Due to a typo the state record for a watch specifying a depth is
written only partially. Instead of using the correct length of the
xs_state_watch_ext structure only the length of the xs_state_watch
structure was used when writing the data.
Fix that by using the correct length.
This is XSA-514 / CVE-2026-79607
Fixes: db98de120c ("tools/xenstored: add depth information to watches")
Reported-by: Andrii Sultanov <andriy.sultanov@vates.tech>
Signed-off-by: Juergen Gross <jgross@suse.com>
With unprivileged domains now capable to use the @releaseDomain watch,
there is no reason not to remove any node permissions which relate to
a domain which has been removed.
This resolves a complex scenario where a new domain could inherit the
permissions of an old one with the same domid.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Currently the @releaseDomain watch is allowed for dom0 only. This is
problematic for guests which want to give other domains access to
Xenstore entries, as they have no simple way to tell when such a
domain is stopped.
Allow @releaseDomain to be usable by all domains as the default.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Add support for using DOMID_ANY in node permissions to indicate that
all domains are allowed to access the node.
Add a new feature bit for indicating the support of DOMID_ANY.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
conn_delete_all_transactions() should be callable in any context,
resetting ALL transaction related data.
This includes number of active transactions and the transaction
pointer in struct connection.
So reset conn->trans to NULL in conn_delete_all_transactions() and
do the cleanup for each transaction in destroy_transaction().
This avoids triggering the assert() in conn_delete_all_transactions()
in case e.g. ignore_connection() was called while an operation inside
a transaction was performed, or XS_RESET_WATCHES was called in a
transaction.
This is XSA-484 / CVE-2026-23557.
Reported-by: Andrii Sultanov <andriy.sultanov@vates.tech>
Fixes: 1f9d04fb02 ("xenstored: allow guest to shutdown all its watches/transactions")
Signed-off-by: Juergen Gross <jgross@suse.com>
create_node() is called only for issued xenstore commands. This means
that the "conn" parameter is never NULL.
Remove checking whether "conn" is not NULL.
Coverity ID: 1690859
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Add XENSTORE_SERVER_FEATURE_WATCHDEPTH to the available features now
that all needed support has been added.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
With XENSTORE_SERVER_FEATURE_WATCHDEPTH available, special watch
handling needs to be extended:
- when a special watch is set with depth = 1, the domid is added to
the watch event
- it is possible to watch for @releaseDomain/<domid>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Today fire_watches() has the boolean "exact" parameter specifying how
the matching of the modified node with registered watches is to be
handled (only the exact node name is matching or all nodes being
in the subtree beneath the watched node).
For the handling of <special-watch>/<domid> watch events 2 additional
matching possibility needs to be added, as those events should only
be delivered to clients having requested such events, either by
watching <special-watch> with the depth=1 parameter, or by directly
watching for <special-watch>/<domid>, while the traditional special
watch events should NOT delivered to those watchers.
For this purpose rename the "exact" parameter to "match" and make it
an enum with four possible values.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
In case XENSTORE_SERVER_FEATURE_WATCHDEPTH is set, allow XS_WATCH to
have "depth" as 3rd parameter.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Add the depth for matching subdirectories of a watch to the watch
handling. A depth value of -1 is used for the current model of no
limit.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Expand the XS_GET_FEATURE command to allow an unprivileged domain to
read its own available features. While this information is available
via the related field in the shared page used for communication with
Xenstore, user land components of the domU would need special support
in the related kernel driver to obtain that data. With supporting the
XS_GET_FEATURE for that purpose, only an up to date libxenstore is
needed.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Add the implementation of the GET_QUOTA and SET_QUOTA wire commands.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Initialize the per-domain quota values with the global ones at domain
introduction. Use the per-domain quota settings when checking for
current values to exceed the quota.
Add per-domain quota support to live update.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Prepare using per-domain quota by splitting the acc[] array in struct
domain into an array with the current accounting data, and an array
of type struct quota for the per-domain quota and the seen max value
of the domain.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Communicate the global quota settings via the GLOBAL_QUOTA_DATA
record to the new Xenstore instance.
This avoids to lose global quota settings done via xenstore-control.
In theory it would be possible to drop any quota related command line
parameters in the live update case, but they don't do any harm, as
the record data is applied on top of the command line data.
For soft-quota just prepend "soft-" to the quota name.
Use sub-functions for building and analyzing the quota part of the
migration stream, as they will be reused for per-domain quotas.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Instead of having one array for hard quotas and one for soft quotas,
split them differently: have one array with the quota names and
descriptions, and one with the quota values (soft and hard) and the
maximum value so far.
This is in preparation of supporting per-domain quotas, as the layout
of the second array elements will be reused in the domain data.
While at it add an accessor for getting a soft quota value, as this
will be needed for per-domain quotas, too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Add central functions for checking a value (either an absolute one or
the current domain value plus an offset) against a specific quota.
