netdev: avoid skipping objects on race with device disappearance

If the currently dumped device disappears while we were mid-dump
we will get the next device without resetting the sub-object ID.
This is quite unlikely, it was reported by an AI tool not a real
user. Let's fix it for better dump consistency.

We only intend to cover the case where device A disappears
and we skip over sub-objects of device B which was stable (B existed
before and after the dump). We don't intend to provide stable
results for any device that gets created or deleted during
the dump.

Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260903221154.3359889-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jakub Kicinski 2026-09-03 15:11:54 -07:00
commit 761ae184f8
2 changed files with 23 additions and 7 deletions