59d3efd27c
The commits referenced below allows userspace to use the NLM_F_ECHO flag for RTM_NEW/DELLINK operations to receive unicast notifications for the affected link. Prior to these changes, applications may have relied on multicast notifications to learn the same information without specifying the NLM_F_ECHO flag. For such applications, the mentioned commits changed the behavior for requests not using NLM_F_ECHO. Multicast notifications are still received, but now use the portid of the requester and the sequence number of the request instead of zero values used previously. For the application, this message may be unexpected and likely handled as a response to the NLM_F_ACKed request, especially if it uses the same socket to handle requests and notifications. To fix existing applications relying on the old notification behavior, set the portid and sequence number in the notification only if the request included the NLM_F_ECHO flag. This restores the old behavior for applications not using it, but allows unicasted notifications for others. Fixes:f3a63cce1b("rtnetlink: Honour NLM_F_ECHO flag in rtnl_delete_link") Fixes:d88e136cab("rtnetlink: Honour NLM_F_ECHO flag in rtnl_newlink_create") Signed-off-by: Martin Willi <martin@strongswan.org> Acked-by: Guillaume Nault <gnault@redhat.com> Acked-by: Hangbin Liu <liuhangbin@gmail.com> Link: https://lore.kernel.org/r/20230411074319.24133-1-martin@strongswan.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.