forked from Minki/linux
9996bd4947
'xenbus_backend' watches 'state' of devices, which is writable by guests. Hence, if guests intensively updates it, dom0 will have lots of pending events that exhausting memory of dom0. In other words, guests can trigger dom0 memory pressure. This is known as XSA-349. However, the watch callback of it, 'frontend_changed()', reads only 'state', so doesn't need to have the pending events. To avoid the problem, this commit disallows pending watch messages for 'xenbus_backend' using the 'will_handle()' watch callback. This is part of XSA-349 Cc: stable@vger.kernel.org Signed-off-by: SeongJae Park <sjpark@amazon.de> Reported-by: Michael Kurth <mku@amazon.de> Reported-by: Pawel Wieczorkiewicz <wipawel@amazon.de> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> |
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| .. | ||
| Makefile | ||
| xenbus_client.c | ||
| xenbus_comms.c | ||
| xenbus_dev_backend.c | ||
| xenbus_dev_frontend.c | ||
| xenbus_probe_backend.c | ||
| xenbus_probe_frontend.c | ||
| xenbus_probe.c | ||
| xenbus_xs.c | ||
| xenbus.h | ||