6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Heng Guo <heng.guo@xxxxxxxxxxxxx> commit b4a11b2033b7d3dfdd46592f7036a775b18cecd1 upstream. Reproduce environment: network with 3 VM linuxs is connected as below: VM1<---->VM2(latest kernel 6.5.0-rc7)<---->VM3 VM1: eth0 ip: 192.168.122.207 MTU 1500 VM2: eth0 ip: 192.168.122.208, eth1 ip: 192.168.123.224 MTU 1500 VM3: eth0 ip: 192.168.123.240 MTU 1500 Reproduce: VM1 send 1400 bytes UDP data to VM3 using tools scapy with flags=0. scapy command: send(IP(dst="192.168.123.240",flags=0)/UDP()/str('0'*1400),count=1, inter=1.000000) Result: Before IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates Ip: 1 64 11 0 3 4 0 0 4 7 0 0 0 0 0 0 0 0 0 ...... ---------------------------------------------------------------------- After IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates Ip: 1 64 12 0 3 5 0 0 4 8 0 0 0 0 0 0 0 0 0 ...... ---------------------------------------------------------------------- "ForwDatagrams" increase from 4 to 5 and "OutRequests" also increase from 7 to 8. Issue description and patch: IPSTATS_MIB_OUTPKTS("OutRequests") is counted with IPSTATS_MIB_OUTOCTETS ("OutOctets") in ip_finish_output2(). According to RFC 4293, it is "OutOctets" counted with "OutTransmits" but not "OutRequests". "OutRequests" does not include any datagrams counted in "ForwDatagrams". ipSystemStatsOutOctets OBJECT-TYPE DESCRIPTION "The total number of octets in IP datagrams delivered to the lower layers for transmission. Octets from datagrams counted in ipIfStatsOutTransmits MUST be counted here. ipSystemStatsOutRequests OBJECT-TYPE DESCRIPTION "The total number of IP datagrams that local IP user- protocols (including ICMP) supplied to IP in requests for transmission. Note that this counter does not include any datagrams counted in ipSystemStatsOutForwDatagrams. So do patch to define IPSTATS_MIB_OUTPKTS to "OutTransmits" and add IPSTATS_MIB_OUTREQUESTS for "OutRequests". Add IPSTATS_MIB_OUTREQUESTS counter in __ip_local_out() for ipv4 and add IPSTATS_MIB_OUT counter in ip6_finish_output2() for ipv6. Test result with patch: Before IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates OutTransmits Ip: 1 64 9 0 5 1 0 0 3 3 0 0 0 0 0 0 0 0 0 4 ...... root@qemux86-64:~# cat /proc/net/netstat ...... IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts InECT0Pkts InCEPkts ReasmOverlaps IpExt: 0 0 0 0 0 0 2976 1896 0 0 0 0 0 9 0 0 0 0 ---------------------------------------------------------------------- After IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates OutTransmits Ip: 1 64 10 0 5 2 0 0 3 3 0 0 0 0 0 0 0 0 0 5 ...... root@qemux86-64:~# cat /proc/net/netstat ...... IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts InECT0Pkts InCEPkts ReasmOverlaps IpExt: 0 0 0 0 0 0 4404 3324 0 0 0 0 0 10 0 0 0 0 ---------------------------------------------------------------------- "ForwDatagrams" increase from 1 to 2 and "OutRequests" is keeping 3. "OutTransmits" increase from 4 to 5 and "OutOctets" increase 1428. Signed-off-by: Heng Guo <heng.guo@xxxxxxxxxxxxx> Reviewed-by: Kun Song <Kun.Song@xxxxxxxxxxxxx> Reviewed-by: Filip Pudak <filip.pudak@xxxxxxxxxxxxx> Reviewed-by: David Ahern <dsahern@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Reported-by: Vitezslav Samel <vitezslav@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/uapi/linux/snmp.h | 3 ++- net/ipv4/ip_output.c | 2 ++ net/ipv4/proc.c | 3 ++- net/ipv6/ip6_output.c | 6 ++++-- net/ipv6/mcast.c | 5 ++--- net/ipv6/ndisc.c | 2 +- net/ipv6/proc.c | 3 ++- net/ipv6/raw.c | 2 +- 8 files changed, 16 insertions(+), 10 deletions(-) --- a/include/uapi/linux/snmp.h +++ b/include/uapi/linux/snmp.h @@ -24,7 +24,7 @@ enum IPSTATS_MIB_INOCTETS, /* InOctets */ IPSTATS_MIB_INDELIVERS, /* InDelivers */ IPSTATS_MIB_OUTFORWDATAGRAMS, /* OutForwDatagrams */ - IPSTATS_MIB_OUTPKTS, /* OutRequests */ + IPSTATS_MIB_OUTREQUESTS, /* OutRequests */ IPSTATS_MIB_OUTOCTETS, /* OutOctets */ /* other fields */ IPSTATS_MIB_INHDRERRORS, /* InHdrErrors */ @@ -57,6 +57,7 @@ enum IPSTATS_MIB_ECT0PKTS, /* InECT0Pkts */ IPSTATS_MIB_CEPKTS, /* InCEPkts */ IPSTATS_MIB_REASM_OVERLAPS, /* ReasmOverlaps */ + IPSTATS_MIB_OUTPKTS, /* OutTransmits */ __IPSTATS_MIB_MAX }; --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -101,6 +101,8 @@ int __ip_local_out(struct net *net, stru { struct iphdr *iph = ip_hdr(skb); + IP_INC_STATS(net, IPSTATS_MIB_OUTREQUESTS); + iph_set_totlen(iph, skb->len); ip_send_check(iph); --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -83,7 +83,7 @@ static const struct snmp_mib snmp4_ipsta SNMP_MIB_ITEM("InUnknownProtos", IPSTATS_MIB_INUNKNOWNPROTOS), SNMP_MIB_ITEM("InDiscards", IPSTATS_MIB_INDISCARDS), SNMP_MIB_ITEM("InDelivers", IPSTATS_MIB_INDELIVERS), - SNMP_MIB_ITEM("OutRequests", IPSTATS_MIB_OUTPKTS), + SNMP_MIB_ITEM("OutRequests", IPSTATS_MIB_OUTREQUESTS), SNMP_MIB_ITEM("OutDiscards", IPSTATS_MIB_OUTDISCARDS), SNMP_MIB_ITEM("OutNoRoutes", IPSTATS_MIB_OUTNOROUTES), SNMP_MIB_ITEM("ReasmTimeout", IPSTATS_MIB_REASMTIMEOUT), @@ -93,6 +93,7 @@ static const struct snmp_mib snmp4_ipsta SNMP_MIB_ITEM("FragOKs", IPSTATS_MIB_FRAGOKS), SNMP_MIB_ITEM("FragFails", IPSTATS_MIB_FRAGFAILS), SNMP_MIB_ITEM("FragCreates", IPSTATS_MIB_FRAGCREATES), + SNMP_MIB_ITEM("OutTransmits", IPSTATS_MIB_OUTPKTS), SNMP_MIB_SENTINEL }; --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -117,6 +117,8 @@ static int ip6_finish_output2(struct net return res; } + IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); + rcu_read_lock(); nexthop = rt6_nexthop((struct rt6_info *)dst, daddr); neigh = __ipv6_neigh_lookup_noref(dev, nexthop); @@ -335,7 +337,7 @@ int ip6_xmit(const struct sock *sk, stru mtu = dst_mtu(dst); if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) { - IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); + IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS); /* if egress device is enslaved to an L3 master device pass the * skb to its handler for processing @@ -1995,7 +1997,7 @@ struct sk_buff *__ip6_make_skb(struct so skb->tstamp = cork->base.transmit_time; ip6_cork_steal_dst(skb, cork); - IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len); + IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS); if (proto == IPPROTO_ICMPV6) { struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb)); u8 icmp6_type; --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -1789,7 +1789,7 @@ static void mld_sendpack(struct sk_buff rcu_read_lock(); idev = __in6_dev_get(skb->dev); - IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); + IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS); payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) - sizeof(*pip6); @@ -2147,8 +2147,7 @@ static void igmp6_send(struct in6_addr * full_len = sizeof(struct ipv6hdr) + payload_len; rcu_read_lock(); - IP6_UPD_PO_STATS(net, __in6_dev_get(dev), - IPSTATS_MIB_OUT, full_len); + IP6_INC_STATS(net, __in6_dev_get(dev), IPSTATS_MIB_OUTREQUESTS); rcu_read_unlock(); skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err); --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -504,7 +504,7 @@ void ndisc_send_skb(struct sk_buff *skb, rcu_read_lock(); idev = __in6_dev_get(dst->dev); - IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); + IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS); err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb, NULL, dst->dev, --- a/net/ipv6/proc.c +++ b/net/ipv6/proc.c @@ -61,7 +61,7 @@ static const struct snmp_mib snmp6_ipsta SNMP_MIB_ITEM("Ip6InDiscards", IPSTATS_MIB_INDISCARDS), SNMP_MIB_ITEM("Ip6InDelivers", IPSTATS_MIB_INDELIVERS), SNMP_MIB_ITEM("Ip6OutForwDatagrams", IPSTATS_MIB_OUTFORWDATAGRAMS), - SNMP_MIB_ITEM("Ip6OutRequests", IPSTATS_MIB_OUTPKTS), + SNMP_MIB_ITEM("Ip6OutRequests", IPSTATS_MIB_OUTREQUESTS), SNMP_MIB_ITEM("Ip6OutDiscards", IPSTATS_MIB_OUTDISCARDS), SNMP_MIB_ITEM("Ip6OutNoRoutes", IPSTATS_MIB_OUTNOROUTES), SNMP_MIB_ITEM("Ip6ReasmTimeout", IPSTATS_MIB_REASMTIMEOUT), @@ -84,6 +84,7 @@ static const struct snmp_mib snmp6_ipsta SNMP_MIB_ITEM("Ip6InECT1Pkts", IPSTATS_MIB_ECT1PKTS), SNMP_MIB_ITEM("Ip6InECT0Pkts", IPSTATS_MIB_ECT0PKTS), SNMP_MIB_ITEM("Ip6InCEPkts", IPSTATS_MIB_CEPKTS), + SNMP_MIB_ITEM("Ip6OutTransmits", IPSTATS_MIB_OUTPKTS), SNMP_MIB_SENTINEL }; --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -651,7 +651,7 @@ static int rawv6_send_hdrinc(struct sock * have been queued for deletion. */ rcu_read_lock(); - IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len); + IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS); err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb, NULL, rt->dst.dev, dst_output); if (err > 0)