Commit graph

658 commits

Author SHA1 Message Date
Peter Hutterer
87df8bcc19 Zero out structs to avoid leaking information via padding
Structs that are sent to the client may leak data via unititialized
padding bytes. Let's not do that.

Co-Authored-by: Claude Code <noreply@anthropic.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2185>
2026-04-24 01:14:55 +00:00
Mikhail Dmitrichenko
5dfb435c1d xkb: fix potential buff overflow in XkbVModIndexText for XkbCFile format
len calculation and strncpy limit were off by one when prefixing
"vmod_" to the virtual modifier name. This could write the final
NULL one byte past the allocated buffer from tbGetBuffer().

Use proper allocation len for prefix to avoid writing out-of-bounds.

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/2175>
2026-04-15 23:42:25 +00:00
Mikhail Dmitrichenko
dd8b8cf49d xkb: fix incorrect size check when growing doodads in a section
In XkbAddGeomDoodad(), when adding a doodad to a specific section
(section != NULL), there is a comparison between section->num_doodads
and geom->sz_doodads instead of the section's own section->sz_doodads.

The else branch (global geometry doodads) was already correct.

Compare section->num_doodads against section->sz_doodads to prevent
a potential out-of-bounds.

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/2174>
2026-04-15 08:53:34 +00:00
Olivier Fourdan
d38c563fab xkb: Add more _XkbCheckRequestBounds()
Similar to the recent fixes, add more _XkbCheckRequestBounds() to the
functions that loop over the request data, i.e.:

 * CheckKeySyms()
 * CheckKeyActions()
 * CheckKeyBehaviors()
 * CheckVirtualMods()
 * CheckKeyExplicit()
 * CheckVirtualModMap()
 * _XkbSetMapChecks()

All these are static functions so we can add the client to the parameters
without breaking any API.

See also:
CVE-2026-34003, ZDI-CAN-28736, CVE-2026-34002, ZDI-CAN-28737

v2: Check for "nSyms != 0" in CheckKeySyms() to avoid false positives.

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2176>
2026-04-14 14:43:53 +02:00
Olivier Fourdan
b85b00dd7b xkb: Add additional bound checking in CheckKeyTypes()
The function CheckKeyTypes() will loop over the client's request but
won't perform any additional bound checking to ensure that the data
read remains within the request bounds.

As a result, a specifically crafted request may cause CheckKeyTypes() to
read past the request data, as reported by valgrind:

  == Invalid read of size 2
  ==    at 0x5A3D1D: CheckKeyTypes (xkb.c:1694)
  ==    by 0x5A6A9C: _XkbSetMapChecks (xkb.c:2515)
  ==    by 0x5A759E: ProcXkbSetMap (xkb.c:2736)
  ==    by 0x5BF832: SProcXkbSetMap (xkbSwap.c:245)
  ==    by 0x5C05ED: SProcXkbDispatch (xkbSwap.c:501)
  ==    by 0x4A20DF: Dispatch (dispatch.c:551)
  ==    by 0x4B03B4: dix_main (main.c:277)
  ==    by 0x428941: main (stubmain.c:34)
  ==  Address is 30 bytes after a block of size 28,672 in arena "client"
  ==
  == Invalid read of size 2
  ==    at 0x5A3AB6: CheckKeyTypes (xkb.c:1669)
  ==    by 0x5A6A9C: _XkbSetMapChecks (xkb.c:2515)
  ==    by 0x5A759E: ProcXkbSetMap (xkb.c:2736)
  ==    by 0x5BF832: SProcXkbSetMap (xkbSwap.c:245)
  ==    by 0x5C05ED: SProcXkbDispatch (xkbSwap.c:501)
  ==    by 0x4A20DF: Dispatch (dispatch.c:551)
  ==    by 0x4B03B4: dix_main (main.c:277)
  ==    by 0x428941: main (stubmain.c:34)
  ==  Address is 2 bytes after a block of size 28,672 alloc'd
  ==    at 0x4848897: realloc (vg_replace_malloc.c:1804)
  ==    by 0x5E357A: ReadRequestFromClient (io.c:336)
  ==    by 0x4A1FAB: Dispatch (dispatch.c:519)
  ==    by 0x4B03B4: dix_main (main.c:277)
  ==    by 0x428941: main (stubmain.c:34)
  ==
  == Invalid write of size 2
  ==    at 0x5A3AD7: CheckKeyTypes (xkb.c:1669)
  ==    by 0x5A6A9C: _XkbSetMapChecks (xkb.c:2515)
  ==    by 0x5A759E: ProcXkbSetMap (xkb.c:2736)
  ==    by 0x5BF832: SProcXkbSetMap (xkbSwap.c:245)
  ==    by 0x5C05ED: SProcXkbDispatch (xkbSwap.c:501)
  ==    by 0x4A20DF: Dispatch (dispatch.c:551)
  ==    by 0x4B03B4: dix_main (main.c:277)
  ==    by 0x428941: main (stubmain.c:34)
  ==  Address is 2 bytes after a block of size 28,672 alloc'd
  ==    at 0x4848897: realloc (vg_replace_malloc.c:1804)
  ==    by 0x5E357A: ReadRequestFromClient (io.c:336)
  ==    by 0x4A1FAB: Dispatch (dispatch.c:519)
  ==    by 0x4B03B4: dix_main (main.c:277)
  ==    by 0x428941: main (stubmain.c:34)
  ==

