From c7cc9200e9b4a2ac172e990ef1975cd42975dad6 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Wed, 7 Oct 2020 01:42:46 -0700
Subject: [PATCH] macsec: avoid use-after-free in macsec_handle_frame()
Git-commit: c7cc9200e9b4a2ac172e990ef1975cd42975dad6
Patch-mainline: v5.9
References: git-fixes
De-referencing skb after call to gro_cells_receive() is not allowed.
We need to fetch skb->len earlier.
Fixes: 5491e7c6b1a9 ("macsec: enable GRO and RPS on macsec devices")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/macsec.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -1084,6 +1084,7 @@ static rx_handler_result_t macsec_handle
struct macsec_rx_sa *rx_sa;
struct macsec_rxh_data *rxd;
struct macsec_dev *macsec;
+ unsigned int len;
sci_t sci;
u32 pn;
bool cbit;
@@ -1239,9 +1240,10 @@ deliver:
macsec_rxsc_put(rx_sc);
skb_orphan(skb);
+ len = skb->len;
ret = gro_cells_receive(&macsec->gro_cells, skb);
if (ret == NET_RX_SUCCESS)
- count_rx(dev, skb->len);
+ count_rx(dev, len);
else
macsec->secy.netdev->stats.rx_dropped++;