Commit 61adf447 authored by Kuniyuki Iwashima's avatar Kuniyuki Iwashima Committed by David S. Miller
Browse files

net: Fix data-races around netdev_tstamp_prequeue. 



While reading netdev_tstamp_prequeue, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 3b098e2d ("net: Consistent skb timestamping")
Signed-off-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5dcd08cd

net/core/dev.c

+4 −4
Original line number Diff line number Diff line
@@ -4928,7 +4928,7 @@ static int netif_rx_internal(struct sk_buff *skb) 
{

	int ret;



	net_timestamp_check(netdev_tstamp_prequeue, skb);

	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);



	trace_netif_rx(skb);
@@ -5281,7 +5281,7 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 
	int ret = NET_RX_DROP;

	__be16 type;



	net_timestamp_check(!netdev_tstamp_prequeue, skb);

	net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb);



	trace_netif_receive_skb(skb);
@@ -5664,7 +5664,7 @@ static int netif_receive_skb_internal(struct sk_buff *skb) 
{

	int ret;



	net_timestamp_check(netdev_tstamp_prequeue, skb);

	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);



	if (skb_defer_rx_timestamp(skb))

		return NET_RX_SUCCESS;
@@ -5694,7 +5694,7 @@ void netif_receive_skb_list_internal(struct list_head *head) 


	INIT_LIST_HEAD(&sublist);

	list_for_each_entry_safe(skb, next, head, list) {

		net_timestamp_check(netdev_tstamp_prequeue, skb);

		net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);

		skb_list_del_init(skb);

		if (!skb_defer_rx_timestamp(skb))

			list_add_tail(&skb->list, &sublist);