Using calloc() instead of malloc() as preventive measure, so there
never can be any hidden bugs or leaks due uninitialized memory.
The extra cost of using this compiler intrinsic should be practically
impossible to measure - in many cases a good compiler can even deduce
if certain areas really don't need to be zero'd (because they're written
to right after allocation) and create more efficient machine code.
The code pathes in question are pretty cold anyways, so it's probably
not worth even thinking about potential extra runtime costs.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
The computation of the length in XkbSizeKeySyms() differs from what is
actually written in XkbWriteKeySyms(), leading to a heap overflow.
Fix the calculation in XkbSizeKeySyms() to match what kbWriteKeySyms()
does.
CVE-2025-26596, ZDI-CAN-25543
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1828>
These are only used inside xkb/*, so no need to keep them exported.
Also replacing some macros by inline functions in order to improve
type-safety and debugging, and adding documentation.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1729>
This function has only one caller in xkb.c, so no need to keep it exported,
can be moved over into xkb.c and made static.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1729>
The authorative source of the request frame size is client->req_len,
especially with big requests larger than 2^18 bytes.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1639>
The _XkbSetCompatMap() function attempts to resize the `sym_interpret`
buffer.
However, It didn't update its size properly. It updated `num_si` only,
without updating `size_si`.
This may lead to local privilege escalation if the server is run as root
or remote code execution (e.g. x11 over ssh).
CVE-2024-9632, ZDI-CAN-24756
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Tested-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: José Expósito <jexposit@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1733>
fix warning on unused variable:
> ../xkb/xkb.c:3576:18: warning: variable 'extDevReason' set but not used [-Wunused-but-set-variable]
> unsigned int extDevReason;
^
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1426>
The symbol controls whether to include dix-config.h, and it's always set,
thus we don't need it (and dozens of ifdef's) anymore.
This commit only removes them from our own source files, where we can
guarantee that dix-config.h is present - leaving the (potentially exported)
headers untouched.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
If XkbComputeGetGeometryReplySize() returns an error, the XkbGeometryRec won't
be freed, since we're bailing out too early and not calling XkbSendGeometry().
Having XkbSendGeometry() responsible for freeing that struct is unnecessarily
complicated anyways, so move that to ProcXkbGetGeometry() and do it also when
XkbComputeGetGeometryReplySize() failed.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1622>
he generic XaceHook() call isn't typesafe (und unnecessarily slow).
Better add an explicit function, just like we already have for others.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1556>
The generic XaceHook() call isn't typesafe (und unnecessarily slow).
Better add an explicit function, just like we already have for others.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1556>
No need to define XKBSRV_NEED_FILE_FUNCS, for about 15 years now
(since XKBsrv.h isn't used anymore), so drop it.
Fixes: e5f002edde
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
_XkbCheckRequestBounds assumes that from..to is at least one byte.
However, request strings can be empty, causing spurious failures in
XkbGetKbdByName calls. To avoid this, before checking bounds make
sure that the length is nonzero.
GetCountedString did a check for the whole string to be within the
request buffer but not for the initial 2 bytes that contain the length
field. A swapped client could send a malformed request to trigger a
swaps() on those bytes, writing into random memory.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Each string length field was accessed before checking whether that byte
was actually part of the client request. No real harm here since it
would immediately fail with BadLength anyway, but let's be correct here.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
This request accessed &stuff[1] before length-checking everything. The
check was performed afterwards so invalid requests would return
BadLength anyway, but let's do this before we actually access the
memory.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
No validation of the various fields on that report were done, so a
malicious client could send a short request that claims it had N
sections, or rows, or keys, and the server would process the request for
N sections, running out of bounds of the actual request data.
Fix this by adding size checks to ensure our data is valid.
ZDI-CAN 16062, CVE-2022-2319.
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
XKB often uses a FooCheck and Foo function pair, the former is supposed
to check all values in the request and error out on BadLength,
BadValue, etc. The latter is then called once we're confident the values
are good (they may still fail on an individual device, but that's a
different topic).
In the case of XkbSetDeviceInfo, those functions were incorrectly
named, with XkbSetDeviceInfo ending up as the checker function and
XkbSetDeviceInfoCheck as the setter function. As a result, the setter
function was called before the checker function, accessing request
data and modifying device state before we ensured that the data is
valid.
