In the `doListFontsAndAliases` function in dixfonts.c, when a font alias
is encountered (`err == FontNameAlias`) as a result of
`list_next_font_or_alias` call, the code allocates memory for
`resolved` variable (`resolvedlen + 1` bytes) for storing target font
name. In this case, if the `malloc(resolvedlen + 1)` call fails,
`resolved` remains NULL.
Later, when check (`else if (err == FontNameAlias)`) is TRUE, the code
uses `memcpy` to copy nullable `resolved` into `tmp_pattern` without
checking if `resolved` is NULL, so there is a potential null ptr
dereference.
This commit replaces `malloc` with `XNFalloc` for allocating memory for
`resolved`. `XNFalloc` will internally check result of `malloc` and stop
program execution if allocation was failed, preventing potential NULL
dereferencing.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Mikhail Dmitrichenko <m.dmitrichenko222@gmail.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2114>
dixLookupResourceByType always overwrites the pointer passed in as the
first arg, so we shouldn't use the union it's in after that to get the
requested XID value to put in the errorValue.
Closes: #1857
Fixes: 2d7eb4a19 ("Pre-validate ChangeGC XIDs.")
Reported-by: Mouse <mouse@Rodents-Montreal.ORG>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2111>
(cherry picked from commit ac42c39145)
Reported in #1817:
xwayland-24.1.6/redhat-linux-build/../dix/property.c:584:5:
warning[-Wanalyzer-malloc-leak]: leak of ‘pAtoms’
Can happen if, and only if, XaceHookPropertyAccess() blocks access
to all properties, so that numProps ends up zero on the second loop.
Fixes: 39f337fd4 ("dix: ProcListProperties: skip unneeded work if numProps is 0")
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2078>
(cherry picked from commit ed92eae84d)
If we're swapping 4-byte integers or 2-byte integers, make sure the size
of the buffer doesn't have any bytes left over, since we won't correctly
handle those bytes.
Reported in #1817:
xwayland-24.1.6/redhat-linux-build/../dix/swaprep.c:99:22:
warning[-Wanalyzer-allocation-size]:
allocated buffer size is not a multiple of the pointee's size
xwayland-24.1.6/redhat-linux-build/../dix/swaprep.c:146:22:
warning[-Wanalyzer-allocation-size]:
allocated buffer size is not a multiple of the pointee's size
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2078>
(cherry picked from commit cf49354b60)
The wOtherInputMasks(win) macro will return NULL if
win->optional is NULL.
Reported in #1817:
xwayland-24.1.6/redhat-linux-build/../dix/gestures.c:242:9:
warning[-Wanalyzer-null-dereference]: dereference of NULL ‘inputMasks’
xwayland-24.1.6/redhat-linux-build/../dix/touch.c:765:9:
warning[-Wanalyzer-null-dereference]: dereference of NULL ‘inputMasks’
xwayland-24.1.6/redhat-linux-build/../dix/touch.c:782:9:
warning[-Wanalyzer-null-dereference]: dereference of NULL ‘inputMasks’
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2078>
(cherry picked from commit 15496a5e3d)
In the doListFontsWithInfo function in dixfonts.c, when a font alias is
encountered (err == FontNameAlias), the code saves the current state
and allocates memory for c->savedName.
If the malloc(namelen + 1) call fails, c->savedName remains NULL,
but c->haveSaved is still set to TRUE. Later, when a font is
successfully resolved (err == Successful), the code uses c->savedName
without checking if it is NULL, so there is potential null ptr
dereference. XNFalloc will check result of malloc and stop
program execution if allocation was failed.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Closes: https://gitlab.freedesktop.org/xorg/xserver/-/issues/1842
Signed-off-by: Mikhail Dmitrichenko <m.dmitrichenko222@gmail.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2062>
(cherry picked from commit dd5c2595a4)
The BigRequest extension allows requests larger than the 16-bit length
limit.
It uses integers for the request length and checks for the size not to
exceed the maxBigRequestSize limit, but does so after translating the
length to integer by multiplying the given size in bytes by 4.
In doing so, it might overflow the integer size limit before actually
checking for the overflow, defeating the purpose of the test.