To avoid that issue, add additional bounds checking within the loops by
calling _XkbCheckRequestBounds() and report an error if we are to read
past the client's request.

CVE-2026-34003, ZDI-CAN-28736

This vulnerability was discovered by:
Jan-Niklas Sohn working with TrendAI Zero Day Initiative

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2176>
2026-04-14 14:43:53 +02:00
Olivier Fourdan
f056ce1cc9 xkb: Fix out-of-bounds read in CheckModifierMap()
As reported by valgrind:

  == Conditional jump or move depends on uninitialised value(s)
  ==    at 0x547E5B: CheckModifierMap (xkb.c:1972)
  ==    by 0x54A086: _XkbSetMapChecks (xkb.c:2574)
  ==    by 0x54A845: ProcXkbSetMap (xkb.c:2741)
  ==    by 0x556EF4: ProcXkbDispatch (xkb.c:7048)
  ==    by 0x454A8C: Dispatch (dispatch.c:553)
  ==    by 0x462CEB: dix_main (main.c:274)
  ==    by 0x405EA7: main (stubmain.c:34)
  ==  Uninitialised value was created by a heap allocation
  ==    at 0x4840B26: malloc (vg_replace_malloc.c:447)
  ==    by 0x592D5A: AllocateInputBuffer (io.c:981)
  ==    by 0x591F77: InsertFakeRequest (io.c:516)
  ==    by 0x45CA27: NextAvailableClient (dispatch.c:3629)
  ==    by 0x58FA81: AllocNewConnection (connection.c:628)
  ==    by 0x58FC70: EstablishNewConnections (connection.c:692)
  ==    by 0x58FFAA: HandleNotifyFd (connection.c:809)
  ==    by 0x593F42: ospoll_wait (ospoll.c:660)
  ==    by 0x58B9B6: WaitForSomething (WaitFor.c:208)
  ==    by 0x4548AC: Dispatch (dispatch.c:493)
  ==    by 0x462CEB: dix_main (main.c:274)
  ==    by 0x405EA7: main (stubmain.c:34)

The issue is that the loop in CheckModifierMap() reads from wire without
verifying that the data is within the request bounds.

The req->totalModMapKeys value could exceed the actual data provided,
causing reads of uninitialized memory.

To fix that issue, we add a bounds check using _XkbCheckRequestBounds,
but for that, we need to also pass a ClientPtr parameter, which is not
a problem since CheckModifierMap() is a private, static function.

CVE-2026-34002, ZDI-CAN-28737

This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2176>
2026-04-14 14:43:53 +02:00
Olivier Fourdan
81b6a34f90 xkb: Fix bounds check in _CheckSetGeom()
As reported by valgrind:

  == Conditional jump or move depends on uninitialised value(s)
  ==    at 0x5CBE66: SrvXkbAddGeomKeyAlias (XKBGAlloc.c:585)
  ==    by 0x5AC7D5: _CheckSetGeom (xkb.c:5607)
  ==    by 0x5AC952: _XkbSetGeometry (xkb.c:5643)
  ==    by 0x5ACB58: ProcXkbSetGeometry (xkb.c:5684)
  ==    by 0x5B0DAC: ProcXkbDispatch (xkb.c:7070)
  ==    by 0x4A28C5: Dispatch (dispatch.c:553)
  ==    by 0x4B0B24: dix_main (main.c:274)
  ==    by 0x42915E: main (stubmain.c:34)
  ==  Uninitialised value was created by a heap allocation
  ==    at 0x4840B26: malloc (vg_replace_malloc.c:447)
  ==    by 0x5E13B0: AllocateInputBuffer (io.c:981)
  ==    by 0x5E05CD: InsertFakeRequest (io.c:516)
  ==    by 0x4AA860: NextAvailableClient (dispatch.c:3629)
  ==    by 0x5DE0D7: AllocNewConnection (connection.c:628)
  ==    by 0x5DE2C6: EstablishNewConnections (connection.c:692)
  ==    by 0x5DE600: HandleNotifyFd (connection.c:809)
  ==    by 0x5E2598: ospoll_wait (ospoll.c:660)
  ==    by 0x5DA00C: WaitForSomething (WaitFor.c:208)
  ==    by 0x4A26E5: Dispatch (dispatch.c:493)
  ==    by 0x4B0B24: dix_main (main.c:274)
  ==    by 0x42915E: main (stubmain.c:34)