This is in preparation of introducing per-domain quota.
The required changes allow to drop the "update" parameter from
domain_nbentry_fix().
While at it, make the returned error for exceeded quota consistent by
changing one instance from "E2BIG" to "ENOSPC".
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Today a domid passed in by a command is parsed using atoi(). This
will still "succeed" even with a domid like "x", resulting in "0" to
be used instead.
Use a common domid parser instead rejecting everything but integers
in the range 0..65535 like specified in docs/misc/xenstore.txt.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
The setting of errno in canonicalize() is rather fragile and seems to
be even wrong in one corner case: when the invalid path "/local/domain/"
is passed, sscanf() will set errno to 0, resulting in canonicalize() to
return NULL with errno being 0. This can result in triggering the
assert(conn->in == NULL) in consider_message().
Don't assume the initial setting of errno to "EINVAL" will stay valid
in all cases and set it to EINVAL only when returning NULL due to an
invalid path.
This is XSA-481/CVE-2026-23555
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <julien@xen.org>
Commit e5b0a94055 ("tools/xenstored: Auto-introduce domains") broke
xenstored live update, as init_domains() will be skipped when live
update is detected to have happened. This will leave priv_domid and
store_domid set as invalid.
Fix that by calling init_domains() in live update case, too. In case
of live update skip introducing any found domains, as this will be done
when reading the live update state.
Fixes: e5b0a94055 ("tools/xenstored: Auto-introduce domains")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
On a system without a control domain, a hardware|xenstore domain
starting xenstored shows:
common/grant_table.c:1041:d2v0 Could not find domain 32756
gnttab: error: mmap failed: Invalid argument
Could not initialize dom32756
setup_structure() does not get called without priv_domid. Subsequent
introduce_domain() calls will fault when calling fire_special_watches().
Default priv_domid to store_domid when there is no control domain.
Fixes: e5b0a94055 ("tools/xenstored: Auto-introduce domains")
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Avoid dereferencing NULL in introduce_domain() when called during
live update.
Coverity ID: 1665111
Fixes: f78895ad78 ("tools/xenstored: Read event channel from xenstored page")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Update get_implicit_path to return the correct value for a non-dom0
xenstored domain.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
posix.c and minios.c implement the same named functions serving slightly
different purposes.
For xenbus_map()
posix.c maps the local /dev/xen/xsd_kva
minios.c maps dom0 via grant and there is open coding for stub_domid in
map_interface.
Change xenbus_map() to map the local domain's interface. The default
grant table mapping is performed otherwise.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
The dom0_domid variable is misnamed and conflates purposes. If we have
xenstored running in a Linux domain that is not dom0, this variable
controls the lookup of /proc/xen/xsd_kva and the event channel.
Rename to store_domid to better show its purpose.
One implication of this change is that the xenstore domain is not
privileged by virtue of considering store_domid as privileged.
domain_is_unprivileged() removes the dom0_domid/store_domid check, so
xenstore domain is no longer considered privileged.
onearg_domain() is updated to return EINVAL for store_domid or priv_domid
to maintain the ability to call XS_RESUME.
xenbus_master_domid() is removed with store_domid being used instead.
Add a description of the -m/--master-domid options while
doing this.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Usually, priv_domid == dom0_domid == 0, and that is what is expected.
If we rename s/dom0_domid/store_domid/, it seems more likely we want to
actually have the priv_domid as the owner.
That leads to follow on changes to ensure that the priv_domid is created
first.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
With separate control and xenstore domains, the xenstore domain itself
is no longer privileged. Local socket connections do not have
conn->domain assigned, but domain_chk_quota() will go ahead and
dereference it. The !domid_is_unprivileged(conn->id) check usually
means the function would have already returned.
Bail out on !conn->domain to avoid faulting. This adds a similar check
to that in domain_max_chk()
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Replace dom0_init() with init_domains() which uses libxenmanage to
iterate through all existing domains, storing them in a list. The xenstore
domain is introduced first, and then all the other domains are
introduced. The xenstore domain needs to be introduced first to setup
structures needed for firing watches.
dom0_domid is updated with the xenstore domain, since it really
indicates the local domain.
priv_domid is set to the control domain. This makes it limited to a
single domain.
These features let xenstore automatically connect any existing domains,
which means it doesn't need to be done manually from init-dom0less.
For a legacy dom0, the result should be unchanged.
For a late xenstore stubdom it should also be the same, but priv_domid
would be set automatically to control domain (which default to 0
normally).
Always signal the event channel for initial domains. This gets dom0 (a
local xenstored domain) to connect.
Also always write XENSTORE_CONNECTED since we know we are connected at
this point.
