Re: [PATCH v2] udp: correct source address for ICMP messages

[Stefano Brivio <sbrivio@redhat.com>]

On Wed, 26 Mar 2025 11:59:02 -0400
Jon Maloy <jmaloy@redhat.com> wrote:

> While developing traceroute forwarding tap-to-sock we found that
> struct msghdr.msg_name for the ICMPs in the opposite direction always
> contains the destination address of the original UDP message, and not,
> as one might expect, the one of the host which created the error message.
> 
> Study of the kernel code reveals that this address instead is appended
> as extra data after the received struct sock_extended_err area.
> 
> We now change the ICMP receive code accordingly.
> 
> Fixes: 55431f0077b6 ("udp: create and send ICMPv4 to local peer when applicable")
> Fixes: 68b04182e07d ("udp: create and send ICMPv6 to local peer when applicable")
> 
> Signed-off-by: Jon Maloy <jmaloy@redhat.com>
> ---
> v2: Removed stray comment and unecessary initializations, as per
>     feedback from David Gibson

Applied.

-- 
Stefano