Each key alias entry contains two key names (the alias and the real key
name), each of size XkbKeyNameLength.

The current bounds check only validates the first name, allowing
XkbAddGeomKeyAlias to potentially read uninitialized memory when
accessing the second name at &wire[XkbKeyNameLength].

To fix this, change the value to check to use 2 * XkbKeyNameLength to
validate the bounds.

CVE-2026-34000, ZDI-CAN-28679

This vulnerability was discovered by:
Jan-Niklas Sohn working with TrendAI Zero Day Initiative

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2176>
2026-04-14 14:43:53 +02:00
Peter Harris
b024ae1749 xkb: fix buffer re-use in _XkbSetCompatMap
If the "compat" buffer has previously been truncated, there will be
unused space in the buffer. The code uses this space, but does not
update the number of valid entries in the buffer.

In the best case, this leads to the new compat entries being ignored. In the
worst case, if there are any "skipped" compat entries, the number of
valid entries will be corrupted, potentially leading to a buffer read
overrun when processing a future request.

Set the number of used "compat" entries when re-using previously
allocated space in the buffer.

CVE-2026-33999, ZDI-CAN-28593

This vulnerability was discovered by:
Jan-Niklas Sohn working with TrendAI Zero Day Initiative

Signed-off-by: Peter Harris <pharris2@rocketsoftware.com>
Acked-by: Olivier Fourdan <ofourdan@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2176>
2026-04-14 14:43:53 +02:00
Alan Coopersmith
97cf051dfc xkb: plug memory leaks in InitKeyboardDeviceStructInternal() error paths
Reported in #1817:
xwayland-24.1.6/redhat-linux-build/../xkb/xkbInit.c:527:5:
  warning[-Wanalyzer-malloc-leak]: leak of ‘rmlvo_dflts.layout’
xwayland-24.1.6/redhat-linux-build/../xkb/xkbInit.c:527:5:
  warning[-Wanalyzer-malloc-leak]: leak of ‘rmlvo_dflts.model’
xwayland-24.1.6/redhat-linux-build/../xkb/xkbInit.c:527:5:
  warning[-Wanalyzer-malloc-leak]: leak of ‘rmlvo_dflts.options’
xwayland-24.1.6/redhat-linux-build/../xkb/xkbInit.c:527:5:
  warning[-Wanalyzer-malloc-leak]: leak of ‘rmlvo_dflts.rules’
xwayland-24.1.6/redhat-linux-build/../xkb/xkbInit.c:527:5:
  warning[-Wanalyzer-malloc-leak]: leak of ‘rmlvo_dflts.variant’

Fixes: 56a5955c8 ("xkb: strdup the values returned by XkbGetRulesDflts")
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2169>
2026-04-11 18:12:24 +00:00
Alan Coopersmith
4d0ecf0e0c xkb: handle -Wanalyzer-null-dereference in XkbDDXLoadKeymapByNames()
Reported in #1817:
xwayland-24.1.6/redhat-linux-build/../xkb/ddxLoad.c:390:20:
 warning[-Wanalyzer-null-dereference]: dereference of NULL ‘keybd’

Fixes: cf20df39c ("XKB: Actually explain keymap failures")
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2169>
2026-04-11 18:12:24 +00:00
Diego Viola
7e7d1f027f treewide: fix typos
Signed-off-by: Diego Viola <diego.viola@gmail.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2138>
2026-03-14 16:52:19 +00:00
Diego Viola
e8f4522312 Fix typos
Signed-off-by: Diego Viola <diego.viola@gmail.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2134>
2026-03-03 06:50:01 -03:00
Julian Orth
aaa8d5a955 xwayland: don't allow clients to modify the keymap
Xwayland has no way to affect the keymap of the compositor. If clients
modify the keymap, it will stay out of sync with the compositor until
some unspecified time in the future when the compositor sends the keymap
again, which might be never, requiring Xwayland to be restarted.

