On 09/15/2018 12:00 PM, YueHaibing 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.
>
Thanks for reporting this issue!
> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
> ---
> 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;
>
Your fix helps, but I would like to follow the hint of Andreas Schwab, and split
the return value check like this:
---
net/smc/smc_clc.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -446,14 +446,12 @@ int smc_clc_send_proposal(struct smc_soc
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 >= 0) {
- reason_code = -ENETUNREACH;
- smc->sk.sk_err = -reason_code;
- } else {
- smc->sk.sk_err = smc->clcsock->sk->sk_err;
- reason_code = -smc->sk.sk_err;
- }
+ if (len < 0) {
+ smc->sk.sk_err = smc->clcsock->sk->sk_err;
+ reason_code = -smc->sk.sk_err;
+ } else if (len < (int)sizeof(pclc)) {
+ reason_code = -ENETUNREACH;
+ smc->sk.sk_err = -reason_code;
}
return reason_code;
Agreed?
Regards, Ursula
