Changing XRandR provider properties if the driver has set no provider
function such as the modesetting driver will cause a NULL pointer
dereference and a crash of the Xorg server.
Related to CVE-2025-49180
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: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
A client might send a request causing an integer overflow when computing
the total size to allocate in RRChangeProviderProperty().
To avoid the issue, check that total length in bytes won't exceed the
maximum integer value.
CVE-2025-49180
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: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
The RecordSanityCheckRegisterClients() checks for the request length,
but does not check for integer overflow.
A client might send a very large value for either the number of clients
or the number of protocol ranges that will cause an integer overflow in
the request length computation, defeating the check for request length.
To avoid the issue, explicitly check the number of clients against the
limit of clients (which is much lower than an maximum integer value) and
the number of protocol ranges (multiplied by the record length) do not
exceed the maximum integer value.
This way, we ensure that the final computation for the request length
will not overflow the maximum integer limit.
CVE-2025-49179
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: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
When reading requests from the clients, the input buffer might be shared
and used between different clients.
If a given client sends a full request with non-zero bytes to ignore,
the bytes to ignore may still be non-zero even though the request is
full, in which case the buffer could be shared with another client who's
request will not be processed because of those bytes to ignore, leading
to a possible hang of the other client request.
To avoid the issue, make sure we have zero bytes to ignore left in the
input request when sharing the input buffer with another client.
CVE-2025-49178
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: Peter Hutterer <peter.hutterer@who-t.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
The handler of XFixesSetClientDisconnectMode does not check the client
request length.
A client could send a shorter request and read data from a former
request.
Fix the issue by checking the request size matches.
CVE-2025-49177
This issue was discovered by Nils Emmerich <nemmerich@ernw.de> and
reported by Julian Suleder via ERNW Vulnerability Disclosure.
Fixes: e167299f6 - xfixes: Add ClientDisconnectMode
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/2024>
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>
Animated cursors use a series of cursors that the client can set.
By default, the Xserver assumes at least one cursor is specified
while a client may actually pass no cursor at all.
That causes an out-of-bound read creating the animated cursor and a
crash of the Xserver:
| Invalid read of size 8
| at 0x5323F4: AnimCursorCreate (animcur.c:325)
| by 0x52D4C5: ProcRenderCreateAnimCursor (render.c:1817)
| by 0x52DC80: ProcRenderDispatch (render.c:1999)
| by 0x4A1E9D: Dispatch (dispatch.c:560)
| by 0x4B0169: dix_main (main.c:284)
| by 0x4287F5: main (stubmain.c:34)
| Address 0x59aa010 is 0 bytes after a block of size 0 alloc'd
| at 0x48468D3: reallocarray (vg_replace_malloc.c:1803)
| by 0x52D3DA: ProcRenderCreateAnimCursor (render.c:1802)
| by 0x52DC80: ProcRenderDispatch (render.c:1999)
| by 0x4A1E9D: Dispatch (dispatch.c:560)
| by 0x4B0169: dix_main (main.c:284)
| by 0x4287F5: main (stubmain.c:34)
|
| Invalid read of size 2
| at 0x5323F7: AnimCursorCreate (animcur.c:325)
| by 0x52D4C5: ProcRenderCreateAnimCursor (render.c:1817)
| by 0x52DC80: ProcRenderDispatch (render.c:1999)
| by 0x4A1E9D: Dispatch (dispatch.c:560)
| by 0x4B0169: dix_main (main.c:284)
| by 0x4287F5: main (stubmain.c:34)
| Address 0x8 is not stack'd, malloc'd or (recently) free'd
To avoid the issue, check the number of cursors specified and return a
BadValue error in both the proc handler (early) and the animated cursor
creation (as this is a public function) if there is 0 or less cursor.
CVE-2025-49175
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: José Expósito <jexposit@redhat.com>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2024>
Alan Coopersmith
Olivier Fourdan
Marge Bot