Signed-off-by: Julian Orth <ju.orth@gmail.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1953>
2026-02-19 13:52:28 +01:00
Pierre Le Marre
c49cbc176a xkb: Fix serialization of key type without level names
Before this commit the count of key type level names was wrongly set
in `XkbGetNames`: for key type without names, it was set to the level
count, while it should be 0:
- `XkbComputeGetNamesReplySize()` does not account key type without
  level names;
- `XkbSendNames()` does not write any level entry for key types without
  level names.

This causes a mismatch offset while parsing the response and its
processing would ultimately fail.

Fixed by setting the correct level name count: 0 if there is no level
name, else the number of levels.

Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2082>
2026-02-14 13:06:31 -08:00
Pierre Le Marre
12605989af xkb: Fix key type without level names in XkbCopyKeymap
A key type that has no level names is legit. Before this commit,
`XkbCopyKeymap` would make such level inconsistent by setting its
number of levels to 0 while keeping its map entries. It suffices
to clear the names array.

Fixed by copying the level count from the source type.

WARNING: this will trigger an error in `XkbGetNames`, which worked
before this commit only by chance. This is fixed in the next commit.

Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2082>
2026-02-14 13:06:31 -08:00
Alexander Melnyk
a9ee6b7326 xkb: Fix locked/latched indicator desync across multiple keyboards
When a group indicator (or a latched indicator of any kind) is defined,
e.g.:
  indicator "Scroll Lock" { groups = Group2; }
the logical and physical indicator state may desync across multiple
connected keyboards.

This is caused by XkbPushLockedStateToSlaves only pushing locked_mods to
the slave devices. Pushing locked_group (as well as latched groups/mods)
along with locked_mods resolves the issue.

The issue is not observed with API calls because a different code path
is taken (avoiding XkbPushLockedStateToSlaves altogether).

Signed-off-by: Alexander Melnyk <inboxnumberzero@zoho.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2120>
(cherry picked from commit 36a7fdd315)
2026-02-01 17:53:18 -08:00
Olivier Fourdan
375965221a xkb: Prevent overflow in XkbSetCompatMap()
The XkbCompatMap structure stores its "num_si" and "size_si" fields
using an unsigned short.

However, the function _XkbSetCompatMap() will store the sum of the
input data "firstSI" and "nSI" in both XkbCompatMap's "num_si" and
"size_si" without first checking if the sum overflows the maximum
unsigned short value, leading to a possible overflow.

To avoid the issue, check whether the sum does not exceed the maximum
unsigned short value, or return a "BadValue" error otherwise.

CVE-2025-62231, ZDI-CAN-27560

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: Michel Dänzer <mdaenzer@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2086>
(cherry picked from commit 475d9f49ac)
2026-01-25 10:40:03 -08:00
Olivier Fourdan
6efbdd789e xkb: Free the XKB resource when freeing XkbInterest
XkbRemoveResourceClient() would free the XkbInterest data associated
with the device, but not the resource associated with it.

As a result, when the client terminates, the resource delete function
gets called and accesses already freed memory:

 | Invalid read of size 8
 |   at 0x5BC0C0: XkbRemoveResourceClient (xkbEvents.c:1047)
 |   by 0x5B3391: XkbClientGone (xkb.c:7094)
 |   by 0x4DF138: doFreeResource (resource.c:890)
 |   by 0x4DFB50: FreeClientResources (resource.c:1156)
 |   by 0x4A9A59: CloseDownClient (dispatch.c:3550)
 |   by 0x5E0A53: ClientReady (connection.c:601)
 |   by 0x5E4FEF: ospoll_wait (ospoll.c:657)
 |   by 0x5DC834: WaitForSomething (WaitFor.c:206)
 |   by 0x4A1BA5: Dispatch (dispatch.c:491)
 |   by 0x4B0070: dix_main (main.c:277)
 |   by 0x4285E7: main (stubmain.c:34)
 | Address 0x1893e278 is 184 bytes inside a block of size 928 free'd
 |   at 0x4842E43: free (vg_replace_malloc.c:989)
 |   by 0x49C1A6: CloseDevice (devices.c:1067)
 |   by 0x49C522: CloseOneDevice (devices.c:1193)
 |   by 0x49C6E4: RemoveDevice (devices.c:1244)
 |   by 0x5873D4: remove_master (xichangehierarchy.c:348)
 |   by 0x587921: ProcXIChangeHierarchy (xichangehierarchy.c:504)
 |   by 0x579BF1: ProcIDispatch (extinit.c:390)
 |   by 0x4A1D85: Dispatch (dispatch.c:551)
 |   by 0x4B0070: dix_main (main.c:277)
 |   by 0x4285E7: main (stubmain.c:34)
 | Block was alloc'd at
 |   at 0x48473F3: calloc (vg_replace_malloc.c:1675)
 |   by 0x49A118: AddInputDevice (devices.c:262)
 |   by 0x4A0E58: AllocDevicePair (devices.c:2846)
 |   by 0x5866EE: add_master (xichangehierarchy.c:153)
 |   by 0x5878C2: ProcXIChangeHierarchy (xichangehierarchy.c:493)
 |   by 0x579BF1: ProcIDispatch (extinit.c:390)
 |   by 0x4A1D85: Dispatch (dispatch.c:551)
 |   by 0x4B0070: dix_main (main.c:277)
 |   by 0x4285E7: main (stubmain.c:34)

