Fixes the following security issues:
1) CVE-2023-6377: X.Org server: Out-of-bounds memory write in XKB button actions
A device has XKB button actions for each button on the device. When a
logical device switch happens (e.g. moving from a touchpad to a mouse), the
server re-calculates the information available on the respective master
device (typically the Virtual Core Pointer). This re-calculation only
allocated enough memory for a single XKB action rather instead of enough for
the newly active physical device's number of button. As a result, querying
or changing the XKB button actions results in out-of-bounds memory reads and
writes.
This may lead to local privilege escalation if the server is run as root or
remote code execution (e.g. x11 over ssh).
2) CVE-2023-6478: X.Org server: Out-of-bounds memory read in
RRChangeOutputProperty and RRChangeProviderProperty
This fixes an OOB read and the resulting information disclosure.
Length calculation for the request was clipped to a 32-bit integer. With
the correct stuff->nUnits value the expected request size was truncated,
passing the REQUEST_FIXED_SIZE check.
The server then proceeded with reading at least stuff->nUnits bytes
(depending on stuff->format) from the request and stuffing whatever it finds
into the property. In the process it would also allocate at least
stuff->nUnits bytes, i.e. 4GB.
See also CVE-2022-46344 where this issue was fixed for other requests.
For more details, see the advisory:
https://lists.x.org/archives/xorg-announce/2023-December/003435.html
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
