[PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Mike Manning]

commit f1705ec197e7 ("net: ipv6: Make address flushing on ifdown 
optional") added the option to retain user configured addresses on an
admin down. A comment to one of the later revisions suggested using
the IFA_F_PERMANENT flag rather than adding a user_managed boolean to
the ifaddr struct. A side effect of this change is that link local and
loopback addresses were also retained which was not part of the
objective of the original changes. The commit 70af921db6f8 ("net: ipv6: 
Do not keep linklocal and loopback addresses") ensures that these are
no longer kept. Similarly, the present fix ensures that these addresses
are not incorrectly fixed up. 

Testing also with the recent patch in place to delete host routes on
ifdown still shows that fixup of the LL & loopback addrs is incorrectly
being attempted (and without that patch was causing a crash in fib6).
Another approach to this is through code inspection by checking where
the user_managed flag in the original dahern patch (which we have been
using for nearly a year) has been replaced by checking IFA_F_PERMANENT.

Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@brocade.com>
---
 net/ipv6/addrconf.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 23cec53..cba4e10 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3200,6 +3200,12 @@ static void l3mdev_check_host_rt(struct inet6_dev *idev,
 }
 #endif
 
+static bool addr_is_local(const struct in6_addr *addr)
+{
+	return ipv6_addr_type(addr) &
+		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
+}
+
 static int fixup_permanent_addr(struct inet6_dev *idev,
 				struct inet6_ifaddr *ifp)
 {
@@ -3238,6 +3244,7 @@ static void addrconf_permanent_addr(struct net_device *dev)
 
 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
 		if ((ifp->flags & IFA_F_PERMANENT) &&
+		    !addr_is_local(&ifp->addr) &&
 		    fixup_permanent_addr(idev, ifp) < 0) {
 			write_unlock_bh(&idev->lock);
 			ipv6_del_addr(ifp);
@@ -3448,12 +3455,6 @@ static void addrconf_type_change(struct net_device *dev, unsigned long event)
 		ipv6_mc_unmap(idev);
 }
 
-static bool addr_is_local(const struct in6_addr *addr)
-{
-	return ipv6_addr_type(addr) &
-		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
-}
-
 static int addrconf_ifdown(struct net_device *dev, int how)
 {
 	struct net *net = dev_net(dev);
-- 
1.7.10.4

Re: [PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[David Ahern]

On 4/22/16 10:14 AM, Mike Manning wrote:
> commit f1705ec197e7 ("net: ipv6: Make address flushing on ifdown
> optional") added the option to retain user configured addresses on an
> admin down. A comment to one of the later revisions suggested using
> the IFA_F_PERMANENT flag rather than adding a user_managed boolean to
> the ifaddr struct. A side effect of this change is that link local and
> loopback addresses were also retained which was not part of the
> objective of the original changes. The commit 70af921db6f8 ("net: ipv6:
> Do not keep linklocal and loopback addresses") ensures that these are
> no longer kept. Similarly, the present fix ensures that these addresses
> are not incorrectly fixed up.
>
> Testing also with the recent patch in place to delete host routes on
> ifdown still shows that fixup of the LL & loopback addrs is incorrectly
> being attempted (and without that patch was causing a crash in fib6).
> Another approach to this is through code inspection by checking where
> the user_managed flag in the original dahern patch (which we have been
> using for nearly a year) has been replaced by checking IFA_F_PERMANENT.
>
> Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
> Signed-off-by: Mike Manning <mmanning@brocade.com>
> ---
>   net/ipv6/addrconf.c |   13 +++++++------
>   1 file changed, 7 insertions(+), 6 deletions(-)
>

Acked-by: David Ahern <dsa@cumulusnetworks.com>

[PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Mike Manning]

f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional") added
the option to retain user configured addresses on an admin down. A comment
to one of the later revisions suggested using the IFA_F_PERMANENT flag rather
than adding a user_managed boolean to the ifaddr struct. A side effect of
this change is that link local and loopback addresses were also retained which
was not part of the objective of the original changes. The fix 70af921db6f8
("net: ipv6: Do not keep linklocal and loopback addresses") ensures that these
are no longer kept. Similarly, the present fix ensures that these addresses
are not fixed up, otherwise the incorrect fixup triggers a crash in fib6.

Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@brocade.com>
---
 net/ipv6/addrconf.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 23cec53..cba4e10 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3200,6 +3200,12 @@ static void l3mdev_check_host_rt(struct inet6_dev *idev,
 }
 #endif
 
+static bool addr_is_local(const struct in6_addr *addr)
+{
+	return ipv6_addr_type(addr) &
+		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
+}
+
 static int fixup_permanent_addr(struct inet6_dev *idev,
 				struct inet6_ifaddr *ifp)
 {
@@ -3238,6 +3244,7 @@ static void addrconf_permanent_addr(struct net_device *dev)
 
 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
 		if ((ifp->flags & IFA_F_PERMANENT) &&
+		    !addr_is_local(&ifp->addr) &&
 		    fixup_permanent_addr(idev, ifp) < 0) {
 			write_unlock_bh(&idev->lock);
 			ipv6_del_addr(ifp);
@@ -3448,12 +3455,6 @@ static void addrconf_type_change(struct net_device *dev, unsigned long event)
 		ipv6_mc_unmap(idev);
 }
 
-static bool addr_is_local(const struct in6_addr *addr)
-{
-	return ipv6_addr_type(addr) &
-		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
-}
-
 static int addrconf_ifdown(struct net_device *dev, int how)
 {
 	struct net *net = dev_net(dev);
-- 
1.7.10.4

Re: [PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Sergei Shtylyov]

Hello.

On 4/18/2016 5:23 PM, Mike Manning wrote:

> f1705ec197e7 "Make address flushing on ifdown optional" added the option

    Looking further, this doesn't seem like a complete commit summary. And you 
need to enclose it in parens too.

> to retain user configured addresses on an admin down. A comment to one of
> the later revisions suggested using the IFA_F_PERMANENT flag rather than
> adding a user_managed boolean to the ifaddr struct. A side effect of this
> change is that link local and loopback addresses were also retained which
> was not part of the objective of the original changes. The fix 70af921db6f8
> "Do not keep linklocal and loopback addresses" ensures that these are no

    Again, () are needed around the summary.

> longer kept. Similarly, the present fix ensures that these addresses are not
> fixed up either, otherwise the incorrect fixup triggers a crash in fib6.
>
> Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
> Signed-off-by: Mike Manning <mmanning@brocade.com>
[...]

MBR, Sergei

Re: [PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Mike Manning]

On 04/18/2016 03:39 PM, David Ahern wrote:
> On 4/18/16 8:23 AM, Mike Manning wrote:
>> f1705ec197e7 "Make address flushing on ifdown optional" added the option
>> to retain user configured addresses on an admin down. A comment to one of
>> the later revisions suggested using the IFA_F_PERMANENT flag rather than
>> adding a user_managed boolean to the ifaddr struct. A side effect of this
>> change is that link local and loopback addresses were also retained which
>> was not part of the objective of the original changes. The fix 70af921db6f8
>> "Do not keep linklocal and loopback addresses" ensures that these are no
>> longer kept. Similarly, the present fix ensures that these addresses are not
>> fixed up either, otherwise the incorrect fixup triggers a crash in fib6.
>>
>> Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
>> Signed-off-by: Mike Manning <mmanning@brocade.com>
>> ---
>>   net/ipv6/addrconf.c |   13 +++++++------
>>   1 file changed, 7 insertions(+), 6 deletions(-)
> 
> Is this a v2? Code change is the same.

This is the same changeset, but Sergei requested on Saturday to change the wording as follows:


    scripts/checkpatch.pl now enforces commit citing certain style: <12-digit 

SHA1> ("<comit summary>").



> 
> Acked-by: David Ahern <dsa@cumulusnetworks.com>

Re: [PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[David Ahern]

On 4/18/16 8:23 AM, Mike Manning wrote:
> f1705ec197e7 "Make address flushing on ifdown optional" added the option
> to retain user configured addresses on an admin down. A comment to one of
> the later revisions suggested using the IFA_F_PERMANENT flag rather than
> adding a user_managed boolean to the ifaddr struct. A side effect of this
> change is that link local and loopback addresses were also retained which
> was not part of the objective of the original changes. The fix 70af921db6f8
> "Do not keep linklocal and loopback addresses" ensures that these are no
> longer kept. Similarly, the present fix ensures that these addresses are not
> fixed up either, otherwise the incorrect fixup triggers a crash in fib6.
>
> Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
> Signed-off-by: Mike Manning <mmanning@brocade.com>
> ---
>   net/ipv6/addrconf.c |   13 +++++++------
>   1 file changed, 7 insertions(+), 6 deletions(-)

Is this a v2? Code change is the same.