To avoid that issue, make sure to free the resources when freeing the
device XkbInterest data.

CVE-2025-62230, ZDI-CAN-27545

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: Michel Dänzer <mdaenzer@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2086>
(cherry picked from commit 10c94238bd)
2026-01-25 10:40:03 -08:00
Olivier Fourdan
a1190e7f39 xkb: Make the RT_XKBCLIENT resource private
Currently, the resource in only available to the xkb.c source file.

In preparation for the next commit, to be able to free the resources
from XkbRemoveResourceClient(), make that variable private instead.

This is related to:

CVE-2025-62230, ZDI-CAN-27545

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: Michel Dänzer <mdaenzer@redhat.com>
(cherry picked from commit 99790a2c92)

Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2087>
2026-01-25 10:40:03 -08:00
Alan Coopersmith
224cee1022 Strip trailing whitespace from source files
Performed with: `git ls-files | xargs perl -i -p -e 's{[ \t]+$}{}'`

`git diff -w` & `git diff -b` show no diffs from this change

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2074>
(cherry picked from commit d9389873d6)
2026-01-25 10:40:02 -08:00
Alan Coopersmith
918ec0ab5a xkb: Add tbGetBufferString helper function
Handles common case of allocating & copying string to temporary buffer

(cherry picked from xorg/lib/libxkbfile@8a91517ca6ea77633476595b0eb5b213357c60e5)

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1821>
(cherry picked from commit 42a1f25faf)
2026-01-25 10:40:01 -08:00
Martin Burggraf
8902186636 xkb: correcting mathematical nonsense in XkbGeomFPText
Fixes formatting of negative numbers, so they don't show minus sign
after the decimal point.

(cherry picked from xorg/lib/libxkbfile@d2ec504fec2550f4fd046e801b34317ef4a4bab9)

Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1821>
(cherry picked from commit 7a23010232)
2026-01-25 10:40:01 -08:00
Alan Coopersmith
797455c27a xkb: Convert more sprintf calls to snprintf in xkbtext.c
Based on xorg/lib/libxkbfile@390acfe5bb88cdab509b5eaae4041f265e969d2b

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1821>
(cherry picked from commit 60419d8e4a)
2026-01-25 10:40:01 -08:00
José Expósito
c5146f32f6 xkb: Check that needed is > 0 in XkbResizeKeyActions
Passing a negative value in `needed` to the `XkbResizeKeyActions()`
function can create a `newActs` array of an unespected size.
Check the value and return if it is invalid.

This error has been found by a static analysis tool. This is the report:

    Error: OVERRUN (CWE-119):
    libX11-1.8.7/src/xkb/XKBMAlloc.c:811: cond_const:
      Checking "xkb->server->size_acts == 0" implies that
      "xkb->server->size_acts" is 0 on the true branch.
    libX11-1.8.7/src/xkb/XKBMAlloc.c:811: buffer_alloc:
      "calloc" allocates 8 bytes dictated by parameters
      "(size_t)((xkb->server->size_acts == 0) ? 1 : xkb->server->size_acts)"
      and "8UL".
    libX11-1.8.7/src/xkb/XKBMAlloc.c:811: var_assign:
      Assigning: "newActs" = "calloc((size_t)((xkb->server->size_acts == 0) ? 1 : xkb->server->size_acts), 8UL)".
    libX11-1.8.7/src/xkb/XKBMAlloc.c:815: assignment:
      Assigning: "nActs" = "1".
    libX11-1.8.7/src/xkb/XKBMAlloc.c:829: cond_at_least:
      Checking "nCopy > 0" implies that "nCopy" is at least 1 on the
      true branch.
    libX11-1.8.7/src/xkb/XKBMAlloc.c:830: overrun-buffer-arg:
      Overrunning buffer pointed to by "&newActs[nActs]" of 8 bytes by
      passing it to a function which accesses it at byte offset 15
      using argument "nCopy * 8UL" (which evaluates to 8).
    #  828|
    #  829|           if (nCopy > 0)
    #  830|->             memcpy(&newActs[nActs], XkbKeyActionsPtr(xkb, i),
    #  831|                      nCopy * sizeof(XkbAction));
    #  832|           if (nCopy < nKeyActs)

