Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Aleksander Jan Bajkowski <olek2@wp.pl>,
        Jakub Kicinski <kuba@kernel.org>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.19 093/158] net: lantiq_xrx200: restore buffer if memory allocation failed
Date:   Mon, 29 Aug 2022 12:59:03 +0200
Message-Id: <20220829105812.960262913@linuxfoundation.org>
In-Reply-To: <20220829105808.828227973@linuxfoundation.org>
References: <20220829105808.828227973@linuxfoundation.org>
User-Agent: quilt/0.67
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Aleksander Jan Bajkowski <olek2@wp.pl>

[ 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@wp.pl>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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