4.19-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Torokhov dmitry.torokhov@gmail.com
commit f39f8688888ae74fa8deae2d01289b69b4727394 upstream.
synaptics_detect() does not check whether sending commands to the device succeeds and instead relies on getting unique data from the device. Let's make sure we seed entire buffer with zeroes to make sure we will not use garbage on stack that just happen to be 0x47.
Reported-by: syzbot+13cb3b01d0784e4ffc3f@syzkaller.appspotmail.com Reviewed-by: Benjamin Tissoires benjamin.tissoires@redhat.com Reviewed-by: Peter Hutterer peter.hutterer@who-t.net Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/input/mouse/synaptics.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
--- a/drivers/input/mouse/synaptics.c +++ b/drivers/input/mouse/synaptics.c @@ -99,9 +99,7 @@ static int synaptics_mode_cmd(struct psm int synaptics_detect(struct psmouse *psmouse, bool set_properties) { struct ps2dev *ps2dev = &psmouse->ps2dev; - u8 param[4]; - - param[0] = 0; + u8 param[4] = { 0 };
ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES); ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);