Today a guest is free to access as many nodes in a single transaction
as it wants. This can lead to unbounded memory consumption in Xenstore
as there is the need to keep track of all nodes having been accessed
during a transaction.
In oxenstored the number of requests in a transaction is being limited
via a quota maxrequests (default is 1024). As multiple accesses of a
node are not problematic in C Xenstore, limit the number of accessed
nodes.
In order to let read_node() detect a quota error in case too many nodes
are being accessed, check the return value of access_node() and return
NULL in case an error has been seen. Introduce __must_check and add it
to the access_node() prototype.
This is part of XSA-326 / CVE-2022-42314.
Suggested-by: Julien Grall <julien@xen.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
(cherry picked from commit 268369d8e3)
Today there are multiple copies of the ROUNDUP() macro in various
sources and headers. Define it once in tools/include/xen-tools/libs.h.
Using xen-tools/libs.h enables removing copies of MIN() and MAX(), too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
... rather than implementing them separately for libxc and libxl. They will
shortly be wanted in libx86 as well.
Fix up the style/consistency in the declaration, but no functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Both Xen and the toolstack have need of the same logic when it comes to
manipulation and checking of the CPUID and MSR values offered to guests. To
that end, libx86 is being introduced to allow Xen and the toolstack to share a
single implementation, rather than duplicating the logic.
No functional change.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
xen-tools/libs.h currently contains a shared BUILD_BUG_ON() implementation and
is used by some tools. Extend this to include ARRAY_SIZE and clean up all the
opencoding.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
3a7f872a ("tools: lift BUILD_BUG_ON to a tools header file") was taken
out from an rather old half finished branch by dropping unrelated
changes. Unfortunately two issues sneaked in.
1. Hvmloader should be standalone. Revert the changes to hvmloader.
2. The define guard in libs.h was erroneously deleted. Add that back.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Only define BUILD_BUG_ON when there isn't one already, because mini-os
currently leaks that.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Juergen Gross
Andrew Cooper
Roger Pau Monné
Wei Liu