From 34412ba28232e8b3b4955a4bbe53c9df4c7b2d1a Mon Sep 17 00:00:00 2001 From: Pali Rohár Date: Fri, 9 Jan 2015 12:48:58 -0800 Subject: Input: alps - add sanity checks for non DualPoint devices MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Make sure that driver does not process bogus packets as trackstick data when there is no trackstick present and emit warnings in dmesg so potential issues with trackstick handling will be visible for debugging. Signed-off-by: Pali Rohár Signed-off-by: Dmitry Torokhov --- drivers/input/mouse/alps.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) (limited to 'drivers/input/mouse') diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c index 4d7c4ccdaa8a..dd2fd397466a 100644 --- a/drivers/input/mouse/alps.c +++ b/drivers/input/mouse/alps.c @@ -475,6 +475,13 @@ static void alps_process_trackstick_packet_v3(struct psmouse *psmouse) struct input_dev *dev = priv->dev2; int x, y, z, left, right, middle; + /* It should be a DualPoint when received trackstick packet */ + if (!(priv->flags & ALPS_DUALPOINT)) { + psmouse_warn(psmouse, + "Rejected trackstick packet from non DualPoint device"); + return; + } + /* Sanity check packet */ if (!(packet[0] & 0x40)) { psmouse_dbg(psmouse, "Bad trackstick packet, discarding\n"); @@ -699,7 +706,8 @@ static void alps_process_touchpad_packet_v3_v5(struct psmouse *psmouse) alps_report_semi_mt_data(psmouse, fingers); - if (!(priv->quirks & ALPS_QUIRK_TRACKSTICK_BUTTONS)) { + if ((priv->flags & ALPS_DUALPOINT) && + !(priv->quirks & ALPS_QUIRK_TRACKSTICK_BUTTONS)) { input_report_key(dev2, BTN_LEFT, f->ts_left); input_report_key(dev2, BTN_RIGHT, f->ts_right); input_report_key(dev2, BTN_MIDDLE, f->ts_middle); @@ -743,8 +751,11 @@ static void alps_process_packet_v6(struct psmouse *psmouse) */ if (packet[5] == 0x7F) { /* It should be a DualPoint when received Trackpoint packet */ - if (!(priv->flags & ALPS_DUALPOINT)) + if (!(priv->flags & ALPS_DUALPOINT)) { + psmouse_warn(psmouse, + "Rejected trackstick packet from non DualPoint device"); return; + } /* Trackpoint packet */ x = packet[1] | ((packet[3] & 0x20) << 2); @@ -1026,6 +1037,13 @@ static void alps_process_trackstick_packet_v7(struct psmouse *psmouse) struct input_dev *dev2 = priv->dev2; int x, y, z, left, right, middle; + /* It should be a DualPoint when received trackstick packet */ + if (!(priv->flags & ALPS_DUALPOINT)) { + psmouse_warn(psmouse, + "Rejected trackstick packet from non DualPoint device"); + return; + } + /* * b7 b6 b5 b4 b3 b2 b1 b0 * Byte0 0 1 0 0 1 0 0 0 -- cgit v1.2.3-59-g8ed1b