To support ARM dom0less domains with xen,enhanced = "no-xenstore" a
failed introduce_domain() becomes non-fatal. Normally,
HVM_PARAM_STORE_EVTCHN is used to identify .
priv_domid from the command line is used, or the first control domain is
used.
dom0_domid will set to the last xenstore found. This will handle dom0
or dom0less, where only 1 xenstore domain can exist, or stubdom, where
dom0 and dom1 exist, and we want to take the stubdom.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Add helpers to lookup the event channel for a domid. This hides some
of the differences between dom0 and stubdom xenstored. Each version
defines its own.
It highlights the different meanings between get_xenbus_evtchn() in a
stubdom, where it looks up dom0's event channel, and dom0, where it
looks up the local event channel.
get_domain_evtchn() replaces get_xenbus_evtchn(), and
get_xenbus_evtchn() is removed from minios.c as it is inlined in the new
function.
The default return 0 will be fine as any other auto-introduced domain
will needs the event channel populated in the grant.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Make introduce_domain() use an event channel from the the xenstore page.
It is only used if non-zero. Otherwise the passed in event channel port
is used.
The is useful for a xenstored stubdom to configure domains autonomously.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Pass the live_update bool to stubdom_init() in order to be able to
handle it properly under Mini-OS.
As stubdom_init() will (re-)create the 9pfs device needed for
reading the saved state, call stubdom_init() before lu_read_state().
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
After performing a live update in stubdom environment some information
about inter-domain event channels is lost. In order to set this
information again, call xenevtchn_bind() from new_domain() in the
restore case.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
When running in a stubdom environment xenevtchn_fdopen() won't work,
as any file descriptor state is lost across kexec().
Use a wrapper to replace the call of xenevtchn_fdopen() with the
really needed xenevtchn_open() when running on top of Mini-OS.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Mini-OS doesn't support using mmap() for accessing a file. In order
to support reading the live update state from a 9pfs based file, use
fread() instead of mmap().
While adding the offset member to lu_state, change the type of "size"
to size_t in order to avoid problems with state exceeding 4GB.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Add an additional "caps" argument to the libxenmanage functions to
obtain a domains capabilities - control, hardware, and xenstore.
Update the xenstored callers at the same time.
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
Add support for XS_SET_FEATURE and XS_GET_FEATURE to xenstored.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Add per domain server features, which are initialized by the supported
features at domain introduction, or by live update from the migration
stream. This requires to add the DOMAIN_DATA record to the migration
stream, but for now it will only contain the feature word.
Advertise the Xenstore features to guests by setting the appropriate
bits in the ring page.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Add all the missing migration record structures and defines to the
xenstore_state.h header file.
Update the version of the migration stream to "2". In order to allow
receiving version 1 streams, change the version check of the header
to reject only streams with a version higher than the current known
one.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
In order to prepare xenstored supporting migration stream versions
other than 1, add a parameter to the live update command allowing to
specify the version of the migration stream.
This will allow going back from xenstored using version 2 per default
to a xenstored only accepting version 1.
For now only version 1 is supported.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
For the final step of live-update in stubdom, call kexec().
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Add the required configuration settings to enable kexec in the PVH
variant of xenstore-stubdom. This is required to support live update.
Set the number of kexec module pages to 18 in order to support using
the kexec module memory for the stubdom's 9pfs granted pages.
In Xenstore code test the CONFIG_KEXEC setting in order to determine
whether stubdom live update is supported (PV xenstore-stubdom doesn't
have live update support, as it lacks kexec).
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Use of setjmp/longjmp as removed in 2006, but the include remained.
Remove it now.
Fixes: 1bac3b49cd ("Import the current version of talloc from the Samba 3 source base")
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Instead of checking each known domain after having received a
VIRQ_DOM_EXC event, use the new xenmanage_poll_changed_domain()
function for directly getting the domid of a domain having changed
its state.
A test doing "xl shutdown" of 1000 guests has shown to reduce the
consumed cpu time of xenstored by 6% with this change applied.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Use the new unique_id of a domain in order to detect that a domain
has been replaced with another one reusing the domain-id of the old
domain.
While changing the related code, switch from "dom_invalid" to
"dom_valid" in order to avoid double negation and use "bool" as type
for it.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Replace the current use of the unstable xc_domain_getinfo_single()
interface with the stable domctl XEN_DOMCTL_get_domain_state call
via the new libxenmanage library.
This will remove the last usage of libxenctrl by Xenstore, so update
the library dependencies accordingly.
For now only do a direct replacement without using the functionality
of obtaining information about domains having changed the state.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Today the xenstored Makefile contains an unneeded reference to the
not used libxenguest library.
Remove it.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
With the introduction of 9pfs for Xenstore-stubdom it is now possible
to use a file for saving the state when doing live update.
This allows to move some environment specific actions back to the
common source file lu.c.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Juergen Gross