| Message ID | 4BDF300B.1040103@simon.arlott.org.uk |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Simon Arlott <simon@fire.lp0.eu> Date: Mon, 03 May 2010 21:20:27 +0100 > Frequently when using PPPoE with an interface MTU greater than 1500, > the skb is likely to be non-linear. If the skb needs to be passed to > pppd then the skb data must be read correctly. > > The previous commit fixes an issue with accidentally sending skbs > to pppd based on an invalid read of the protocol type. When that > error occurred pppd was reading invalid skb data too. > > Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/ppp_generic.c b/drivers/net/ppp_generic.c index 75e8903..8518a2e 100644 --- a/drivers/net/ppp_generic.c +++ b/drivers/net/ppp_generic.c @@ -405,6 +405,7 @@ static ssize_t ppp_read(struct file *file, char __user *buf, DECLARE_WAITQUEUE(wait, current); ssize_t ret; struct sk_buff *skb = NULL; + struct iovec iov; ret = count; @@ -448,7 +449,9 @@ static ssize_t ppp_read(struct file *file, char __user *buf, if (skb->len > count) goto outf; ret = -EFAULT; - if (copy_to_user(buf, skb->data, skb->len)) + iov.iov_base = buf; + iov.iov_len = count; + if (skb_copy_datagram_iovec(skb, 0, &iov, skb->len)) goto outf; ret = skb->len;
Frequently when using PPPoE with an interface MTU greater than 1500, the skb is likely to be non-linear. If the skb needs to be passed to pppd then the skb data must be read correctly. The previous commit fixes an issue with accidentally sending skbs to pppd based on an invalid read of the protocol type. When that error occurred pppd was reading invalid skb data too. Signed-off-by: Simon Arlott <simon@fire.lp0.eu> --- drivers/net/ppp_generic.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)