[pxe] Discard queued PXE UDP packets when under memory pressure

The PXE UDP receive queue may grow without limit if the PXE NBP does
not call PXENV_UDP_READ sufficiently frequently.

Fix by implementing a cache discarder for received PXE UDP packets
(similar to the TCP cache discarder).

Reported-by: Tal Shorer <shorer@amazon.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
1 file changed
tree: 8cb6669eeaa05c9233f1932fe2c40f9ec7c3f857
  1. .github/
  2. contrib/
  3. src/
  4. COPYING
  5. COPYING.GPLv2
  6. COPYING.UBDL
  7. README