Re: [PATCH] tcp_vu: Change 'dlen' to ssize_t in tcp_vu_data_from_sock()

[Laurent Vivier <lvivier@redhat.com>]

On 27/11/2024 15:43, Stefano Brivio wrote:
> ...to quickly suppress a false positive from Coverity, which assumes
> that iov_size is 0 and 'dlen' might overflow as a result (with hdrlen
> being 66). An ASSERT() in tcp_vu_sock_recv() already guarantees that
> iov_size(iov, buf_cnt) here is anyway greater than 'hdrlen'.
> 
> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
> ---
> This applies on top of "[PATCH] Fix build on 32bit target"
> 
>   tcp_vu.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tcp_vu.c b/tcp_vu.c
> index 05e2d1d..a1510d9 100644
> --- a/tcp_vu.c
> +++ b/tcp_vu.c
> @@ -462,7 +462,7 @@ int tcp_vu_data_from_sock(const struct ctx *c, struct tcp_tap_conn *conn)
>   	for (i = 0, check = NULL; i < head_cnt; i++) {
>   		struct iovec *iov = &elem[head[i]].in_sg[0];
>   		int buf_cnt = head[i + 1] - head[i];
> -		int dlen = iov_size(iov, buf_cnt) - hdrlen;
> +		ssize_t dlen = iov_size(iov, buf_cnt) - hdrlen;
>   
>   		vu_set_vnethdr(vdev, iov->iov_base, buf_cnt);
>   

Reviewed-by: Laurent Vivier <lvivier@redhat.com>