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 <eduma...@google.com>
Reported-by: Thomas Bartschies <thomas.bartsch...@cvk.de>
---
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
8842798c29e636ac2dbfe01f0bf2ba2f2d398c44..506d6141e44eea67ccc34123ad4250a19bcc7ab7
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
28fca408812c5576fc4ea957c1c4dec97ec8faf3..814b9b8882a0237bffd869cb13739e03af227f30
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
edadee4a7e76105f737d705052db8f5bbc6c0152..71827b56c0063b56bcfbef4bd8910ddcec035824
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
a9bff556d3b2ddd5334d20a63210bad0dfa6cd2d..409e79b84a830dd22ffe7728f45d9dc65ec01df4
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;
--
2.23.0.700.g56cf767bdb-goog
