From: Lin Ma linma@zju.edu.cn
[ 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@mojatatu.com Signed-off-by: Lin Ma linma@zju.edu.cn Link: https://lore.kernel.org/r/20230725024227.426561-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 1ab20d43c50b0..b99e0fe0229cf 100644 --- a/net/sched/sch_mqprio.c +++ b/net/sched/sch_mqprio.c @@ -174,6 +174,13 @@ 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); @@ -196,6 +203,13 @@ 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);