From 3ff50bc627aa309e256f30ae17ac7c69cbc2e94d Mon Sep 17 00:00:00 2001 From: Jamie Bainbridge Date: Tue, 1 Oct 2024 15:04:03 +0000 Subject: [PATCH] icmp: Add counters for rate limits commit d0941130c93515411c8d66fc22bdae407b509a6d upstream. There are multiple ICMP rate limiting mechanisms: * Global limits: net.ipv4.icmp_msgs_burst/icmp_msgs_per_sec * v4 per-host limits: net.ipv4.icmp_ratelimit/ratemask * v6 per-host limits: net.ipv6.icmp_ratelimit/ratemask However, when ICMP output is limited, there is no way to tell which limit has been hit or even if the limits are responsible for the lack of ICMP output. Add counters for each of the cases above. As we are within local_bh_disable(), use the __INC stats variant. Example output: # nstat -sz "*RateLimit*" IcmpOutRateLimitGlobal 134 0.0 IcmpOutRateLimitHost 770 0.0 Icmp6OutRateLimitHost 84 0.0 Signed-off-by: Jamie Bainbridge Suggested-by: Abhishek Rawal Link: https://lore.kernel.org/r/273b32241e6b7fdc5c609e6f5ebc68caf3994342.1674605770.git.jamie.bainbridge@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Eric Dumazet Signed-off-by: Greg Kroah-Hartman --- include/uapi/linux/snmp.h | 3 +++ net/ipv4/icmp.c | 3 +++ net/ipv4/proc.c | 8 +++++--- net/ipv6/icmp.c | 4 ++++ net/ipv6/proc.c | 1 + 5 files changed, 16 insertions(+), 3 deletions(-) diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h index 4d7470036a8b..8ecb509a84d3 100644 --- a/include/uapi/linux/snmp.h +++ b/include/uapi/linux/snmp.h @@ -95,6 +95,8 @@ enum ICMP_MIB_OUTADDRMASKS, /* OutAddrMasks */ ICMP_MIB_OUTADDRMASKREPS, /* OutAddrMaskReps */ ICMP_MIB_CSUMERRORS, /* InCsumErrors */ + ICMP_MIB_RATELIMITGLOBAL, /* OutRateLimitGlobal */ + ICMP_MIB_RATELIMITHOST, /* OutRateLimitHost */ __ICMP_MIB_MAX }; @@ -112,6 +114,7 @@ enum ICMP6_MIB_OUTMSGS, /* OutMsgs */ ICMP6_MIB_OUTERRORS, /* OutErrors */ ICMP6_MIB_CSUMERRORS, /* InCsumErrors */ + ICMP6_MIB_RATELIMITHOST, /* OutRateLimitHost */ __ICMP6_MIB_MAX }; diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 31051b327e53..190988bfa3e2 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -297,6 +297,7 @@ static bool icmpv4_global_allow(struct net *net, int type, int code) if (icmp_global_allow()) return true; + __ICMP_INC_STATS(net, ICMP_MIB_RATELIMITGLOBAL); return false; } @@ -326,6 +327,8 @@ static bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt, if (peer) inet_putpeer(peer); out: + if (!rc) + __ICMP_INC_STATS(net, ICMP_MIB_RATELIMITHOST); return rc; } diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c index 5386f460bd20..1f52c5f2d347 100644 --- a/net/ipv4/proc.c +++ b/net/ipv4/proc.c @@ -352,7 +352,7 @@ static void icmp_put(struct seq_file *seq) seq_puts(seq, "\nIcmp: InMsgs InErrors InCsumErrors"); for (i = 0; icmpmibmap[i].name; i++) seq_printf(seq, " In%s", icmpmibmap[i].name); - seq_puts(seq, " OutMsgs OutErrors"); + seq_puts(seq, " OutMsgs OutErrors OutRateLimitGlobal OutRateLimitHost"); for (i = 0; icmpmibmap[i].name; i++) seq_printf(seq, " Out%s", icmpmibmap[i].name); seq_printf(seq, "\nIcmp: %lu %lu %lu", @@ -362,9 +362,11 @@ static void icmp_put(struct seq_file *seq) for (i = 0; icmpmibmap[i].name; i++) seq_printf(seq, " %lu", atomic_long_read(ptr + icmpmibmap[i].index)); - seq_printf(seq, " %lu %lu", + seq_printf(seq, " %lu %lu %lu %lu", snmp_fold_field(net->mib.icmp_statistics, ICMP_MIB_OUTMSGS), - snmp_fold_field(net->mib.icmp_statistics, ICMP_MIB_OUTERRORS)); + snmp_fold_field(net->mib.icmp_statistics, ICMP_MIB_OUTERRORS), + snmp_fold_field(net->mib.icmp_statistics, ICMP_MIB_RATELIMITGLOBAL), + snmp_fold_field(net->mib.icmp_statistics, ICMP_MIB_RATELIMITHOST)); for (i = 0; icmpmibmap[i].name; i++) seq_printf(seq, " %lu", atomic_long_read(ptr + (icmpmibmap[i].index | 0x100))); diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c index e2af7ab99282..7bea1d82e178 100644 --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -183,6 +183,7 @@ static bool icmpv6_global_allow(struct net *net, int type) if (icmp_global_allow()) return true; + __ICMP_INC_STATS(net, ICMP_MIB_RATELIMITGLOBAL); return false; } @@ -224,6 +225,9 @@ static bool icmpv6_xrlim_allow(struct sock *sk, u8 type, if (peer) inet_putpeer(peer); } + if (!res) + __ICMP6_INC_STATS(net, ip6_dst_idev(dst), + ICMP6_MIB_RATELIMITHOST); dst_release(dst); return res; } diff --git a/net/ipv6/proc.c b/net/ipv6/proc.c index d6306aa46bb1..e20b3705c2d2 100644 --- a/net/ipv6/proc.c +++ b/net/ipv6/proc.c @@ -94,6 +94,7 @@ static const struct snmp_mib snmp6_icmp6_list[] = { SNMP_MIB_ITEM("Icmp6OutMsgs", ICMP6_MIB_OUTMSGS), SNMP_MIB_ITEM("Icmp6OutErrors", ICMP6_MIB_OUTERRORS), SNMP_MIB_ITEM("Icmp6InCsumErrors", ICMP6_MIB_CSUMERRORS), + SNMP_MIB_ITEM("Icmp6OutRateLimitHost", ICMP6_MIB_RATELIMITHOST), SNMP_MIB_SENTINEL };