[PATCH] ipv6: socket SO_BINDTODEVICE lookup routing fail without IPv6 rule.

[David Ahern]

On 1/2/25 2:51 AM, shiming cheng wrote:
>      When using socket IPv6 with SO_BINDTODEVICE, if IPv6 rule is not
>         matched, it will return ENETUNREACH. In fact, IPv4 does not behave
>         this way. IPv4 prioritizes looking up IP rules for routing and
>         forwarding, if not matched it will use socket-bound out interface
>         to send packets. The modification here is to make IPv6 behave the
>         same as IPv4. If IP rule is not found, it will also use
>         socket-bound out interface to send packts.
> 

Please create test cases for IPv4 and IPv6 showing the problem - what
you are configuring and the expected result.

Also, commit messages should align with first column unless there is a
reason for an indentation.