In particular, the setter function relied on values being already
byte-swapped. This in turn could lead to potential OOB memory access.
Fix this by correctly naming the functions and moving the length checks
over to the checker function. These were added in 87c64fc5b0 to the
wrong function, probably due to the incorrect naming.
Fixes ZDI-CAN 16070, CVE-2022-2320.
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
Introduced in c06e27b2f6
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Most similar loops here use a pointer that advances with each loop
iteration, let's do the same here for consistency.
No functional changes.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Olivier Fourdan <ofourdan@redhat.com>
Sick of fighting vim and git from trying to add this fix with every
commit iteration...
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Olivier Fourdan <ofourdan@redhat.com>
This header merely defines the various protocol request handlers, so
let's rename it to something less generic and remove its include from
all the files that don't actually need it (which is almost all of them).
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Olivier Fourdan <ofourdan@redhat.com>
As the comment says:
"symsPerKey/mapWidths must be filled regardless of client-side flags"
so we always have to call CheckKeyTypes which will notably fill mapWidths
and nTypes. That is needed for CheckKeySyms to work since it checks the
width. Without it, any request with XkbKeySymsMask but not
XkbKeyTypesMask will fail because of the missing width information, for
instance this:
XkbDescPtr xkb;
if (!(xkb = XkbGetMap (dpy, XkbKeyTypesMask|XkbKeySymsMask, XkbUseCoreKbd))) {
fprintf (stderr, "ERROR getting map\n");
exit(1);
}
XFlush (dpy);
XSync (dpy, False);
XkbMapChangesRec changes = { .changed = 0 };
int oneGroupType[XkbNumKbdGroups] = { XkbOneLevelIndex };
if (XkbChangeTypesOfKey(xkb, keycode, 1, XkbGroup1Mask, oneGroupType, &changes)) {
fprintf(stderr, "ERROR changing type of key\n");
exit(1);
}
XkbKeySymEntry(xkb,keycode,0,0) = keysym;
if (!XkbChangeMap(dpy,xkb,&changes)) {
fprintf(stderr, "ERROR changing map\n");
exit(1);
}
XkbFreeKeyboard (xkb, 0, TRUE);
XFlush (dpy);
XSync (dpy, False);
This had being going under the radar since about ever until commit
de940e06f8 ("xkb: fix key type index check
in _XkbSetMapChecks") fixed checking the values of kt_index, which was
previously erroneously ignoring errors and ignoring all other checks, just
because nTypes was not set, precisely because CheckKeyTypes was not called.
Note: yes, CheckKeyTypes is meant to be callable without XkbKeyTypesMask, it
does properly check for that and just fills nTypes and mapWidths in that
case.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
The previous if/else condition resulted in us always setting the key
type count to the current number of key types. Split this up correctly.
Regression introduced in de940e06f8Fixes#1249
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Commit 446ff2d317 added checks to
prevalidate the size of incoming SetMap requests.
That commit checks for the XkbSetMapResizeTypes flag to be set before
allowing key types data to be processed.
key types data can be changed or even just sent wholesale unchanged
without the number of key types changing, however. The check for
XkbSetMapResizeTypes rejects those legitimate requests. In particular,
XkbChangeMap never sets XkbSetMapResizeTypes and so always fails now
any time XkbKeyTypesMask is in the changed mask.
This commit drops the check for XkbSetMapResizeTypes in flags when
prevalidating the request length.
xkb.c: In function ‘ProcXkbSetMap’:
xkb.c:2747:5: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
2747 | DeviceIntPtr master = GetMaster(dev, MASTER_KEYBOARD);
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Avoid out of bounds memory accesses on too short request.
ZDI-CAN 11572 / CVE-2020-14360
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
Signed-off-by: Matthieu Herrb <matthieu@herrb.eu>
ZDI-CAN 11389 / CVE-2020-25712
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
Signed-off-by: Matthieu Herrb <matthieu@herrb.eu>
CVE-2020-14345 / ZDI 11428
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
Signed-off-by: Matthieu Herrb <matthieu@herrb.eu>
This code block was moved from a function that returns 0 for failure to a
function that returns 0 for Success in commit
649293f6b6. Change the return value to
BadValue to match the other checks in _XkbSetMapChecks.
