[PATCH 5.19 093/158] net: lantiq_xrx200: restore buffer if memory allocation failed

From: Greg Kroah-Hartman
Date: Mon Aug 29 2022 - 07:59:15 EST


From: Aleksander Jan Bajkowski <olek2@xxxxx>

[ Upstream commit c9c3b1775f80fa21f5bff874027d2ccb10f5d90c ]

In a situation where memory allocation fails, an invalid buffer address
is stored. When this descriptor is used again, the system panics in the
build_skb() function when accessing memory.

Fixes: 7ea6cd16f159 ("lantiq: net: fix duplicated skb in rx descriptor ring")
Signed-off-by: Aleksander Jan Bajkowski <olek2@xxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/lantiq_xrx200.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c
index 25adce7f0c7c0..57f27cc7724e7 100644
--- a/drivers/net/ethernet/lantiq_xrx200.c
+++ b/drivers/net/ethernet/lantiq_xrx200.c
@@ -193,6 +193,7 @@ static int xrx200_alloc_buf(struct xrx200_chan *ch, void *(*alloc)(unsigned int

ch->rx_buff[ch->dma.desc] = alloc(priv->rx_skb_size);
if (!ch->rx_buff[ch->dma.desc]) {
+ ch->rx_buff[ch->dma.desc] = buf;
ret = -ENOMEM;
goto skip;
}
--
2.35.1