[PATCH] Net:cache didn't flush when ipv6 rule changed

[PATCH] Net:cache didn't flush when ipv6 rule changed

[Lena Wang (王娜)]

From a415abaf4fc90a27dd86357ea8be62d32956f7d8 Mon Sep 17 00:00:00 2001
From: shiming cheng <shiming.cheng@mediatek.com>
Date: Mon, 26 Feb 2024 20:17:58 +0800
Subject: [PATCH] Net:cache didn't flush when ipv6 rule changed

When changed from old rule&route configure to new one as below,
ipv6 cache dst_entry did not change to new route table as no
cache flush callback function, then forward to wrong out interface.
When fib6_check dst_entry, the fib6_node version[fn_sernm] is
always the same with socket dst_cookie, old cache dst_entry is
always used and no chance to update.

So we need to update fib6_node version when rule changed and
flush cache to avoid dispatching a wrong interface.

Signed-off-by: shiming cheng <shiming.cheng@mediatek.com>
---
 net/ipv6/fib6_rules.c | 10 ++++++++++
 1 files changed, 10 insertions(+)

diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index 7523c4baef35..bec2cf4436e1 100644
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -449,6 +449,15 @@ 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)
+{
+       struct net *net = ops->fro_net;
+       if (!net)
+               return;
+       rt_genid_bump_ipv6(net);
+       return;
+}
+
 static const struct fib_rules_ops __net_initconst
fib6_rules_ops_template = {
        .family                 = AF_INET6,
        .rule_size              = sizeof(struct fib6_rule),
@@ -461,6 +470,7 @@ 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:cache didn't flush when ipv6 rule changed

[David Ahern]

On 2/26/24 6:11 AM, Lena Wang (王娜) wrote:

> diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
> index 7523c4baef35..bec2cf4436e1 100644
> --- a/net/ipv6/fib6_rules.c
> +++ b/net/ipv6/fib6_rules.c
> @@ -449,6 +449,15 @@ 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)
> +{
> +       struct net *net = ops->fro_net;
> +       if (!net)
> +               return;
> +       rt_genid_bump_ipv6(net);
> +       return;
> +}

This can be written as a 1-liner - the same way as the IPv4 flush cache:

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 +470,7 @@ 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,

this should be tabs and the columns should align with existing code.



>         .nlgroup                = RTNLGRP_IPV6_RULE,
>         .owner                  = THIS_MODULE,
>         .fro_net                = &init_net,
> --
> 2.18.0

Re: [PATCH] Net:cache didn't flush when ipv6 rule changed

[Lena Wang (王娜)]

On Tue, 2024-02-27 at 08:06 -0700, David Ahern wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  On 2/26/24 6:11 AM, Lena Wang (王娜) wrote:
> 
> > diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
> > index 7523c4baef35..bec2cf4436e1 100644
> > --- a/net/ipv6/fib6_rules.c
> > +++ b/net/ipv6/fib6_rules.c
> > @@ -449,6 +449,15 @@ 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)
> > +{
> > +       struct net *net = ops->fro_net;
> > +       if (!net)
> > +               return;
> > +       rt_genid_bump_ipv6(net);
> > +       return;
> > +}
> 
> This can be written as a 1-liner - the same way as the IPv4 flush
> cache:
> 
> 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 +470,7 @@ 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,
> 
> this should be tabs and the columns should align with existing code.
> 
> 
> 
> >         .nlgroup                = RTNLGRP_IPV6_RULE,
> >         .owner                  = THIS_MODULE,
> >         .fro_net                = &init_net,
> > --
> > 2.18.0
> 

Dear David,
Update the patch as below, thanks.


From db01a40e45f51d00cb19e45a41507c97363d6ed8 Mon Sep 17 00:00:00 2001
From: shiming cheng <shiming.cheng@mediatek.com>
Date: Mon, 26 Feb 2024 20:17:58 +0800
Subject: [PATCH] Net:cache didn't flush when ipv6 rule changed

When changed from old rule&route configure to new one as below,
ipv6 cache dst_entry did not change to new route table as no
cache flush callback function, then forward to wrong out interface.
When fib6_check dst_entry, the fib6_node version[fn_sernm] is
always the same with socket dst_cookie, old cache dst_entry is
always used and no chance to update.

So we need to update fib6_node version when rule changed and
flush cache to avoid dispatching a wrong interface.

Signed-off-by: shiming cheng <shiming.cheng@mediatek.com>
---
 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..31d6183221a2 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(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:cache didn't flush when ipv6 rule changed

[Paolo Abeni]

Hi,

On Wed, 2024-02-28 at 07:28 +0000, Lena Wang (王娜) wrote:
> Dear David,
> Update the patch as below, thanks.
> 
> 
> From db01a40e45f51d00cb19e45a41507c97363d6ed8 Mon Sep 17 00:00:00 2001
> From: shiming cheng <shiming.cheng@mediatek.com>
> Date: Mon, 26 Feb 2024 20:17:58 +0800
> Subject: [PATCH] Net:cache didn't flush when ipv6 rule changed
> 
> When changed from old rule&route configure to new one as below,
> ipv6 cache dst_entry did not change to new route table as no
> cache flush callback function, then forward to wrong out interface.
> When fib6_check dst_entry, the fib6_node version[fn_sernm] is
> always the same with socket dst_cookie, old cache dst_entry is
> always used and no chance to update.
> 
> So we need to update fib6_node version when rule changed and
> flush cache to avoid dispatching a wrong interface.
> 
> Signed-off-by: shiming cheng <shiming.cheng@mediatek.com>

You need to cc the netdev mailing list to allow up processing the
patch.