Set nTypes to xkb->map->num_types when XkbKeyTypesMask is not set, to
allow requests with the XkbKeyTypesMask flag unset in stuff->present to
succeed.
Fixes a potential heap smash when client->swapped is true, because the
remainder of the request will not be swapped after "return 0", but
_XkbSetMap will be called anyway (because 0 is Success).
Signed-off-by: Peter Harris <pharris@opentext.com>
The server swaps part of the request in _XkbSetMapChecks instead of
SProcXkbSetMap (presumably because walking the XkbSetMap request is hard,
and we don't want to maintain another copy of that code).
Swap the first time _XkbSetMapChecks is called, not the second time.
Signed-off-by: Peter Harris <pharris@opentext.com>
XKB stores some stuff in the ClientRec that, style-wise, should probably
be in a client private. vMinor tracks the client's idea of the XKB
minor version, but is never read, we can just nuke it. vMajor is only
used for a bug-compat workaround for X11R6.0-vintage clients. We're
only using though (1<<4) for xkbClientFlags in the protocol, so we can
pack that field down to a u8 and store the bug-compat flag there.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Julien Cristau <jcristau@debian.org>
Regression introduce by ac164e5887 which calls
XkbUpdateAllDeviceIndicators() with two NULL arguments. A few layers down into
the stack and we triggered a NULL-pointer dereference. In theory a NULL cause
is acceptable since we don't actually change modifier state here. Instead of
updating all places to check for NULL just set the cause to the client
request and go to the pub.
https://bugs.freedesktop.org/show_bug.cgi?id=96384
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Julien Cristau <jcristau@debian.org>
Reviewed-by: Daniel Stone <daniels@collabora.com>
When NumLock is on and a new keymap is applied, the next modifier state
change will turn off that LED (but leave the state enabled). The cause
for this is a bit convoluted:
* the SLI explicitState is copied from the current state in
ProcXkbGetKbdByName. Thus, if NumLock is on, that state is 0x2.
* on the next modifier key press (e.g. Shift), XkbApplyState() calls into
XkbUpdateIndicators() -> XkbUpdateLedAutoState() to update SLIs (if any)
for the currently changed modifier. But it does so with a mask only for
the changed modifier (i.e. for Shift).
* XkbUpdateLedAutoState() calculates the state based on this mask and
ends up with 0 because we don't have a Shift LED and we masked out the
others.
* XkbUpdateLedAutoState() compares that state with the previous state
(which is still 0x2) and then proceeds to turn the LED off
This doesn't happen in the normal case because either the mask
encompasses all modifiers or the state matches of the masked-out
modifiers matches the old state.
Avoid this issue by forcing an SLI update after changing the keymap.
This updates the sli->effectiveState and thus restores everything to
happy working order.
https://bugzilla.redhat.com/show_bug.cgi?id=1047151
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Ensure that the given strings length in an XkbSetGeometry request remain
within the limits of the size of the request.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
The XkbSetGeometry request embeds data which needs to be swapped when the
server and the client have different endianess.
_XkbSetGeometry() invokes functions that swap these data directly in the
input buffer.
However, ProcXkbSetGeometry() may call _XkbSetGeometry() more than once
(if there is more than one keyboard), thus causing on swapped clients the
same data to be swapped twice in memory, further causing a server crash
because the strings lengths on the second time are way off bounds.
To allow _XkbSetGeometry() to run reliably more than once with swapped
clients, do not swap the data in the buffer, use variables instead.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
When _XkbCheckAtoms returns NULL for an error, it always sets the
error return code, but GCC can't figure that out, so just initialize
the local variable, 'bad', in _XkbSetNamesCheck to eliminate the warning.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
This will also make it useful for cases when we have a new keymap to
apply to a device but don't have a source device.
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Enrico Weigelt, metux IT consult
Olivier Fourdan
Matthieu Herrb
FeepingCreature
Peter Hutterer
Samuel Thibault
Ray Strode
Peter Harris
Dave Airlie
Samir Benmendil
Adam Jackson
Alan Coopersmith
Keith Packard
Rui Matos