[resend] [PATCH] IPv4: Reset scope when changing address

[resend] [PATCH] IPv4: Reset scope when changing address

[Bjørn Mork]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset=us-ascii, Size: 1687 bytes --]

<#part type=text/plain nofile=yes>
Any comments on this?  Apparently introduced in 2.1.68, so there's not
much hurry.  But I'd still like to hear whether that analysis is correct
or not...
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="==-=-="

The bug did bite at least one user, who did have to resort to rebooting
the system after an "ifconfig eth0 127.0.0.1" typo.  

Deleting the address and adding a new is a less intrusive workaround.
But I still beleive this is a bug that should be fixed.  Some way or
another.

Another possibility would be to remove the scope mangling based on
address.  This will always be incomplete (are 127/8 the only address
space with host scope requirements?)


Bjørn


<#part type=text/x-diff filename="devinet-rt_scope-fix.patch" disposition=inline nofile=yes>
We set the scope to RT_SCOPE_HOST if an IPv4 interface is configured
with a loopback address (127/8).  The scope is never reset, and will
remain set to RT_SCOPE_HOST after changing the address. This patch
resets the scope if the address is changed again, to restore normal
functionality.

Signed-off-by: Bjorn Mork <bjorn@mork.no>

--==-=-=

 devinet.c |    1 +
 1 file changed, 1 insertion(+)


--- linux-2.6.24-rc8.orig/net/ipv4/devinet.c	2008-01-16 05:22:48.000000000 +0100
+++ linux-2.6.24-rc8/net/ipv4/devinet.c	2008-01-23 19:17:30.000000000 +0100
@@ -753,6 +753,7 @@
 			inet_del_ifa(in_dev, ifap, 0);
 			ifa->ifa_broadcast = 0;
 			ifa->ifa_anycast = 0;
+			ifa->ifa_scope = 0;
 		}
 
 		ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;

--==-=-=
Content-Type: text/plain; charset=iso-8859-1



--==-=-=--

Re: [resend] [PATCH] IPv4: Reset scope when changing address

[David Miller]

From: Bjørn_Mork <bjorn@mork.no>
Date: Sat, 16 Feb 2008 12:45:31 +0100

> <#part type=text/plain nofile=yes>
> Any comments on this?  Apparently introduced in 2.1.68, so there's not
> much hurry.  But I'd still like to hear whether that analysis is correct
> or not...
> MIME-Version: 1.0
> Content-Type: multipart/mixed; boundary="==-=-="

Please clear up all of the inline mime tag stuff in your
outgoing emails.  Your description and patch is very difficult
to read because of this.

Thank you.

Re: [resend] [PATCH] IPv4: Reset scope when changing address

[Bjørn Mork]

David Miller <davem@davemloft.net> writes:

> Please clear up all of the inline mime tag stuff in your
> outgoing emails.  Your description and patch is very difficult
> to read because of this.

Ouch, sorry. I wish I could blame my user agent, but this was mostly my
sausage fingers..

New attempt:


This bug did bite at least one user, who did have to resort to rebooting
the system after an "ifconfig eth0 127.0.0.1" typo.  

Deleting the address and adding a new is a less intrusive workaround.
But I still beleive this is a bug that should be fixed.  Some way or
another.

Another possibility would be to remove the scope mangling based on
address.  This will always be incomplete (are 127/8 the only address
space with host scope requirements?)



We set the scope to RT_SCOPE_HOST if an IPv4 interface is configured
with a loopback address (127/8).  The scope is never reset, and will
remain set to RT_SCOPE_HOST after changing the address. This patch
resets the scope if the address is changed again, to restore normal
functionality.

Signed-off-by: Bjorn Mork <bjorn@mork.no>
---
 devinet.c |    1 +
 1 file changed, 1 insertion(+)


--- linux-2.6.24-rc8.orig/net/ipv4/devinet.c	2008-01-16 05:22:48.000000000 +0100
+++ linux-2.6.24-rc8/net/ipv4/devinet.c	2008-01-23 19:17:30.000000000 +0100
@@ -753,6 +753,7 @@
 			inet_del_ifa(in_dev, ifap, 0);
 			ifa->ifa_broadcast = 0;
 			ifa->ifa_anycast = 0;
+			ifa->ifa_scope = 0;
 		}
 
 		ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;

Re: [resend] [PATCH] IPv4: Reset scope when changing address

[David Miller]

From: Bjørn_Mork <bjorn@mork.no>
Date: Sun, 24 Feb 2008 19:12:38 +0100

> We set the scope to RT_SCOPE_HOST if an IPv4 interface is configured
> with a loopback address (127/8).  The scope is never reset, and will
> remain set to RT_SCOPE_HOST after changing the address. This patch
> resets the scope if the address is changed again, to restore normal
> functionality.
> 
> Signed-off-by: Bjorn Mork <bjorn@mork.no>

This patch looks fine, applied, thanks!