Please also include the target tree in the subject prefix ('net' in
this case), a suitable fixes tag and avoid sending patches in reply to
existing threads as it confuses our bot.

@David (out of sheer ignorace) could this the root cause for the fib6
self-tests sporadic failures?

Thanks,

Paolo

[PATCH net v2] Net:cache didn't flush when ipv6 rule changed

[Lena Wang (王娜)]

From bf53859b379a653eec8a14fbb3f29286f9f888fb Mon Sep 17 00:00:00 2001
From: shiming cheng <shiming.cheng@mediatek.com>
Date: Mon, 26 Feb 2024 20:17:58 +0800
Subject: [PATCH net v2] Net:cache didn't flush when ipv6 rule changed

When changed from old rule&route configure to new one as below,
ipv6 cache dst_entry did not change to new route table as no
cache flush callback function, then forward to wrong out interface.
When fib6_check dst_entry, the fib6_node version[fn_sernm] is
always the same with socket dst_cookie, old cache dst_entry is
always used and no chance to update.

So we need to update fib6_node version when rule changed and
flush cache to avoid dispatching a wrong interface.

Signed-off-by: shiming cheng <shiming.cheng@mediatek.com>
---
v2: 
    1. Add the fix tag.
    2. Changes according to David Ahern's suggestions, modify flush
functions 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 v2] Net:cache didn't flush when ipv6 rule changed

[Jiri Pirko]

[PATCH net v2] Net:cache didn't flush when ipv6 rule changed

Please make sure your patch subject is aligned with the rest:
$ git log --no-merges --pretty=format:"%s" net/ipv6/fib6_rules.c | head -n30
fib: remove unnecessary input parameters in fib_default_rule_add
ipv6: change fib6_rules_net_exit() to batch mode
ipv6: Define dscp_t and stop taking ECN bits into account in fib6-rules
fib: rules: remove duplicated nla policies
ipv6: fix memory leak in fib6_rule_suppress
ipv6: fib6: remove redundant initialization of variable err
fib: use indirect call wrappers in the most common fib_rules_ops
ipv6: fib6: avoid indirect calls from fib6_rule_lookup
net: fib_notifier: propagate extack down to the notifier block callback
ipv6: do not free rt if FIB_LOOKUP_NOREF is set on suppress rule
ipv6: honor RT6_LOOKUP_F_DST_NOREF in rule lookup logic
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 372
ipv6: Use result arg in fib_lookup_arg consistently
ipv6: fib6_rule_action_alt needs to return -EAGAIN
ipv6: Pass fib6_result to fib lookups
net/ipv6: Add fib6_lookup
net/ipv6: Refactor fib6_rule_action
net: fib_rules: add extack support
net: Drop pernet_operations::async
net/ipv6: Pass skb to route lookup
ipv6: route: dissect flow in input path if fib rules need it
ipv6: fib6_rules: support for match on sport, dport and ip proto
net: Convert fib6_rules_net_ops
net: ipv6: avoid overhead when no custom FIB rules are installed
ipv6: fib_rules: Dump rules during registration to FIB chain
ipv6: fib_rules: Check if rule is a default rule
ipv6: Do not leak throw route references
net: flow: Add l3mdev flow update
net: Add l3mdev rule
ipv6: fix the incorrect return value of throw route

Use imperative mood as other subjects do, tell the codebase what do do.



Wed, Feb 28, 2024 at 09:24:55AM CET, Lena.Wang@mediatek.com wrote:
>From bf53859b379a653eec8a14fbb3f29286f9f888fb Mon Sep 17 00:00:00 2001
>From: shiming cheng <shiming.cheng@mediatek.com>

Names start with capital letters.


>Date: Mon, 26 Feb 2024 20:17:58 +0800
>Subject: [PATCH net v2] Net:cache didn't flush when ipv6 rule changed

I don't understand why you put these "headers" here. Only one "from" is
enough in this case (you are submitting the patch in stead of another
person).

If you are not, I suggest to use git-send-email for submissions.


>
>When changed from old rule&route configure to new one as below,

"as below" where?

>ipv6 cache dst_entry did not change to new route table as no
>cache flush callback function, then forward to wrong out interface.

I don't understand this sentence :/


>When fib6_check dst_entry, the fib6_node version[fn_sernm] is
>always the same with socket dst_cookie, old cache dst_entry is
>always used and no chance to update.

Sorry, this is too cryptic for me to understand :/


>
>So we need to update fib6_node version when rule changed and
>flush cache to avoid dispatching a wrong interface.

Be imperative in the patch description too, tell the codebase what do do.

https://www.kernel.org/doc/html/v6.6/process/submitting-patches.html#describe-your-changes



>
>Signed-off-by: shiming cheng <shiming.cheng@mediatek.com>

Names start with capital letters.

Also, when you submit the patch, your signed-off-by tag should be here
as well.


>---
>v2: 
>    1. Add the fix tag.

And there, there is none...


pw-bot: cr


>    2. Changes according to David Ahern's suggestions, modify flush
>functions 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
>