Subject: Re: [PATCH net-next] net/smc: cast sizeof to int for comparison

From: Andreas Schwab <[email-masked]>
Date: Sat, 15 Sep 2018 13:35:32 +0200

On Sep 15 2018, YueHaibing <[email-masked]> wrote:

> Comparing an int to a size, which is unsigned, causes the int to become
> unsigned, giving the wrong result. kernel_sendmsg can return a negative
> error code.
>
> Signed-off-by: YueHaibing <[email-masked]>
> ---
>  net/smc/smc_clc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
> index 83aba9a..fd0f5ce 100644
> --- a/net/smc/smc_clc.c
> +++ b/net/smc/smc_clc.c
> @@ -446,7 +446,7 @@ int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
>  	vec[i++].iov_len = sizeof(trl);
>  	/* due to the few bytes needed for clc-handshake this cannot block */
>  	len = kernel_sendmsg(smc->clcsock, &msg, vec, i, plen);
> -	if (len < sizeof(pclc)) {
> +	if (len < (int)sizeof(pclc)) {
>  		if (len >= 0) {
>  			reason_code = -ENETUNREACH;
>  			smc->sk.sk_err = -reason_code;

It would perhaps be better to handle len < 0 first.

Andreas.

-- 
Andreas Schwab, [email-masked]
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."