linux/include/xen
Juergen Gross fe415186b4 xen/console: harden hvc_xen against event channel storms
The Xen console driver is still vulnerable for an attack via excessive
number of events sent by the backend. Fix that by using a lateeoi event
channel.

For the normal domU initial console this requires the introduction of
bind_evtchn_to_irq_lateeoi() as there is no xenbus device available
at the time the event channel is bound to the irq.

As the decision whether an interrupt was spurious or not requires to
test for bytes having been read from the backend, move sending the
event into the if statement, as sending an event without having found
any bytes to be read is making no sense at all.

This is part of XSA-391

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
V2:
- slightly adapt spurious irq detection (Jan Beulich)
V3:
- fix spurious irq detection (Jan Beulich)
2021-12-16 08:24:08 +01:00
..
arm xen: allow pv-only hypercalls only with CONFIG_XEN_PV 2021-11-02 08:11:01 -05:00
interface xen: fix wrong SPDX headers of Xen related headers 2021-11-02 07:45:44 -05:00
acpi.h xen: Remove support for PV ACPI cpu/memory hotplug 2021-04-23 09:31:50 +02:00
balloon.h xen/balloon: rename alloc/free_xenballooned_pages 2021-11-04 12:59:44 -05:00
events.h xen/console: harden hvc_xen against event channel storms 2021-12-16 08:24:08 +01:00
features.h
grant_table.h Xen/gnttab: introduce common INVALID_GRANT_{HANDLE,REF} 2021-03-10 16:39:29 -06:00
hvc-console.h
hvm.h xen: Move xen_setup_callback_vector() definition to include/xen/hvm.h 2020-06-11 15:15:19 +02:00
mem-reservation.h xen/balloon: add runtime control for scrubbing ballooned out pages 2018-09-14 08:51:10 -04:00
page.h swiotlb-xen: remove XEN_PFN_PHYS 2020-08-04 07:50:43 +02:00
pci.h xen-pciback: allow compiling on other archs than x86 2021-11-02 08:03:43 -05:00
platform_pci.h
swiotlb-xen.h Merge branch 'stable/for-linus-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb 2021-05-04 10:58:49 -07:00
xen-front-pgdir-shbuf.h xen: Introduce shared buffer helpers for page directory... 2018-12-18 12:15:55 -05:00
xen-ops.h xen/privcmd: drop "pages" parameter from xen_remap_pfn() 2021-10-05 08:20:27 +02:00
xen.h xen/balloon: rename alloc/free_xenballooned_pages 2021-11-04 12:59:44 -05:00
xenbus_dev.h
xenbus.h xen: add "not_essential" flag to struct xenbus_driver 2021-11-23 13:41:29 -06:00