[PATCH] ipvs:set sock send/receive buffer correctly

From: linmiaohe
Date: Wed Apr 17 2019 - 05:18:38 EST


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>
---
net/netfilter/ipvs/ip_vs_sync.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index 2526be6b3d90..c0e4cbed6e74 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -1278,14 +1278,12 @@ 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);
+ 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);
+ sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
}
release_sock(sk);
--
2.19.1