[PATCH net v3] ipv6:flush ipv6 route cache when rule is changed

[PATCH net v3] ipv6:flush ipv6 route cache when rule is changed

[Lena Wang (王娜)]

From: Shiming Cheng <shiming.cheng@mediatek.com>

When rule policy is changed, ipv6 socket cache is not refreshed.
The sock's skb still uses a outdated route cache and was sent to
a wrong interface.

To avoid this error we should update fib node's version when
rule is changed. Then skb's route will be reroute checked as
route cache version is already different with fib node version.
The route cache is refreshed to match the latest rule.

Signed-off-by: Shiming Cheng <shiming.cheng@mediatek.com>
Signed-off-by: Lena Wang <lena.wang@mediatek.com>
---
v3: Changes according to Jiri's suggestions, update patch
description and name format in commit message.

v2: Changes according to David Ahern's suggestions, modify
flush function same way as ipv4 flush cache and use tabs
to aligh with existing code.
---
---
 net/ipv6/fib6_rules.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index 7523c4baef35..52c04f0ac498 100644
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -449,6 +449,11 @@ static size_t fib6_rule_nlmsg_payload(struct
fib_rule *rule)
 	       + nla_total_size(16); /* src */
 }
 
+static void fib6_rule_flush_cache(struct fib_rules_ops *ops)
+{
+	rt_genid_bump_ipv6(ops->fro_net);
+}
+
 static const struct fib_rules_ops __net_initconst
fib6_rules_ops_template = {
 	.family			= AF_INET6,
 	.rule_size		= sizeof(struct fib6_rule),
@@ -461,6 +466,7 @@ static const struct fib_rules_ops __net_initconst
fib6_rules_ops_template = {
 	.compare		= fib6_rule_compare,
 	.fill			= fib6_rule_fill,
 	.nlmsg_payload		= fib6_rule_nlmsg_payload,
+	.flush_cache		= fib6_rule_flush_cache,
 	.nlgroup		= RTNLGRP_IPV6_RULE,
 	.owner			= THIS_MODULE,
 	.fro_net		= &init_net,
-- 
2.18.0

Re: [PATCH net v3] ipv6:flush ipv6 route cache when rule is changed

[Jiri Pirko]

Wed, Feb 28, 2024 at 04:38:56PM CET, Lena.Wang@mediatek.com wrote:
>From: Shiming Cheng <shiming.cheng@mediatek.com>
>
>When rule policy is changed, ipv6 socket cache is not refreshed.
>The sock's skb still uses a outdated route cache and was sent to
>a wrong interface.
>
>To avoid this error we should update fib node's version when
>rule is changed. Then skb's route will be reroute checked as
>route cache version is already different with fib node version.
>The route cache is refreshed to match the latest rule.
>
>Signed-off-by: Shiming Cheng <shiming.cheng@mediatek.com>
>Signed-off-by: Lena Wang <lena.wang@mediatek.com>

1) You are still missing Fixes tags, I don't know what to say.
2) Re patch subject:
   "ipv6:flush ipv6 route cache when rule is changed"
   Could it be:
   "ipv6: fib6_rules: flush route cache when rule is changed"
   ? please.
3) Could you please honor the 24h hours resubmission rule:
https://www.kernel.org/doc/html/v6.6/process/maintainer-netdev.html#tl-dr

pw-bot: cr

Re: [PATCH net v3] ipv6:flush ipv6 route cache when rule is changed

[Lena Wang (王娜)]

On Wed, 2024-02-28 at 16:50 +0100, Jiri Pirko wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  Wed, Feb 28, 2024 at 04:38:56PM CET, Lena.Wang@mediatek.com wrote:
> >From: Shiming Cheng <shiming.cheng@mediatek.com>
> >
> >When rule policy is changed, ipv6 socket cache is not refreshed.
> >The sock's skb still uses a outdated route cache and was sent to
> >a wrong interface.
> >
> >To avoid this error we should update fib node's version when
> >rule is changed. Then skb's route will be reroute checked as
> >route cache version is already different with fib node version.
> >The route cache is refreshed to match the latest rule.
> >
> >Signed-off-by: Shiming Cheng <shiming.cheng@mediatek.com>
> >Signed-off-by: Lena Wang <lena.wang@mediatek.com>
> 
> 1) You are still missing Fixes tags, I don't know what to say.
I am sorry for the confuse. My previous change log of fix tag is a
wrong description for "PATCH net v2".

Current patch doesn't fix previous commit. It is more like missing
flush since the first commit 101367c2f8c4 of creating fib6_rules.c. Is
it OK to add this fix or omit fix tag?

> 2) Re patch subject:
>    "ipv6:flush ipv6 route cache when rule is changed"
>    Could it be:
>    "ipv6: fib6_rules: flush route cache when rule is changed"
>    ? please.
Yes, I will update later in v4.