(cherry picked from xorg/lib/libx11@af1312d2873d2ce49b18708a5029895aed477392)

Signed-off-by: José Expósito <jexposit@redhat.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1821>
(cherry picked from commit 6d33834186)
2026-01-25 10:40:01 -08:00
Alan Coopersmith
e93b15196d xkb: ensure XkbAllocNames sets num_rg to 0 on allocation failure
If there was a previous radio_groups array which we failed to realloc
and freed instead, clear the array size in the XkbNamesRec.

Taken from xorg/lib/libx11@258a8ced681dc1bc50396be7439fce23f9807e2a

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1821>
(cherry picked from commit 09c6f09eb7)
2026-01-25 10:40:01 -08:00
Olivier Fourdan
0fa8f6c48d xkb: Fix buffer overflow in XkbChangeTypesOfKey()
If XkbChangeTypesOfKey() is called with nGroups == 0, it will resize the
key syms to 0 but leave the key actions unchanged.

If later, the same function is called with a non-zero value for nGroups,
this will cause a buffer overflow because the key actions are of the wrong
size.

To avoid the issue, make sure to resize both the key syms and key actions
when nGroups is 0.

CVE-2025-26597, ZDI-CAN-25683

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 0e4ed94952)
2026-01-25 10:40:01 -08:00
Olivier Fourdan
2b17e66b88 xkb: Fix computation of XkbSizeKeySyms
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>
(cherry picked from commit 80d69f0142)
2026-01-25 10:40:01 -08:00
Olivier Fourdan
4252aaedb7 xkb: Fix buffer overflow in XkbVModMaskText()
The code in XkbVModMaskText() allocates a fixed sized buffer on the
stack and copies the virtual mod name.

There's actually two issues in the code that can lead to a buffer
overflow.

First, the bound check mixes pointers and integers using misplaced
parenthesis, defeating the bound check.

But even though, if the check fails, the data is still copied, so the
stack overflow will occur regardless.

Change the logic to skip the copy entirely if the bound check fails.

CVE-2025-26595, ZDI-CAN-25545

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 11fcda8753)
2026-01-25 10:40:00 -08:00
Enrico Weigelt, metux IT consult
3e5eb231bc xkb: drop swapping request length fields
The request struct's length fields aren't used anymore - we have the
client->req_len field instead, which also is bigreq-compatible.

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 9af095e121)
2026-01-25 10:39:58 -08:00
Enrico Weigelt, metux IT consult
9e44d57f9f xkb: fix length checking with bigreq
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>
(cherry picked from commit a623060185)
2026-01-25 10:39:58 -08:00
Julian Orth
d038d2c080 xwayland: Don't run key behaviors and actions
Consider the following keymap:

```xkb
xkb_keymap {
    xkb_keycodes {
        <compose> = 135;
    };
    xkb_symbols {
        key <compose> {
            [ SetGroup(group = +1) ]
        };
    };
};
```

When the user presses the compose key, the following happens:

1. The compositor forwards the key to Xwayland.
2. Xwayland executes the SetGroup action and sets the base_group to 1
   and the effective group to 1.
3. The compositor updates its own state and sends the effective group,
   1, to Xwayland.
4. Xwayland sets the locked group to 1 and the effective group to
   1 + 1 = 2.

This is wrong since pressing compose should set the effective group to 1
but to X applications the effective group appears to be 2.

This commit makes it so that Xwayland completely ignores the key
behaviors and actions of the keymap and only updates the modifier and
group components in response to the wayland modifiers events.

Signed-off-by: Julian Orth <ju.orth@gmail.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1758>
(cherry picked from commit 45c1d22ff6)
2026-01-25 10:39:58 -08:00
Olivier Fourdan
a3171732da xkb: Always use MAP_LENGTH keymap size
Generating the modifier modmap, the helper function generate_modkeymap()
would check the entire range up to the MAP_LENGTH.

