From: Lin Ma <linma@xxxxxxxxxx>
[ Upstream commit 6c58c8816abb7b93b21fa3b1d0c1726402e5e568 ]
The nla_for_each_nested parsing in function mqprio_parse_nlattr() does
not check the length of the nested attribute. This can lead to an
out-of-attribute read and allow a malformed nlattr (e.g., length 0) to
be viewed as 8 byte integer and passed to priv->max_rate/min_rate.
This patch adds the check based on nla_len() when check the nla_type(),
which ensures that the length of these two attribute must equals
sizeof(u64).
Fixes: 4e8b86c06269 ("mqprio: Introduce new hardware offload mode and shaper in mqprio")
Reviewed-by: Victor Nogueira <victor@xxxxxxxxxxxx>
Signed-off-by: Lin Ma <linma@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230725024227.426561-1-linma@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/sched/sch_mqprio.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/net/sched/sch_mqprio.c b/net/sched/sch_mqprio.c
index c9bdb4476a5bc..c0ab1e38e80c6 100644
--- a/net/sched/sch_mqprio.c
+++ b/net/sched/sch_mqprio.c
@@ -176,6 +176,13 @@ static int mqprio_parse_nlattr(struct Qdisc *sch, struct tc_mqprio_qopt *qopt,
"Attribute type expected to be TCA_MQPRIO_MIN_RATE64");
return -EINVAL;
}
+
+ if (nla_len(attr) != sizeof(u64)) {
+ NL_SET_ERR_MSG_ATTR(extack, attr,
+ "Attribute TCA_MQPRIO_MIN_RATE64 expected to have 8 bytes length");
+ return -EINVAL;
+ }
+
if (i >= qopt->num_tc)
break;
priv->min_rate[i] = *(u64 *)nla_data(attr);
@@ -198,6 +205,13 @@ static int mqprio_parse_nlattr(struct Qdisc *sch, struct tc_mqprio_qopt *qopt,
"Attribute type expected to be TCA_MQPRIO_MAX_RATE64");
return -EINVAL;
}
+
+ if (nla_len(attr) != sizeof(u64)) {
+ NL_SET_ERR_MSG_ATTR(extack, attr,
+ "Attribute TCA_MQPRIO_MAX_RATE64 expected to have 8 bytes length");
+ return -EINVAL;
+ }
+
if (i >= qopt->num_tc)
break;
priv->max_rate[i] = *(u64 *)nla_data(attr);
--
2.39.2
