From 9669fffc1415bb0c30e5d2ec98a8e1c3a418cb9c Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 16 Oct 2019 18:00:56 -0700 Subject: [PATCH] net: ensure correct skb->tstamp in various fragmenters Thomas found that some forwarded packets would be stuck in FQ packet scheduler because their skb->tstamp contained timestamps far in the future. We thought we addressed this point in commit 8203e2d844d3 ("net: clear skb->tstamp in forwarding paths") but there is still an issue when/if a packet needs to be fragmented. In order to meet EDT requirements, we have to make sure all fragments get the original skb->tstamp. Note that this original skb->tstamp should be zero in forwarding path, but might have a non zero value in output path if user decided so. Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC") Signed-off-by: Eric Dumazet Reported-by: Thomas Bartschies Signed-off-by: David S. Miller --- net/bridge/netfilter/nf_conntrack_bridge.c | 3 +++ net/ipv4/ip_output.c | 3 +++ net/ipv6/ip6_output.c | 3 +++ net/ipv6/netfilter.c | 3 +++ 4 files changed, 12 insertions(+) diff --git a/net/bridge/netfilter/nf_conntrack_bridge.c b/net/bridge/netfilter/nf_conntrack_bridge.c index 8842798c29e6..506d6141e44e 100644 --- a/net/bridge/netfilter/nf_conntrack_bridge.c +++ b/net/bridge/netfilter/nf_conntrack_bridge.c @@ -33,6 +33,7 @@ static int nf_br_ip_fragment(struct net *net, struct sock *sk, { int frag_max_size = BR_INPUT_SKB_CB(skb)->frag_max_size; unsigned int hlen, ll_rs, mtu; + ktime_t tstamp = skb->tstamp; struct ip_frag_state state; struct iphdr *iph; int err; @@ -80,6 +81,7 @@ static int nf_br_ip_fragment(struct net *net, struct sock *sk, if (iter.frag) ip_fraglist_prepare(skb, &iter); + skb->tstamp = tstamp; err = output(net, sk, data, skb); if (err || !iter.frag) break; @@ -104,6 +106,7 @@ static int nf_br_ip_fragment(struct net *net, struct sock *sk, goto blackhole; } + skb2->tstamp = tstamp; err = output(net, sk, data, skb2); if (err) goto blackhole; diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 28fca408812c..814b9b8882a0 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -771,6 +771,7 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, struct rtable *rt = skb_rtable(skb); unsigned int mtu, hlen, ll_rs; struct ip_fraglist_iter iter; + ktime_t tstamp = skb->tstamp; struct ip_frag_state state; int err = 0; @@ -846,6 +847,7 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, ip_fraglist_prepare(skb, &iter); } + skb->tstamp = tstamp; err = output(net, sk, skb); if (!err) @@ -900,6 +902,7 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, /* * Put this fragment into the sending queue. */ + skb2->tstamp = tstamp; err = output(net, sk, skb2); if (err) goto fail; diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index edadee4a7e76..71827b56c006 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -768,6 +768,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, inet6_sk(skb->sk) : NULL; struct ip6_frag_state state; unsigned int mtu, hlen, nexthdr_offset; + ktime_t tstamp = skb->tstamp; int hroom, err = 0; __be32 frag_id; u8 *prevhdr, nexthdr = 0; @@ -855,6 +856,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, if (iter.frag) ip6_fraglist_prepare(skb, &iter); + skb->tstamp = tstamp; err = output(net, sk, skb); if (!err) IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), @@ -913,6 +915,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, /* * Put this fragment into the sending queue. */ + frag->tstamp = tstamp; err = output(net, sk, frag); if (err) goto fail; diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index a9bff556d3b2..409e79b84a83 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -119,6 +119,7 @@ int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, struct sk_buff *)) { int frag_max_size = BR_INPUT_SKB_CB(skb)->frag_max_size; + ktime_t tstamp = skb->tstamp; struct ip6_frag_state state; u8 *prevhdr, nexthdr = 0; unsigned int mtu, hlen; @@ -183,6 +184,7 @@ int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, if (iter.frag) ip6_fraglist_prepare(skb, &iter); + skb->tstamp = tstamp; err = output(net, sk, data, skb); if (err || !iter.frag) break; @@ -215,6 +217,7 @@ int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, goto blackhole; } + skb2->tstamp = tstamp; err = output(net, sk, data, skb2); if (err) goto blackhole;