To avoid the issue, make sure to check that the request size does not
overflow the maxBigRequestSize limit prior to any conversion.
The caller Dispatch() function however expects the return value to be in
bytes, so we cannot just return the converted value in case of error, as
that would also overflow the integer size.
To preserve the existing API, we use a negative value for the X11 error
code BadLength as the function only return positive values, 0 or -1 and
update the caller Dispatch() function to take that case into account to
return the error code to the offending client.
CVE-2025-49176
This issue was discovered by Nils Emmerich <nemmerich@ernw.de> and
reported by Julian Suleder via ERNW Vulnerability Disclosure.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
(cherry picked from commit 03731b326a)
This fixes a crash when we try to send focus events and dereference
FollowKeyboardWin (0x3) as WindowPtr.
A device set to XSetDeviceFocus(FollowKeyboard) is supposed to follow
the focus of the corresponding master device. During ActivateKeyboard
a slave device is detached from the master for the duration for the grab
so we don't actually have a master to follow - leaving our oldWin set to
the FollowKeyboardWin constant. This later crashes when we try to
dereference it.
Fix this by getting the current master (if any), or the saved master (if
temporarily detached due to a grab). And if failing that, use the VCK
as fallback device - that is technically wrong but it's such a niche use
case that it shouldn't matter.
Reproducer:
window = XCreateSimpleWindow(...)
deviceid = any device that is IsXExtensionKeyboard device
XSetDeviceFocus(deviceid, FollowKeyboard, ...)
XGrabDevice(deviceid, window, ...)
Fixes: f01ee198ff ("dix: don't use inputInfo.keyboard to get the focus window in ActivateKbdGrab")
Found-by: Olivier Fourdan <ofourdan@redhat.com>
Acked-by: Olivier Fourdan <ofourdan@redhat.com>
Tested-by: Olivier Fourdan <ofourdan@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1870>
(cherry picked from commit cab9017485)
When a device is removed while still frozen, the events queued for that
device remain while the device itself is freed.
As a result, replaying the events will cause a use after free.
To avoid the issue, make sure to dequeue and free any pending events on
a frozen device when removed.
CVE-2025-26600, ZDI-CAN-25871
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>
(cherry picked from commit 6e0f332ba4)
CreateCursor returns a cursor with refcount 1 - that refcount is used by
the resource system, any caller needs to call RefCursor to get their own
reference. That happens correctly for normal cursors but for our
rootCursor we keep a variable to the cursor despite not having a ref for
ourselves.
Fix this by reffing/unreffing the rootCursor to ensure our pointer is
valid.
Related to CVE-2025-26594, ZDI-CAN-25544
Reviewed-by: Olivier Fourdan <ofourdan@redhat.com>
(cherry picked from commit b0a09ba602)
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1830>
If a cursor reference count drops to 0, the cursor is freed.
The root cursor however is referenced with a specific global variable,
and when the root cursor is freed, the global variable may still point
to freed memory.
Make sure to prevent the rootCursor from being explicitly freed by a
client.
CVE-2025-26594, ZDI-CAN-25544
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
v2: Explicitly forbid XFreeCursor() on the root cursor (Peter Hutterer
<peter.hutterer@who-t.net>)
v3: Return BadCursor instead of BadValue (Michel Dänzer
<michel@daenzer.net>)
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Suggested-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1828>
(cherry picked from commit 01642f263f)
The request struct's length fields aren't used anymore - we have the
client->req_len field instead, which also is bigreq-compatible.
Also dropping now obsolete SProcNoOperation().
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1639>
(cherry picked from commit 4c3ff75772)
This script used to generated xproto header as well as a piece of source
for initializing the builtin atoms in the Xserver (MakePredeclaredAtoms()).
At least with R6.6 baseline it didn't seem to be used anymore, and - at least
since the modularization - it's completely broken and useless.
Since we now have a new generator, running directly in the build process,
this ancient script can be dropped.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1670>
(cherry picked from commit 216fc6fe83)
Previously, it was looping through sizeof(ev->valuators.mask) * 8
valuators, where valuators.mask is defined as an array of
(MAX_VALUATORS + 7) / 8 entries. Since MAX_VALUATORS is defined as 36,
this made it actually loop through 40 entries. The last 4 bits in this
array should never be set, so we should never access memory outside the
bounds of the arrays defined to be exactly MAX_VALUATORS in length, but
we can make the static analyzer happier and not waste time checking bits
that should never be set.
