lantiq: xrx200: backport upstream network fixes

This series contains bug fixes that may occur under
memory pressure.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>

1 files changed, 33 insertions, 0 deletions

diff --git a/target/linux/lantiq/patches-5.10/0717-v6.0-net-lantiq_xrx200-confirm-skb-is-allocated-before-us.patch b/target/linux/lantiq/patches-5.10/0717-v6.0-net-lantiq_xrx200-confirm-skb-is-allocated-before-us.patch
new file mode 100644
index 0000000000..9eaec58033
--- /dev/null
+++ b/target/linux/lantiq/patches-5.10/0717-v6.0-net-lantiq_xrx200-confirm-skb-is-allocated-before-us.patch
@@ -0,0 +1,33 @@
+From c8b043702dc0894c07721c5b019096cebc8c798f Mon Sep 17 00:00:00 2001
+From: Aleksander Jan Bajkowski <olek2@wp.pl>
+Date: Wed, 24 Aug 2022 23:54:06 +0200
+Subject: [PATCH] net: lantiq_xrx200: confirm skb is allocated before using
+
+xrx200_hw_receive() assumes build_skb() always works and goes straight
+to skb_reserve(). However, build_skb() can fail under memory pressure.
+
+Add a check in case build_skb() failed to allocate and return NULL.
+
+Fixes: e015593573b3 ("net: lantiq_xrx200: convert to build_skb")
+Reported-by: Eric Dumazet <edumazet@google.com>
+Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+---
+ drivers/net/ethernet/lantiq_xrx200.c | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+--- a/drivers/net/ethernet/lantiq_xrx200.c
++++ b/drivers/net/ethernet/lantiq_xrx200.c
+@@ -239,6 +239,12 @@ static int xrx200_hw_receive(struct xrx2
+ 	}
+ 
+ 	skb = build_skb(buf, priv->rx_skb_size);
++	if (!skb) {
++		skb_free_frag(buf);
++		net_dev->stats.rx_dropped++;
++		return -ENOMEM;
++	}
++
+ 	skb_reserve(skb, NET_SKB_PAD);
+ 	skb_put(skb, len);
+