kernel/linux.git/net/ipv4/ip_forward.c, branch v6.6.131

net: ipv4, ipv6: fix IPSTATS_MIB_OUTOCTETS increment duplicated

2023-08-30T08:44:09+00:00

commit edf391ff1723 ("snmp: add missing counters for RFC 4293") had already added OutOctets for RFC 4293. In commit 2d8dbb04c63e ("snmp: fix OutOctets counter to include forwarded datagrams"), OutOctets was counted again, but not removed from ip_output(). According to RFC 4293 "3.2.3. IP Statistics Tables", ipipIfStatsOutTransmits is not equal to ipIfStatsOutForwDatagrams. So "IPSTATS_MIB_OUTOCTETS must be incremented when incrementing" is not accurate. And IPSTATS_MIB_OUTOCTETS should be counted after fragment. This patch reverts commit 2d8dbb04c63e ("snmp: fix OutOctets counter to include forwarded datagrams") and move IPSTATS_MIB_OUTOCTETS to ip_finish_output2 for ipv4. Reviewed-by: Filip Pudak Signed-off-by: Heng Guo Signed-off-by: David S. Miller

ip: Fix data-races around sysctl_ip_fwd_update_priority.

2022-07-15T10:49:55+00:00

While reading sysctl_ip_fwd_update_priority, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 432e05d32892 ("net: ipv4: Control SKB reprioritization after forwarding") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller

net: ip: add skb drop reasons to ip forwarding

2022-04-13T12:09:57+00:00

Replace kfree_skb() which is used in ip6_forward() and ip_forward() with kfree_skb_reason(). The new drop reason 'SKB_DROP_REASON_PKT_TOO_BIG' is introduced for the case that the length of the packet exceeds MTU and can't fragment. Signed-off-by: Menglong Dong Reviewed-by: Jiang Biao Reviewed-by: Hao Peng Signed-off-by: David S. Miller

net: Add skb_clear_tstamp() to keep the mono delivery_time

2022-03-03T14:38:48+00:00

Right now, skb->tstamp is reset to 0 whenever the skb is forwarded. If skb->tstamp has the mono delivery_time, clearing it can hurt the performance when it finally transmits out to fq@phy-dev. The earlier patch added a skb->mono_delivery_time bit to flag the skb->tstamp carrying the mono delivery_time. This patch adds skb_clear_tstamp() helper which keeps the mono delivery_time and clears everything else. The delivery_time clearing will be postponed until the stack knows the skb will be delivered locally. It will be done in a latter patch. Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller

ipv4: Revert removal of rt_uses_gateway

2019-09-21T01:23:33+00:00

Julian noted that rt_uses_gateway has a more subtle use than 'is gateway set': https://lore.kernel.org/netdev/alpine.LFD.2.21.1909151104060.2546@ja.home.ssi.bg/ Revert that part of the commit referenced in the Fixes tag. Currently, there are no u8 holes in 'struct rtable'. There is a 4-byte hole in the second cacheline which contains the gateway declaration. So move rt_gw_family down to the gateway declarations since they are always used together, and then re-use that u8 for rt_uses_gateway. End result is that rtable size is unchanged. Fixes: 1550c171935d ("ipv4: Prepare rtable for IPv6 gateway") Reported-by: Julian Anastasov Signed-off-by: David Ahern Reviewed-by: Julian Anastasov Signed-off-by: Jakub Kicinski

ipv4: Prepare rtable for IPv6 gateway

2019-04-08T22:22:40+00:00

To allow the gateway to be either an IPv4 or IPv6 address, remove rt_uses_gateway from rtable and replace with rt_gw_family. If rt_gw_family is set it implies rt_uses_gateway. Rename rt_gateway to rt_gw4 to represent the IPv4 version. Signed-off-by: David Ahern Reviewed-by: Ido Schimmel Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2018-12-20T19:53:36+00:00

Lots of conflicts, by happily all cases of overlapping changes, parallel adds, things of that nature. Thanks to Stephen Rothwell, Saeed Mahameed, and others for their guidance in these resolutions. Signed-off-by: David S. Miller

net: clear skb->tstamp in forwarding paths

2018-12-15T21:24:21+00:00

Sergey reported that forwarding was no longer working if fq packet scheduler was used. This is caused by the recent switch to EDT model, since incoming packets might have been timestamped by __net_timestamp() __net_timestamp() uses ktime_get_real(), while fq expects packets using CLOCK_MONOTONIC base. The fix is to clear skb->tstamp in forwarding paths. Fixes: 80b14dee2bea ("net: Add a new socket option for a future transmit time.") Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC") Signed-off-by: Eric Dumazet Reported-by: Sergey Matyukevich Tested-by: Sergey Matyukevich Signed-off-by: David S. Miller

net: Do not route unicast IP packets twice

2018-12-04T16:36:36+00:00

Packets marked with 'offload_l3_fwd_mark' were already forwarded by a capable device and should not be forwarded again by the kernel. Therefore, have the kernel consume them. The check is performed in ip{,6}_forward_finish() in order to allow the kernel to process such packets in ip{,6}_forward() and generate required exceptions. For example, ICMP redirects. Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller

net: ipv4: Control SKB reprioritization after forwarding

2018-08-01T16:52:30+00:00

After IPv4 packets are forwarded, the priority of the corresponding SKB is updated according to the TOS field of IPv4 header. This overrides any prioritization done earlier by e.g. an skbedit action or ingress-qos-map defined at a vlan device. Such overriding may not always be desirable. Even if the packet ends up being routed, which implies this is an L3 network node, an administrator may wish to preserve whatever prioritization was done earlier on in the pipeline. Therefore introduce a sysctl that controls this behavior. Keep the default value at 1 to maintain backward-compatible behavior. Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel Signed-off-by: David S. Miller