Merge branch 'vsock-some-fixes-due-to-transport-de-assignment'

Stefano Garzarella says:

====================
vsock: some fixes due to transport de-assignment

v1: https://lore.kernel.org/netdev/20250108180617.154053-1-sgarzare@redhat.com/
v2:
- Added patch 3 to cancel the virtio close delayed work when de-assigning
  the transport
- Added patch 4 to clean the socket state after de-assigning the transport
- Added patch 5 as suggested by Michael and Hyunwoo Kim. It's based on
  Hyunwoo Kim and Wongi Lee patch [1] but using WARN_ON and covering more
  functions
- Added R-b/T-b tags

This series includes two patches discussed in the thread started by
Hyunwoo Kim a few weeks ago [1], plus 3 more patches added after some
discussions on v1 (see changelog). All related to the case where a vsock
socket is de-assigned from a transport (e.g., because the connect fails
or is interrupted by a signal) and then assigned to another transport
or to no-one (NULL).

I tested with usual vsock test suite, plus Michal repro [2]. (Note: the repo
works only if a G2H transport is not loaded, e.g. virtio-vsock driver).

The first patch is a fix more appropriate to the problem reported in
that thread, the second patch on the other hand is a related fix but
of a different problem highlighted by Michal Luczaj. It's present only
in vsock_bpf and already handled in af_vsock.c
The third patch is to cancel the virtio close delayed work when de-assigning
the transport, the fourth patch is to clean the socket state after de-assigning
the transport, the last patch adds warnings and prevents null-ptr-deref in
vsock_*[has_data|has_space].

Hyunwoo Kim, Michal, if you can test and report your Tested-by that
would be great!

[1] https://lore.kernel.org/netdev/Z2K%2FI4nlHdfMRTZC@v4bel-B760M-AORUS-ELITE-AX/
[2] https://lore.kernel.org/netdev/2b3062e3-bdaa-4c94-a3c0-2930595b9670@rbox.co/
====================

Link: https://patch.msgid.link/20250110083511.30419-1-sgarzare@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>