From 677f136c6b88ac09a5b1c84dc4473e5901cf218b Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 28 Feb 2019 15:17:28 -0800 Subject: [PATCH] net: support 64bit rates for getsockopt(SO_MAX_PACING_RATE) For legacy applications using 32bit variable, SO_MAX_PACING_RATE has to cap the returned value to 0xFFFFFFFF, meaning that rates above 34.35 Gbit are capped. This patch allows applications to read socket pacing rate at full resolution, if they provide a 64bit variable to store it, and the kernel is 64bit. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/sock.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/net/core/sock.c b/net/core/sock.c index 23aa02ffd6b8..782343bb925b 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1219,6 +1219,7 @@ int sock_getsockopt(struct socket *sock, int level, int optname, union { int val; u64 val64; + unsigned long ulval; struct linger ling; struct old_timeval32 tm32; struct __kernel_old_timeval tm; @@ -1464,8 +1465,13 @@ int sock_getsockopt(struct socket *sock, int level, int optname, #endif case SO_MAX_PACING_RATE: - /* 32bit version */ - v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U); + if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) { + lv = sizeof(v.ulval); + v.ulval = sk->sk_max_pacing_rate; + } else { + /* 32bit version */ + v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U); + } break; case SO_INCOMING_CPU: