kernel: backport two fixes for MediaTek Ethernet driver

Fix PSE port assignment for 3rd GMAC on MT7988 and make sure dma_addr
is always initialized to prevent potentially accessing uninitialized
stack memory in the error path.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

2 files changed, 77 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.15/750-v6.5-20-net-ethernet-mtk_eth_soc-fix-uninitialized-variable.patch b/target/linux/generic/backport-5.15/750-v6.5-20-net-ethernet-mtk_eth_soc-fix-uninitialized-variable.patch
new file mode 100644
index 0000000000..7ea0707d9d
--- /dev/null
+++ b/target/linux/generic/backport-5.15/750-v6.5-20-net-ethernet-mtk_eth_soc-fix-uninitialized-variable.patch
@@ -0,0 +1,44 @@
+From e10a35abb3da12b812cfb6fc6137926a0c81e39a Mon Sep 17 00:00:00 2001
+From: Daniel Golle <daniel@makrotopia.org>
+Date: Sun, 10 Sep 2023 22:40:30 +0100
+Subject: [PATCH] net: ethernet: mtk_eth_soc: fix uninitialized variable
+
+Variable dma_addr in function mtk_poll_rx can be uninitialized on
+some of the error paths. In practise this doesn't matter, even random
+data present in uninitialized stack memory can safely be used in the
+way it happens in the error path.
+
+However, in order to make Smatch happy make sure the variable is
+always initialized.
+
+Signed-off-by: Daniel Golle <daniel@makrotopia.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
++++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+@@ -1941,11 +1941,11 @@ static int mtk_poll_rx(struct napi_struc
+ 	u8 *data, *new_data;
+ 	struct mtk_rx_dma_v2 *rxd, trxd;
+ 	int done = 0, bytes = 0;
++	dma_addr_t dma_addr = DMA_MAPPING_ERROR;
+ 
+ 	while (done < budget) {
+ 		unsigned int pktlen, *rxdcsum;
+ 		struct net_device *netdev;
+-		dma_addr_t dma_addr;
+ 		u32 hash, reason;
+ 		int mac = 0;
+ 
+@@ -2122,7 +2122,8 @@ release_desc:
+ 		else
+ 			rxd->rxd2 = RX_DMA_PREP_PLEN0(ring->buf_size);
+ 
+-		if (MTK_HAS_CAPS(eth->soc->caps, MTK_36BIT_DMA))
++		if (MTK_HAS_CAPS(eth->soc->caps, MTK_36BIT_DMA) &&
++		    likely(dma_addr != DMA_MAPPING_ERROR))
+ 			rxd->rxd2 |= RX_DMA_PREP_ADDR64(dma_addr);
+ 
+ 		ring->calc_idx = idx;
diff --git a/target/linux/generic/backport-5.15/750-v6.5-21-net-ethernet-mtk_eth_soc-fix-pse_port-configuration-.patch b/target/linux/generic/backport-5.15/750-v6.5-21-net-ethernet-mtk_eth_soc-fix-pse_port-configuration-.patch
new file mode 100644
index 0000000000..ac3e3a3e67
--- /dev/null
+++ b/target/linux/generic/backport-5.15/750-v6.5-21-net-ethernet-mtk_eth_soc-fix-pse_port-configuration-.patch
@@ -0,0 +1,33 @@
+From 5a124b1fd3e6cb15a943f0cdfe96aa8f6d3d2f39 Mon Sep 17 00:00:00 2001
+From: Lorenzo Bianconi <lorenzo@kernel.org>
+Date: Sat, 9 Sep 2023 20:41:56 +0200
+Subject: [PATCH] net: ethernet: mtk_eth_soc: fix pse_port configuration for
+ MT7988
+
+MT7988 SoC support 3 NICs. Fix pse_port configuration in
+mtk_flow_set_output_device routine if the traffic is offloaded to eth2.
+Rely on mtk_pse_port definitions.
+
+Fixes: 88efedf517e6 ("net: ethernet: mtk_eth_soc: enable nft hw flowtable_offload for MT7988 SoC")
+Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/mediatek/mtk_ppe_offload.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
++++ b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
+@@ -214,9 +214,11 @@ mtk_flow_set_output_device(struct mtk_et
+ 	dsa_port = mtk_flow_get_dsa_port(&dev);
+ 
+ 	if (dev == eth->netdev[0])
+-		pse_port = 1;
++		pse_port = PSE_GDM1_PORT;
+ 	else if (dev == eth->netdev[1])
+-		pse_port = 2;
++		pse_port = PSE_GDM2_PORT;
++	else if (dev == eth->netdev[2])
++		pse_port = PSE_GDM3_PORT;
+ 	else
+ 		return -EOPNOTSUPP;
+