[PATCH 4/8] netpoll: take rcu_read_lock_bh() in netpoll_rx()
From: Cong Wang <hidden>
Date: 2012-08-06 14:23:55
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
In __netpoll_rx(), it dereferences ->npinfo without rcu_dereference_bh(), this patch fixes it by using the 'npinfo' passed from netpoll_rx() where it is already dereferenced with rcu_dereference_bh(). Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <redacted> --- include/linux/netpoll.h | 4 ++-- net/core/netpoll.c | 3 +-- 2 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h
index 907812e..5d881c3 100644
--- a/include/linux/netpoll.h
+++ b/include/linux/netpoll.h@@ -52,7 +52,7 @@ void netpoll_set_trap(int trap); void __netpoll_cleanup(struct netpoll *np); void __netpoll_free_rcu(struct netpoll *np); void netpoll_cleanup(struct netpoll *np); -int __netpoll_rx(struct sk_buff *skb); +int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo); void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, struct net_device *dev); static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
@@ -77,7 +77,7 @@ static inline bool netpoll_rx(struct sk_buff *skb) spin_lock(&npinfo->rx_lock); /* check rx_flags again with the lock held */ - if (npinfo->rx_flags && __netpoll_rx(skb)) + if (npinfo->rx_flags && __netpoll_rx(skb, npinfo)) ret = true; spin_unlock(&npinfo->rx_lock);
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index dc17f1d..d055bb0 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c@@ -543,13 +543,12 @@ static void arp_reply(struct sk_buff *skb) spin_unlock_irqrestore(&npinfo->rx_lock, flags); } -int __netpoll_rx(struct sk_buff *skb) +int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) { int proto, len, ulen; int hits = 0; const struct iphdr *iph; struct udphdr *uh; - struct netpoll_info *npinfo = skb->dev->npinfo; struct netpoll *np, *tmp; if (list_empty(&npinfo->rx_np))
--
1.7.7.6