However, the given keymap might have less keycodes than MAP_LENGTH, in
which case we would go beyond the size of the modmap, as reported by
ASAN:

==ERROR: AddressSanitizer: heap-buffer-overflow
READ of size 1 at 0x5110001c225b thread T0
    #0 0x5e7369393873 in generate_modkeymap ../dix/inpututils.c:309
    #1 0x5e736930dcce in ProcGetModifierMapping ../dix/devices.c:1794
    #2 0x5e7369336489 in Dispatch ../dix/dispatch.c:550
    #3 0x5e736934407d in dix_main ../dix/main.c:275
    #5 0x7e46d47b2ecb in __libc_start_main
    #6 0x5e73691be324 in _start (xserver/build/hw/xwayland/Xwayland)

Address is located 0 bytes after 219-byte region
allocated by thread T0 here:
    #0 0x7e46d4cfc542 in realloc
    #1 0x5e73695aa90e in _XkbCopyClientMap ../xkb/xkbUtils.c:1142
    #2 0x5e73695aa90e in XkbCopyKeymap ../xkb/xkbUtils.c:1966
    #3 0x5e73695b1b2f in XkbDeviceApplyKeymap ../xkb/xkbUtils.c:2023
    #4 0x5e73691c6c18 in keyboard_handle_keymap ../hw/xwayland/xwayland-input.c:1194

As MAP_LENGTH is used in various code paths where the max keycode might
not be easily available, best is to always use MAP_LENGTH to allocate the
keymaps so that the code never run past the buffer size.

If the max key code is smaller than the MAP_LENGTH limit, fill-in the gap
with zeros.

That also simplifies the code slightly as we do not constantly need to
reallocate the keymap to adjust to the max key code size.

Closes: https://gitlab.freedesktop.org/xorg/xserver/-/issues/1780
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1762>
(cherry picked from commit 92bcebfd7e)
2026-01-25 10:39:58 -08:00
Matthieu Herrb
4cd8533210 xkb: Fix buffer overflow in _XkbSetCompatMap()
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>
(cherry picked from commit 85b7765714)
2026-01-25 10:39:58 -08:00
Enrico Weigelt, metux IT consult
34f3752ab8 dix: unexport Ones()
It's not used by any module/driver, so no need to keep it exported.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1695>
(cherry picked from commit 1642adec3b)
2026-01-25 10:39:57 -08:00
Enrico Weigelt, metux IT consult
ded22f6af9 xkb: drop unused variable extDevReason
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>
(cherry picked from commit 9432106b30)
2026-01-25 10:39:57 -08:00
Enrico Weigelt, metux IT consult
2a7e2bcb77 xkb: xkbInit: fix char signess mismatch
On NetBSD gives warning:

../xkb/xkbInit.c: In function ‘XkbProcessArguments’:
../xkb/xkbInit.c:778:57: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  778 |             if (((i + 1) < argc) && (isdigit(argv[i + 1][0]))) {
      |                                                         ^
../xkb/xkbInit.c:782:61: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  782 |                 if (((i + 1) < argc) && (isdigit(argv[i + 1][0]))) {
      |                                                             ^
../xkb/xkbInit.c:792:61: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  792 |                 if (((i + 1) < argc) && (isdigit(argv[i + 1][0]))) {
      |                                                             ^
../xkb/xkbInit.c:799:61: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  799 |                 if (((i + 1) < argc) && (isdigit(argv[i + 1][0]))) {
      |                                                             ^

Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1455>
(cherry picked from commit e79dfb87e9)
2026-01-25 10:39:57 -08:00
Enrico Weigelt, metux IT consult
c34a791188 xkb: xkbtext: fix char signess mismatch
On NetBSD gives warning:

