lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Fri, 20 Apr 2012 21:25:33 -0300
From:	Flavio Leitner <>
To:	netdev <>
Cc:	Herbert Xu <>
Subject: restoring IP multicast addresses when restarting the interface.

Hello folks,

I was told that ntp in multicast mode was not working if you
restart the interface (ifdown <iface> ; ifup <iface) on an
older kernel.

It seemed obvious to me, but when I tried to reproduce this
upstream (last kernel of today), I noticed that the kernel
does restore the previous added multicast addresses. Therefore,
there is no issues.

I found that this is due to mainly this commit below which
doesn't remove idev when the addresses are deleted.

commit 6363097cc4d182f93788131b5d8f72aa91d950a0
Author: Herbert Xu <>
Date:   Thu Jun 7 18:35:38 2007 -0700

    [IPV4]: Do not remove idev when addresses are cleared
    Now that we create idev before addresses are added, it no longer makes
    sense to remove them when addresses are all deleted.
    Signed-off-by: Herbert Xu <>
    Signed-off-by: David S. Miller <>

Although the new behavior seems nice and save some user space
work, I think it was unintentional and likely to be a bug.

What you guys think?

To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to
More majordomo info at

Powered by blists - more mailing lists