Re: [PATCH] iov_iter: don't revert if csum error

From: Sabrina Dubroca
Date: Fri Apr 28 2017 - 09:17:04 EST


2017-04-28, 20:48:45 +0800, Ding Tianhong wrote:
> The patch 3278682 (make skb_copy_datagram_msg() et.al. preserve
> ->msg_iter on error) will revert the iov buffer if copy to iter
> failed, but it looks no need to revert for csum error, so fix it.
>
> Fixes: 3278682 ("make skb_copy_datagram_msg() et.al. preserve->msg_iter on error")

Please use 12 digits, ie 327868212381.

> Signed-off-by: Ding Tianhong <dingtianhong@xxxxxxxxxx>
> ---
> net/core/datagram.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/core/datagram.c b/net/core/datagram.c
> index f4947e7..475a8e9 100644
> --- a/net/core/datagram.c
> +++ b/net/core/datagram.c
> @@ -760,7 +760,7 @@ int skb_copy_and_csum_datagram_msg(struct sk_buff *skb,
>
> if (msg_data_left(msg) < chunk) {
> if (__skb_checksum_complete(skb))
> - goto csum_error;
> + goto fault;

With this patch, skb_copy_and_csum_datagram_msg() will return -EFAULT
for an incorrect checksum, that doesn't seem right.

> if (skb_copy_datagram_msg(skb, hlen, msg, chunk))
> goto fault;
> } else {
> --
> 1.8.3.1
>

--
Sabrina