From 74e7e1efdad45580cc3839f2a155174cf158f9b5 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Tue, 6 Dec 2022 08:54:24 +0100 Subject: xen/netback: don't call kfree_skb() with interrupts disabled It is not allowed to call kfree_skb() from hardware interrupt context or with interrupts being disabled. So remove kfree_skb() from the spin_lock_irqsave() section and use the already existing "drop" label in xenvif_start_xmit() for dropping the SKB. At the same time replace the dev_kfree_skb() call there with a call of dev_kfree_skb_any(), as xenvif_start_xmit() can be called with disabled interrupts. This is XSA-424 / CVE-2022-42328 / CVE-2022-42329. Fixes: be81992f9086 ("xen/netback: don't queue unlimited number of packages") Reported-by: Yang Yingliang Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Signed-off-by: Juergen Gross --- drivers/net/xen-netback/interface.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/net/xen-netback/interface.c') diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 650fa180220f..f3f2c07423a6 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -254,14 +254,16 @@ xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE) skb_clear_hash(skb); - xenvif_rx_queue_tail(queue, skb); + if (!xenvif_rx_queue_tail(queue, skb)) + goto drop; + xenvif_kick_thread(queue); return NETDEV_TX_OK; drop: vif->dev->stats.tx_dropped++; - dev_kfree_skb(skb); + dev_kfree_skb_any(skb); return NETDEV_TX_OK; } -- cgit