In file included from /usr/include/ctype.h:100,
                 from ../xkb/xkbtext.c:32:
../xkb/xkbtext.c: In function ‘XkbAtomText’:
../xkb/xkbtext.c:94:44: warning: array subscript has type ‘char’ [-Wchar-subscripts]
   94 |             if ((tmp == rtrn) && (!isalpha(*tmp)))
      |                                            ^
../xkb/xkbtext.c:96:31: warning: array subscript has type ‘char’ [-Wchar-subscripts]
   96 |             else if (!isalnum(*tmp))
      |                               ^
../xkb/xkbtext.c: In function ‘XkbIMWhichStateMaskText’:
../xkb/xkbtext.c:470:43: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  470 |                 buf[len + 9] = toupper(buf[len + 9]);
      |                                           ^
../xkb/xkbtext.c: In function ‘XkbControlsMaskText’:
../xkb/xkbtext.c:532:43: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  532 |                 buf[len + 3] = toupper(buf[len + 3]);
      |                                           ^
../xkb/xkbtext.c: In function ‘XkbStringText’:
../xkb/xkbtext.c:563:22: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  563 |         if (!isprint(*in)) {
      |                      ^
../xkb/xkbtext.c:584:21: warning: array subscript has type ‘char’ [-Wchar-subscripts]
  584 |         if (isprint(*in))
      |                     ^

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1455>
(cherry picked from commit 02be87b880)
2026-01-25 10:39:57 -08:00
Enrico Weigelt, metux IT consult
c1eae1f117 treewide: replace xnfstrdup() calls by XNFstrdup()
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 dec57e5796)
2026-01-25 10:39:55 -08:00
Enrico Weigelt, metux IT consult
144f197282 treewide: replace strdup() calls to Xstrdup()
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 9ec31d1a88)
2026-01-25 10:39:55 -08:00
Enrico Weigelt, metux IT consult
d9f8206afb treewide: replace xnfalloc() calls to XNFalloc()
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.

Fixes: ded6147bfb
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 c55ddd072b)
2026-01-25 10:39:55 -08:00
Enrico Weigelt, metux IT consult
6d7eaaf6e1 xkb: ProcXkbGetGeometry(): fix memleak
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>
(cherry picked from commit b2198df55a)
2026-01-25 10:39:55 -08:00
Enrico Weigelt, metux IT consult
dd0dcbe99d xace: typesafe hook function for XACE_SERVER_ACCESS
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)
2026-01-25 10:39:54 -08:00
Enrico Weigelt, metux IT consult
e4465f2cdb xace: typesafe hook function for XACE_DEVICE_ACCESS
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>
(cherry picked from commit 9524ffee89)
2026-01-25 10:39:54 -08:00
Dr. David Alan Gilbert
1365d82f13 xkb: deadcode cleanup
The last use of struct '_SrvXkmInfo' was removed in
commit fbd7768946 ("XKB: Ditch XkbFileInfo").
Remove it.

The define MAX_TOC hasn't been used in this file since sometime
in the mid 90's; it's unused in version '1997/05/20 11:42:06'
but in '1.8 94/05/16 10:49:53' it's used in the definition
of _SrvXkmInfo.
Remove it.

Build tested.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1558>
(cherry picked from commit d94bff7880)
2026-01-25 10:39:53 -08:00
Enrico Weigelt, metux IT consult
a5ae327f5d xkb: make XkbInternAtom() static
It's only used in the same .c file, so make it static.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1506>
(cherry picked from commit 8a2590e5d3)
2026-01-25 10:39:53 -08:00
Enrico Weigelt, metux IT consult
09a1b2851b xkb: move *_TIMER defines into xkbAccessX.c
These are only used in this file (and also not any external driver),
so no need to have them in a public header file.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1459>
(cherry picked from commit feb5c785fc)
2026-01-25 10:39:52 -08:00
Enrico Weigelt, metux IT consult
ceceb36251 xkb: drop ununsed XkbNameMatchesPattern()
Not used anywhere, also not in drivers, so we can drop it.
Probably never been used, just added accidentially back in 2008.

Fixes: 68bd7ac193
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1477>
(cherry picked from commit beb073813e)
2026-01-19 12:32:25 -08:00
Enrico Weigelt, metux IT consult
346a4d0277 xkb: drop never used XkmProbe()
This function was (accidentally ?) added back in 2008, but never used.

Fixes: 68bd7ac193
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1472>
(cherry picked from commit fdea36708c)
2026-01-19 12:32:24 -08:00
Enrico Weigelt, metux IT consult
d81bc72255 xkb: make XkbUpdateKeyTypesFromCore() static
This function is only used inside the same .c file where it's defined,
no outside users, also not in drivers. Thus no need to keep it exported.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1468>
(cherry picked from commit 95faea8880)
2026-01-19 12:32:24 -08:00
Enrico Weigelt, metux IT consult
977bed5187 xkb: drop duplicate _X_EXPORT from .c source
It's already defined in input.h, and that's where it belongs.
(we see from the header, which symbols belong to the module api)

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1274>
(cherry picked from commit 86ea30733f)
2026-01-19 12:32:19 -08:00