From: Vladyslav Tarasiuk vladyslavt@mellanox.com
[ Upstream commit 9f104c7736904ac72385bbb48669e0c923ca879b ]
When user runs a command like tc qdisc add dev eth1 root mqprio KASAN stack-out-of-bounds warning is emitted. Currently, NLA_ALIGN macro used in mqprio_dump provides too large buffer size as argument for nla_put and memcpy down the call stack. The flow looks like this: 1. nla_put expects exact object size as an argument; 2. Later it provides this size to memcpy; 3. To calculate correct padding for SKB, nla_put applies NLA_ALIGN macro itself.
Therefore, NLA_ALIGN should not be applied to the nla_put parameter. Otherwise it will lead to out-of-bounds memory access in memcpy.
Fixes: 4e8b86c06269 ("mqprio: Introduce new hardware offload mode and shaper in mqprio") Signed-off-by: Vladyslav Tarasiuk vladyslavt@mellanox.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sched/sch_mqprio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/sched/sch_mqprio.c +++ b/net/sched/sch_mqprio.c @@ -435,7 +435,7 @@ static int mqprio_dump(struct Qdisc *sch opt.offset[tc] = dev->tc_to_txq[tc].offset; }
- if (nla_put(skb, TCA_OPTIONS, NLA_ALIGN(sizeof(opt)), &opt)) + if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt)) goto nla_put_failure;
if ((priv->flags & TC_MQPRIO_F_MODE) &&