mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 02:30:34 +02:00 
			
		
		
		
	tun: free skb in early errors
tun_recvmsg() supports accepting skb by msg_control after
commit ac77cfd425 ("tun: support receiving skb through msg_control"),
the skb if presented should be freed no matter how far it can go
along, otherwise it would be leaked.
This patch fixes several missed cases.
Signed-off-by: Wei Xu <wexu@redhat.com>
Reported-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
			
			
This commit is contained in:
		
							parent
							
								
									6e474083f3
								
							
						
					
					
						commit
						c33ee15b38
					
				
					 1 changed files with 18 additions and 6 deletions
				
			
		| 
						 | 
				
			
			@ -1952,8 +1952,11 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
 | 
			
		|||
 | 
			
		||||
	tun_debug(KERN_INFO, tun, "tun_do_read\n");
 | 
			
		||||
 | 
			
		||||
	if (!iov_iter_count(to))
 | 
			
		||||
	if (!iov_iter_count(to)) {
 | 
			
		||||
		if (skb)
 | 
			
		||||
			kfree_skb(skb);
 | 
			
		||||
		return 0;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	if (!skb) {
 | 
			
		||||
		/* Read frames from ring */
 | 
			
		||||
| 
						 | 
				
			
			@ -2069,22 +2072,24 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len,
 | 
			
		|||
{
 | 
			
		||||
	struct tun_file *tfile = container_of(sock, struct tun_file, socket);
 | 
			
		||||
	struct tun_struct *tun = tun_get(tfile);
 | 
			
		||||
	struct sk_buff *skb = m->msg_control;
 | 
			
		||||
	int ret;
 | 
			
		||||
 | 
			
		||||
	if (!tun)
 | 
			
		||||
		return -EBADFD;
 | 
			
		||||
	if (!tun) {
 | 
			
		||||
		ret = -EBADFD;
 | 
			
		||||
		goto out_free_skb;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	if (flags & ~(MSG_DONTWAIT|MSG_TRUNC|MSG_ERRQUEUE)) {
 | 
			
		||||
		ret = -EINVAL;
 | 
			
		||||
		goto out;
 | 
			
		||||
		goto out_put_tun;
 | 
			
		||||
	}
 | 
			
		||||
	if (flags & MSG_ERRQUEUE) {
 | 
			
		||||
		ret = sock_recv_errqueue(sock->sk, m, total_len,
 | 
			
		||||
					 SOL_PACKET, TUN_TX_TIMESTAMP);
 | 
			
		||||
		goto out;
 | 
			
		||||
	}
 | 
			
		||||
	ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT,
 | 
			
		||||
			  m->msg_control);
 | 
			
		||||
	ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT, skb);
 | 
			
		||||
	if (ret > (ssize_t)total_len) {
 | 
			
		||||
		m->msg_flags |= MSG_TRUNC;
 | 
			
		||||
		ret = flags & MSG_TRUNC ? ret : total_len;
 | 
			
		||||
| 
						 | 
				
			
			@ -2092,6 +2097,13 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len,
 | 
			
		|||
out:
 | 
			
		||||
	tun_put(tun);
 | 
			
		||||
	return ret;
 | 
			
		||||
 | 
			
		||||
out_put_tun:
 | 
			
		||||
	tun_put(tun);
 | 
			
		||||
out_free_skb:
 | 
			
		||||
	if (skb)
 | 
			
		||||
		kfree_skb(skb);
 | 
			
		||||
	return ret;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int tun_peek_len(struct socket *sock)
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
		Reference in a new issue