From 0a819ba2306f881b7d0df437d5c0936323e9c8b4 Mon Sep 17 00:00:00 2001 From: Pavel Belous Date: Fri, 14 Feb 2020 18:44:55 +0300 Subject: [PATCH] net: atlantic: fix use after free kasan warn commit a4980919ad6a7be548d499bc5338015e1a9191c6 upstream. skb->len is used to calculate statistics after xmit invocation. Under a stress load it may happen that skb will be xmited, rx interrupt will come and skb will be freed, all before xmit function is even returned. Eventually, skb->len will access unallocated area. Moving stats calculation into tx_clean routine. Fixes: 018423e90bee ("net: ethernet: aquantia: Add ring support code") Reported-by: Christophe Vu-Brugier Signed-off-by: Igor Russkikh Signed-off-by: Pavel Belous Signed-off-by: Dmitry Bogdanov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/aquantia/atlantic/aq_nic.c | 4 ---- drivers/net/ethernet/aquantia/atlantic/aq_ring.c | 7 +++++-- 2 files changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c index 8cc34b0..d1de11b 100644 --- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c +++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c @@ -530,10 +530,6 @@ int aq_nic_xmit(struct aq_nic_s *self, struct sk_buff *skb) if (likely(frags)) { err = self->aq_hw_ops->hw_ring_tx_xmit(self->aq_hw, ring, frags); - if (err >= 0) { - ++ring->stats.tx.packets; - ring->stats.tx.bytes += skb->len; - } } else { err = NETDEV_TX_BUSY; } diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c index b3c7994..b03e5fd 100644 --- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c +++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c @@ -162,9 +162,12 @@ bool aq_ring_tx_clean(struct aq_ring_s *self) } } - if (unlikely(buff->is_eop)) - dev_kfree_skb_any(buff->skb); + if (unlikely(buff->is_eop)) { + ++self->stats.rx.packets; + self->stats.tx.bytes += buff->skb->len; + dev_kfree_skb_any(buff->skb); + } buff->pa = 0U; buff->eop_index = 0xffffU; self->sw_head = aq_ring_next_dx(self, self->sw_head); -- 2.7.4