From 110c43304db6f06490961529536c362d9ac5732f Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 6 Apr 2012 10:49:10 +0200 Subject: [PATCH] net: fix a race in sock_queue_err_skb() As soon as an skb is queued into socket error queue, another thread can consume it, so we are not allowed to reference skb anymore, or risk use after free. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/skbuff.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index f223cdc75da6..baf8d281152c 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3161,6 +3161,8 @@ static void sock_rmem_free(struct sk_buff *skb) */ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) { + int len = skb->len; + if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= (unsigned)sk->sk_rcvbuf) return -ENOMEM; @@ -3175,7 +3177,7 @@ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) skb_queue_tail(&sk->sk_error_queue, skb); if (!sock_flag(sk, SOCK_DEAD)) - sk->sk_data_ready(sk, skb->len); + sk->sk_data_ready(sk, len); return 0; } EXPORT_SYMBOL(sock_queue_err_skb); -- GitLab