Unverified Commit 2cd45815 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!8666 phonet/pep: fix racy skb_queue_empty() use 

Merge Pull Request from: @ci-robot 
 
PR sync from: Jinjie Ruan <ruanjinjie@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/X2KSETRCQQJSODQQ4YECHH7PG3767P2X/ 
 
https://gitee.com/src-openeuler/kernel/issues/I9Q8LU 
 
Link:https://gitee.com/openeuler/kernel/pulls/8666

 

Reviewed-by: default avatarYue Haibing <yuehaibing@huawei.com>
Signed-off-by: default avatarJialin Zhang <zhangjialin11@huawei.com>
parents 9e1339f3 c9a69d5f

net/phonet/pep.c

+32 −9
Original line number Diff line number Diff line
@@ -916,6 +916,37 @@ static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len) 
	return 0;

}



static unsigned int pep_first_packet_length(struct sock *sk)

{

	struct pep_sock *pn = pep_sk(sk);

	struct sk_buff_head *q;

	struct sk_buff *skb;

	unsigned int len = 0;

	bool found = false;



	if (sock_flag(sk, SOCK_URGINLINE)) {

		q = &pn->ctrlreq_queue;

		spin_lock_bh(&q->lock);

		skb = skb_peek(q);

		if (skb) {

			len = skb->len;

			found = true;

		}

		spin_unlock_bh(&q->lock);

	}



	if (likely(!found)) {

		q = &sk->sk_receive_queue;

		spin_lock_bh(&q->lock);

		skb = skb_peek(q);

		if (skb)

			len = skb->len;

		spin_unlock_bh(&q->lock);

	}



	return len;

}



static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)

{

	struct pep_sock *pn = pep_sk(sk);
@@ -929,15 +960,7 @@ static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg) 
			break;

		}



		lock_sock(sk);

		if (sock_flag(sk, SOCK_URGINLINE) &&

		    !skb_queue_empty(&pn->ctrlreq_queue))

			answ = skb_peek(&pn->ctrlreq_queue)->len;

		else if (!skb_queue_empty(&sk->sk_receive_queue))

			answ = skb_peek(&sk->sk_receive_queue)->len;

		else

			answ = 0;

		release_sock(sk);

		answ = pep_first_packet_length(sk);

		ret = put_user(answ, (int __user *)arg);

		break;