From becb74f0acca19b5abfcb24dc602530f3deea66a Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 19 Mar 2015 19:04:21 -0700 Subject: [PATCH] net: increase sk_[max_]ack_backlog sk_ack_backlog & sk_max_ack_backlog were 16bit fields, meaning listen() backlog was limited to 65535. It is time to increase the width to allow much bigger backlog, if admins change /proc/sys/net/core/somaxconn & /proc/sys/net/ipv4/tcp_max_syn_backlog default values. Tested: echo 5000000 >/proc/sys/net/core/somaxconn echo 5000000 >/proc/sys/net/ipv4/tcp_max_syn_backlog Ran a SYNFLOOD test against a listener using listen(fd, 5000000) myhost~# grep request_sock_TCP /proc/slabinfo request_sock_TCP 4185642 4411940 304 13 1 : tunables 54 27 8 : slabdata 339380 339380 0 Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/sock.h | 4 ++-- net/core/sysctl_net_core.c | 2 -- 2 files changed, 2 insertions(+), 4 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index e0360f5a53e9..3f9b8ce56948 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -405,8 +405,8 @@ struct sock { rwlock_t sk_callback_lock; int sk_err, sk_err_soft; - unsigned short sk_ack_backlog; - unsigned short sk_max_ack_backlog; + u32 sk_ack_backlog; + u32 sk_max_ack_backlog; __u32 sk_priority; #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) __u32 sk_cgrp_prioidx; diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index 433424804284..e1c85db5216f 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -24,7 +24,6 @@ static int zero = 0; static int one = 1; -static int ushort_max = USHRT_MAX; static int net_msg_warn; /* Unused, but still a sysctl */ @@ -401,7 +400,6 @@ static struct ctl_table netns_core_table[] = { .maxlen = sizeof(int), .mode = 0644, .extra1 = &zero, - .extra2 = &ushort_max, .proc_handler = proc_dointvec_minmax }, { } -- 2.39.2