Hi All,
David Airlie and Peter Hutterer of Red Hat found an information
disclosure flaw was found in the way X.org X11 server used to register
new hot-plug devices, when X.org X11 server was instructed (for that
particular moment) not to receive input devices events. Formerly when
registering new input device, X.org X11 server simultaneously enabled
retrieval of input from the particular device (regardless of the
setting).
A local unsuspecting user, relying on the X.org X11 server disable
input feature it to properly prohibit acquiring of events from this
newly added hot-plug device, could supply a sensitive information that,
due the above bug, would become available to the physically proximate
attackers.
Upstream patch:
http://cgit.freedesktop.org/xorg/xserver/commit/?id=6ca03b9161d33b1d2b55a3a1a913cf88deb2343f
Red Hat Bugzilla:
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2013-1940
This issue has been assigned CVE-2013-1940
--- a/hw/xfree86/os-support/shared/posix_tty.c
+++ b/hw/xfree86/os-support/shared/posix_tty.c
@@ -421,7 +421,8 @@ xf86FlushInput(int fd)
{
fd_set fds;
struct timeval timeout;
- char c[4];
+ /* this needs to be big enough to flush an evdev event. */
+ char c[256];
DebugF("FlushingSerial\n");
if (tcflush(fd, TCIFLUSH) == 0)