> 3) Could you please honor the 24h hours resubmission rule:
> 
https://www.kernel.org/doc/html/v6.6/process/maintainer-netdev.html#tl-dr
> 
OK. I will follow the rule later.

> pw-bot: cr

Re: [PATCH net v3] ipv6:flush ipv6 route cache when rule is changed

[Jiri Pirko]

Thu, Feb 29, 2024 at 09:24:54AM CET, Lena.Wang@mediatek.com wrote:
>On Wed, 2024-02-28 at 16:50 +0100, Jiri Pirko wrote:
>>  	 
>> External email : Please do not click links or open attachments until
>> you have verified the sender or the content.
>>  Wed, Feb 28, 2024 at 04:38:56PM CET, Lena.Wang@mediatek.com wrote:
>> >From: Shiming Cheng <shiming.cheng@mediatek.com>
>> >
>> >When rule policy is changed, ipv6 socket cache is not refreshed.
>> >The sock's skb still uses a outdated route cache and was sent to
>> >a wrong interface.
>> >
>> >To avoid this error we should update fib node's version when
>> >rule is changed. Then skb's route will be reroute checked as
>> >route cache version is already different with fib node version.
>> >The route cache is refreshed to match the latest rule.
>> >
>> >Signed-off-by: Shiming Cheng <shiming.cheng@mediatek.com>
>> >Signed-off-by: Lena Wang <lena.wang@mediatek.com>
>> 
>> 1) You are still missing Fixes tags, I don't know what to say.
>I am sorry for the confuse. My previous change log of fix tag is a
>wrong description for "PATCH net v2".
>
>Current patch doesn't fix previous commit. It is more like missing
>flush since the first commit 101367c2f8c4 of creating fib6_rules.c. Is
>it OK to add this fix or omit fix tag?

No, the "Fixes" tag needs to be present. In this case, it looks like:
Fixes: 101367c2f8c4 ("[IPV6]: Policy Routing Rules")
Is the appropriate one. Isn't it?

>
>> 2) Re patch subject:
>>    "ipv6:flush ipv6 route cache when rule is changed"
>>    Could it be:
>>    "ipv6: fib6_rules: flush route cache when rule is changed"
>>    ? please.
>Yes, I will update later in v4.
>
>> 3) Could you please honor the 24h hours resubmission rule:
>> 
>https://www.kernel.org/doc/html/v6.6/process/maintainer-netdev.html#tl-dr
>> 
>OK. I will follow the rule later.
>
>> pw-bot: cr

Re: [PATCH net v3] ipv6:flush ipv6 route cache when rule is changed

[Lena Wang (王娜)]

On Thu, 2024-02-29 at 09:39 +0100, Jiri Pirko wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  Thu, Feb 29, 2024 at 09:24:54AM CET, Lena.Wang@mediatek.com wrote:
> >On Wed, 2024-02-28 at 16:50 +0100, Jiri Pirko wrote:
> >>   
> >> External email : Please do not click links or open attachments
> until
> >> you have verified the sender or the content.
> >>  Wed, Feb 28, 2024 at 04:38:56PM CET, Lena.Wang@mediatek.com
> wrote:
> >> >From: Shiming Cheng <shiming.cheng@mediatek.com>
> >> >
> >> >When rule policy is changed, ipv6 socket cache is not refreshed.
> >> >The sock's skb still uses a outdated route cache and was sent to
> >> >a wrong interface.
> >> >
> >> >To avoid this error we should update fib node's version when
> >> >rule is changed. Then skb's route will be reroute checked as
> >> >route cache version is already different with fib node version.
> >> >The route cache is refreshed to match the latest rule.
> >> >
> >> >Signed-off-by: Shiming Cheng <shiming.cheng@mediatek.com>
> >> >Signed-off-by: Lena Wang <lena.wang@mediatek.com>
> >> 
> >> 1) You are still missing Fixes tags, I don't know what to say.
> >I am sorry for the confuse. My previous change log of fix tag is a
> >wrong description for "PATCH net v2".
> >
> >Current patch doesn't fix previous commit. It is more like missing
> >flush since the first commit 101367c2f8c4 of creating fib6_rules.c.
> Is
> >it OK to add this fix or omit fix tag?
> 
> No, the "Fixes" tag needs to be present. In this case, it looks like:
> Fixes: 101367c2f8c4 ("[IPV6]: Policy Routing Rules")
> Is the appropriate one. Isn't it?
> 
OK, I will update it later in v4.
Many thanks.

> >
> >> 2) Re patch subject:
> >>    "ipv6:flush ipv6 route cache when rule is changed"
> >>    Could it be:
> >>    "ipv6: fib6_rules: flush route cache when rule is changed"
> >>    ? please.
> >Yes, I will update later in v4.
> >
> >> 3) Could you please honor the 24h hours resubmission rule:
> >> 
> >
> https://www.kernel.org/doc/html/v6.6/process/maintainer-netdev.html#tl-dr
> >> 
> >OK. I will follow the rule later.
> >
> >> pw-bot: cr