Found by Oracle Parfait 13.3 static analyzer:
Read outside array bounds [read-outside-array-bounds]:
In array dereference of ev->valuators.data[i] with index i
Array size is 36 elements (of 8 bytes each), index >= 0 and index <= 39
at line 741 of dix/eventconvert.c in function 'eventToDeviceEvent'.
Read outside array bounds [read-outside-array-bounds]:
In array dereference of ev->valuators.data[i] with index i
Array size is 36 elements (of 8 bytes each), index >= 0 and index <= 39
at line 808 of dix/eventconvert.c in function 'eventToRawEvent'.
Read outside array bounds [read-outside-array-bounds]:
In array dereference of ev->valuators.data_raw[i] with index i
Array size is 36 elements (of 8 bytes each), index >= 0 and index <= 39
at line 809 of dix/eventconvert.c in function 'eventToRawEvent'.
Fixes: b2ba77bac ("dix: add EventToXI2 and GetXI2Type.")
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1730>
(cherry picked from commit b65eea43dd)
Found by Oracle Parfait 13.3 static analyzer:
Buffer Overflow in STD C function [buffer-overflow-call-stdc]:
Buffer overflow in call to memcpy. Buffer &bev->buttons[4] of
size 24 is written at an offset of 28
Array size is 28 bytes, index is 32
at line 743 of dix/enterleave.c in function
'DeliverStateNotifyEvent'.
Fixes: a85f0d6b9 ("Xi: fix use of button->down - bitflags instead of int arrays.")
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1730>
(cherry picked from commit 4b073d65bb)
If the compiler knows of a better algorithm for counting the number of
bits set in a word for the target CPU, let it use that, instead of the
classic algorithm optimized for PDP-6.
Based on xorg/lib/libxext@490a25e6f8a4d2482af4364c700b68ad11a4d10b
v2: make old version static inline, stop exporting after !1695
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1674>
(cherry picked from commit 45c485bfdf)
Make it clear what exactly this parameter is for.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
(cherry picked from commit e7c225aef6)
Allow NULL parameters to be passed to FreeGrab(), so callers don't all
need to check on their own anymore.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
(cherry picked from commit 48cee2fd22)
This function is only called once in the same source file, no external callers
at all. So, it doesn't need to be visible outside that file, and we can allow
the compiler to do whatever fancy optimizations it might wanna do.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
(cherry picked from commit 93856053b7)
Clears warning from gcc 14.1:
../dix/resource.c: In function ‘HashResourceID’:
../dix/resource.c:691:44: warning: left shift of negative value
[-Wshift-negative-value]
691 | return (id ^ (id >> numBits)) & ~((~0) << numBits);
| ^~
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1673>
(cherry picked from commit 26a7ab09ea)
No real harm, but clears warning from gcc 14.1:
../dix/property.c: In function ‘ProcListProperties’:
..//dix/property.c:605:27: warning: dereference of NULL ‘temppAtoms’
[CWE-476] [-Wanalyzer-null-dereference]
605 | *temppAtoms++ = pProp->propertyName;
| ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1673>
(cherry picked from commit 39f337fd49)
It shouldn't matter, since it would have a length of 0, but it
clears warnings from gcc 14.1:
../dix/property.c: In function ‘dixChangeWindowProperty’:
../dix/property.c:287:9: warning: use of possibly-NULL ‘data’ where
non-null expected [CWE-690] [-Wanalyzer-possible-null-argument]
287 | memcpy(data, value, totalSize);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../dix/property.c:324:13: warning: use of possibly-NULL ‘data’ where
non-null expected [CWE-690] [-Wanalyzer-possible-null-argument]
324 | memcpy(data, value, totalSize);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1673>
(cherry picked from commit 10cafd0bbe)
Clears warning from gcc 14.1:
../dix/dixfonts.c: In function ‘SetFontPath’:
../dix/dixfonts.c:1697:28: warning: use of uninitialized value ‘bad’
[CWE-457] [-Wanalyzer-use-of-uninitialized-value]
1697 | client->errorValue = bad;
| ~~~~~~~~~~~~~~~~~~~^~~~~
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1673>
(cherry picked from commit 1a86fba0d9)
Clears warning from gcc 14.1:
../dix/dixfonts.c:1352:15: warning: use of uninitialized value ‘*c.data’
[CWE-457] [-Wanalyzer-use-of-uninitialized-value]
1352 | free(c->data);
| ~^~~~~~
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1673>
(cherry picked from commit d78836a3a6)
We alread have several of these calls, that aren't interested in result value,
explicitly casting to void. Fixing this up for the remaining ones.
