline void red_set_parms(struct red_parms *p,
u32 qth_min, u32 qth_max, u8 Wlog, u8 Plog,
u8 Scell_log, u8 *stab, u32 max_P)
diff --git a/net/sched/sch_choke.c b/net/sched/sch_choke.c
index b30a2c70bd48..531250fceb9e 100644
--- a/net/sched/sch_choke.c
+++ b/net/sched/sch_choke.c
@@ -369,6 +369,9 @@ static int choke_change(struct Qdisc *sch, struct nlattr *opt)

ctl = nla_data(tb[TCA_CHOKE_PARMS]);

+ if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog))
+ return -EINVAL;
+
if (ctl->limit > CHOKE_MAX_QUEUE)
return -EINVAL;

diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c
index 17c7130454bd..bc30f9186ac6 100644
--- a/net/sched/sch_gred.c
+++ b/net/sched/sch_gred.c
@@ -356,6 +356,9 @@ static inline int gred_change_vq(struct Qdisc *sch, int dp,
struct gred_sched *table = qdisc_priv(sch);
struct gred_sched_data *q = table->tab[dp];

+ if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog))
+ return -EINVAL;
+
if (!q) {
table->tab[dp] = q = *prealloc;
*prealloc = NULL;
diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index 93b9d70a9b28..d87c41e82917 100644
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -184,6 +184,8 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt)
max_P = tb[TCA_RED_MAX_P] ? nla_get_u32(tb[TCA_RED_MAX_P]) : 0;

ctl = nla_data(tb[TCA_RED_PARMS]);
+ if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog))
+ return -EINVAL;

if (ctl->limit > 0) {
child = fifo_create_dflt(sch, &bfifo_qdisc_ops, ctl->limit);
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index 74ea863b8240..3fbf20126045 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -637,6 +637,9 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt)
if (ctl->divisor &&
(!is_power_of_2(ctl->divisor) || ctl->divisor > 65536))
return -EINVAL;
+ if (ctl_v1 && !red_check_params(ctl_v1->qth_min, ctl_v1->qth_max,
+ ctl_v1->Wlog))
+ return -EINVAL;
if (ctl_v1 && ctl_v1->qth_min) {
p = kmalloc(sizeof(*p), GFP_KERNEL);
if (!p)
--
2.11.0