On 8/16/24 8:45 AM, Martin Kletzander wrote:
Somehow it happened that some kernels (I noticed this with 6.10.0 and 6.10.2 on
various machines) started sending NLMSG_DONE message (as they probably should've
even before),
This comment shows the kernel commit that caused it:
https://bugzilla.redhat.com/2302245#c4
This bug also points out that we're only reading a single response
message, which could theoretically lead to missing the tail of a very
long arp table. But that's another battle for another day.
but our check for it could've never worked and now `virsh
domifaddr --source arp` sometimes fails with "wrong nlmsg len". So I set out on
a quest to tame the netlink beast and though fierceful debugging and... Oh, I
forgot, nobody reads cover letters. Never mind.
Oh come on!!! Just when it was getting interesting! Where is the gyring
and gimbling in the wabe?? The mome raths?? The mimsy borogroves????
(in case that makes no sense:
https://www.poetryfoundation.org/poems/42916/jabberwocky - my 3rd or 4th
favorite poem, after 2 or 3 by Dr. Seuss)
Martin Kletzander (3):
virarptable: Properly calculate rtattr length
virarptable: Fix check for message length
virarptable: End parsing earlier in case of NLMSG_DONE
src/util/virarptable.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)