This is helpful for the human reader as well as quality analysis tools.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1648>
(cherry picked from commit f26f17c66a)
This has been nothing but an alias for two decades now (somewhere in R6.6),
so there doesn't seem to be any practical need for this indirection.
The macro still needs to remain, as long as (external) drivers still using it.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1529>
(cherry picked from commit a1fd7e7ba5)
The xnfreallocarray was added along (and just as an alias to) XNFreallocarray
back a decade ago. It's just used in a few places and it's only saves us from
passing the first parameter (NULL), so the actual benefit isn't really huge.
No (known) driver is using it, so the macro can be dropped entirely.
Fixes: ae75d50395
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1529>
(cherry picked from commit 61233adbca)
Clears -Wcalloc-transposed-args warnings from gcc 14.1, such as:
../dix/main.c:165:42: warning: ‘calloc’ sizes specified with ‘sizeof’ in the
earlier argument and not in the later argument [-Wcalloc-transposed-args]
165 | serverClient = calloc(sizeof(ClientRec), 1);
| ^~~~~~~~~
../dix/main.c:165:42: note: earlier argument should specify number of
elements, later size of each element
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1606>
(cherry picked from commit 522f469fe9)
For now, new selection objects are only created in ProcSetSelectionOwner()
when dixLookupSelection() can't find the requested one (returns BadMatch).
When somebody's trying to listen on a not-yet existing selection, via
XFixesSelectSelectionInput() -- XFIXES:SelectSelectionInput message -- he's
also getting BadMatch. The spec isn't explicitly clear on the exact behaviour
in those specific situations: it doesn't tell anything about selection's
lifetimes (when are they actually *created* or *destroyed*), just about their
ownership.
But there are real-world clients not expecting an error here and crashing
with a BadMatch error.
Since the spec doesn't mandate any Selection lifetime, it's safe to assume,
they can be created as-needed (as other related code paths already do).
Doing so ensures such an error cannot happen anymore.
XACE consumers get properly notified by the new Selection object creation
(eg. SElinux is attaching it's private data to it). And all callers already
prepared to get a cleared Selection object, because that's always been a
perfectly normal situation - Selection objects never get removed again,
just cleared.
Fixes: 601fd0fd8 - xfixes/xace: fix pointer type mismatch on XFixesSelectSelectionInput()
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1574>
(cherry picked from commit 6a1d730006)
As soon as winapi headers are included, we're running into a name clash
on UpdateColors(), since winapi has a function by the same name.
Trivial fix simply renaming our own UpdateColors() function.
../dix/colormap.c:110:13: error: conflicting types for ‘UpdateColors’
110 | static void UpdateColors(ColormapPtr /*pmap */
| ^~~~~~~~~~~~
In file included from /usr/share/mingw-w64/include/windows.h:71,
from /usr/share/mingw-w64/include/winsock2.h:23,
from /usr/i686-w64-mingw32/include/X11/Xwinsock.h:57,
from ../os/osdep.h:138,
from ../dix/colormap.c:57:
/usr/share/mingw-w64/include/wingdi.h:3202:28: note: previous declaration of ‘UpdateColors’ was here
3202 | WINGDIAPI WINBOOL WINAPI UpdateColors(HDC hdc);
| ^~~~~~~~~~~~
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1351>
(cherry picked from commit d8cbcfd601)
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>
(cherry picked from commit 305f2d59d8)
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>
(cherry picked from commit 51d8bcfc0d)
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>
(cherry picked from commit 47d6c3ad75)
