Hello,
On Thu, 18 Apr 2019, linmiaohe wrote:
> From: Jie Liu <liujie165@xxxxxxxxxx>
>
> If we set sysctl_wmem_max or sysctl_rmem_max larger than INT_MAX, the
> send/receive buffer of sock will be an negative value. Same as when
> the val is larger than INT_MAX/2.
>
> Fixes: 1c003b1580e2 ("ipvs: wakeup master thread")
> Reported-by: Qiang Ning <ningqiang1@xxxxxxxxxx>
> Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> Signed-off-by: Jie Liu <liujie165@xxxxxxxxxx>
Looks good to me, thanks!
Acked-by: Julian Anastasov <ja@xxxxxx>
> ---
> net/netfilter/ipvs/ip_vs_sync.c | 20 ++++++++++++++------
> 1 file changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
> index 2526be6b3d90..760f3364d4a2 100644
> --- a/net/netfilter/ipvs/ip_vs_sync.c
> +++ b/net/netfilter/ipvs/ip_vs_sync.c
> @@ -1278,14 +1278,22 @@ static void set_sock_size(struct sock *sk, int mode, int val)
> /* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
> lock_sock(sk);
> if (mode) {
> - val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
> - sysctl_wmem_max);
> - sk->sk_sndbuf = val * 2;
> + val = min_t(u32, val, sysctl_wmem_max);
> +
> + /* Ensure val * 2 fits into an int, to prevent max_t()
> + * from treating it as a negative value.
> + */
> + val = min_t(int, val, INT_MAX / 2);
> + sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
> sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
> } else {
> - val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
> - sysctl_rmem_max);
> - sk->sk_rcvbuf = val * 2;
> + val = min_t(u32, val, sysctl_rmem_max);
> +
> + /* Ensure val * 2 fits into an int, to prevent max_t()
> + * from treating it as a negative value.
> + */
> + val = min_t(int, val, INT_MAX / 2);
> + sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
> sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
> }
> release_sock(sk);
> --
Regards
--
Julian Anastasov <ja@xxxxxx>
