From: Michal Kubecek <mkubecek@suse.cz>
Subject: kabi: drop LINUX_MIB_TCPWQUEUETOOBIG snmp counter
Patch-mainline: Never, kabi workaround
References: CVE-2019-11478 bsc#1137586

patches.fixes/tcp-tcp_fragment-should-apply-sane-memory-limits.patch adds
LINUX_MIB_TCPWQUEUETOOBIG snmp attribute which breaks kABI. As it is only
a diagnostic aid and is not essential for the actual security fix, drop
the snmp counter and leave only the check.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
---
 include/uapi/linux/snmp.h | 1 -
 net/ipv4/proc.c           | 1 -
 net/ipv4/tcp_output.c     | 4 +---
 3 files changed, 1 insertion(+), 5 deletions(-)

--- a/include/uapi/linux/snmp.h
+++ b/include/uapi/linux/snmp.h
@@ -275,7 +275,6 @@ enum
 	LINUX_MIB_TCPKEEPALIVE,			/* TCPKeepAlive */
 	LINUX_MIB_TCPMTUPFAIL,			/* TCPMTUPFail */
 	LINUX_MIB_TCPMTUPSUCCESS,		/* TCPMTUPSuccess */
-	LINUX_MIB_TCPWQUEUETOOBIG,		/* TCPWqueueTooBig */
 	__LINUX_MIB_MAX
 };
 
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -297,7 +297,6 @@ static const struct snmp_mib snmp4_net_list[] = {
 	SNMP_MIB_ITEM("TCPKeepAlive", LINUX_MIB_TCPKEEPALIVE),
 	SNMP_MIB_ITEM("TCPMTUPFail", LINUX_MIB_TCPMTUPFAIL),
 	SNMP_MIB_ITEM("TCPMTUPSuccess", LINUX_MIB_TCPMTUPSUCCESS),
-	SNMP_MIB_ITEM("TCPWqueueTooBig", LINUX_MIB_TCPWQUEUETOOBIG),
 	SNMP_MIB_SENTINEL
 };
 
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1282,10 +1282,8 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
 	limit = sk->sk_sndbuf + 2 * SKB_TRUESIZE(GSO_MAX_SIZE);
 	if (unlikely((sk->sk_wmem_queued >> 1) > limit &&
 		     skb != tcp_rtx_queue_head(sk) &&
-		     skb != tcp_rtx_queue_tail(sk))) {
-		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPWQUEUETOOBIG);
+		     skb != tcp_rtx_queue_tail(sk)))
 		return -ENOMEM;
-	}
 
 	if (skb_unclone(skb, gfp))
 		return -ENOMEM;