Acked-by: David Ahern <dsa@cumulusnetworks.com>

[PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Mike Manning]

f1705ec197e7 "Make address flushing on ifdown optional" added the option
to retain user configured addresses on an admin down. A comment to one of
the later revisions suggested using the IFA_F_PERMANENT flag rather than
adding a user_managed boolean to the ifaddr struct. A side effect of this
change is that link local and loopback addresses were also retained which
was not part of the objective of the original changes. The fix 70af921db6f8
"Do not keep linklocal and loopback addresses" ensures that these are no
longer kept. Similarly, the present fix ensures that these addresses are not
fixed up either, otherwise the incorrect fixup triggers a crash in fib6.

Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@brocade.com>
---
 net/ipv6/addrconf.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 23cec53..cba4e10 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3200,6 +3200,12 @@ static void l3mdev_check_host_rt(struct inet6_dev *idev,
 }
 #endif
 
+static bool addr_is_local(const struct in6_addr *addr)
+{
+	return ipv6_addr_type(addr) &
+		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
+}
+
 static int fixup_permanent_addr(struct inet6_dev *idev,
 				struct inet6_ifaddr *ifp)
 {
@@ -3238,6 +3244,7 @@ static void addrconf_permanent_addr(struct net_device *dev)
 
 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
 		if ((ifp->flags & IFA_F_PERMANENT) &&
+		    !addr_is_local(&ifp->addr) &&
 		    fixup_permanent_addr(idev, ifp) < 0) {
 			write_unlock_bh(&idev->lock);
 			ipv6_del_addr(ifp);
@@ -3448,12 +3455,6 @@ static void addrconf_type_change(struct net_device *dev, unsigned long event)
 		ipv6_mc_unmap(idev);
 }
 
-static bool addr_is_local(const struct in6_addr *addr)
-{
-	return ipv6_addr_type(addr) &
-		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
-}
-
 static int addrconf_ifdown(struct net_device *dev, int how)
 {
 	struct net *net = dev_net(dev);
-- 
1.7.10.4

Re: [PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Mike Manning]

On 04/16/2016 07:26 PM, David Ahern wrote:
> On 4/15/16 9:13 PM, Mike Manning wrote:
>> f1705ec197e7 added the option to retain user configured addresses on an
>> admin down. A comment to one of the later revisions suggested using the
>> IFA_F_PERMANENT flag rather than adding a user_managed boolean to the
>> ifaddr struct. A side effect of this change is that link local and
>> loopback addresses are also retained which is not part of the objective
>> of f1705ec197e7. Add check so that these addresses are not fixed up,
>> given that a related fix 70af921db6f8 ensures that they are not kept in
>> the first place, otherwise this incorrect fixup triggers a crash in fib6.
> 
> oops in fib6_del?
>
 
[  285.734883]  [<ffffffff8125ad15>] ? dump_stack+0x5c/0x77
[  285.734887]  [<ffffffff8105d907>] ? warn_slowpath_common+0x77/0xb0
[  285.734889]  [<ffffffff814f3e40>] ? fib6_clean_tohost+0x50/0x50
[  285.734891]  [<ffffffff814fbe3e>] ? fib6_del+0x22e/0x290
[  285.734893]  [<ffffffff814fbf22>] ? fib6_clean_node+0x82/0x120
[  285.734895]  [<ffffffff814f9a0d>] ? fib6_walk_continue+0x16d/0x1a0
[  285.734897]  [<ffffffff814f9ad4>] ? fib6_walk+0x54/0x80
[  285.734899]  [<ffffffff814f9b42>] ? fib6_clean_tree+0x42/0x50
[  285.734901]  [<ffffffff814fbea0>] ? fib6_del+0x290/0x290
[  285.734902]  [<ffffffff814f3e40>] ? fib6_clean_tohost+0x50/0x50
[  285.734904]  [<ffffffff814f9ba8>] ? __fib6_clean_all+0x58/0x90
[  285.734906]  [<ffffffff814f9326>] ? rt6_ifdown+0x36/0x1e0
[  285.734908]  [<ffffffff814fbf0f>] ? fib6_clean_node+0x6f/0x120
[  285.734911]  [<ffffffff814eeb6b>] ? addrconf_ifdown+0x3b/0x580
[  285.734913]  [<ffffffff814f9b42>] ? fib6_clean_tree+0x42/0x50
[  285.734914]  [<ffffffff814f1ea0>] ? addrconf_notify+0xf0/0xb10
[  285.734916]  [<ffffffff814f9bb0>] ? __fib6_clean_all+0x60/0x90

>> Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
>> Signed-off-by: Mike Manning <mmanning@brocade.com>
>> ---
> 
> for the change
> Acked-by: David Ahern <dsa@cumulusnetworks.com>
> 

Re: [PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[David Ahern]

On 4/15/16 9:13 PM, Mike Manning wrote:
> f1705ec197e7 added the option to retain user configured addresses on an
> admin down. A comment to one of the later revisions suggested using the
> IFA_F_PERMANENT flag rather than adding a user_managed boolean to the
> ifaddr struct. A side effect of this change is that link local and
> loopback addresses are also retained which is not part of the objective
> of f1705ec197e7. Add check so that these addresses are not fixed up,
> given that a related fix 70af921db6f8 ensures that they are not kept in
> the first place, otherwise this incorrect fixup triggers a crash in fib6.

oops in fib6_del?

>
> Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
> Signed-off-by: Mike Manning <mmanning@brocade.com>
> ---

for the change
Acked-by: David Ahern <dsa@cumulusnetworks.com>

Re: [PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Sergei Shtylyov]

Hello.

On 4/16/2016 6:13 AM, Mike Manning wrote:

> f1705ec197e7 added the option to retain user configured addresses on an
> admin down. A comment to one of the later revisions suggested using the
> IFA_F_PERMANENT flag rather than adding a user_managed boolean to the
> ifaddr struct. A side effect of this change is that link local and
> loopback addresses are also retained which is not part of the objective
> of f1705ec197e7. Add check so that these addresses are not fixed up,
> given that a related fix 70af921db6f8 ensures that they are not kept in

    scripts/checkpatch.pl now enforces commit citing certain style: <12-digit 
SHA1> ("<comit summary>").

> the first place, otherwise this incorrect fixup triggers a crash in fib6.
>
> Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
> Signed-off-by: Mike Manning <mmanning@brocade.com>
[...]

MBR, Sergei

[PATCH] net: ipv6: Do not fix up linklocal and loopback addresses

[Mike Manning]

f1705ec197e7 added the option to retain user configured addresses on an
admin down. A comment to one of the later revisions suggested using the
IFA_F_PERMANENT flag rather than adding a user_managed boolean to the
ifaddr struct. A side effect of this change is that link local and
loopback addresses are also retained which is not part of the objective
of f1705ec197e7. Add check so that these addresses are not fixed up,
given that a related fix 70af921db6f8 ensures that they are not kept in
the first place, otherwise this incorrect fixup triggers a crash in fib6.

Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@brocade.com>
---
 net/ipv6/addrconf.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 23cec53..cba4e10 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3200,6 +3200,12 @@ static void l3mdev_check_host_rt(struct inet6_dev *idev,
 }
 #endif
 
+static bool addr_is_local(const struct in6_addr *addr)
+{
+	return ipv6_addr_type(addr) &
+		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
+}
+
 static int fixup_permanent_addr(struct inet6_dev *idev,
 				struct inet6_ifaddr *ifp)
 {
@@ -3238,6 +3244,7 @@ static void addrconf_permanent_addr(struct net_device *dev)
 
 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
 		if ((ifp->flags & IFA_F_PERMANENT) &&
+		    !addr_is_local(&ifp->addr) &&
 		    fixup_permanent_addr(idev, ifp) < 0) {
 			write_unlock_bh(&idev->lock);
 			ipv6_del_addr(ifp);
@@ -3448,12 +3455,6 @@ static void addrconf_type_change(struct net_device *dev, unsigned long event)
 		ipv6_mc_unmap(idev);
 }
 
-static bool addr_is_local(const struct in6_addr *addr)
-{
-	return ipv6_addr_type(addr) &
-		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
-}
-
 static int addrconf_ifdown(struct net_device *dev, int how)
 {
 	struct net *net = dev_net(dev);
-- 
1.7.10.4