diff options
| author | Peter Hutterer <peter.hutterer@who-t.net> | 2012-08-30 16:38:38 +1000 |
|---|---|---|
| committer | Peter Hutterer <peter.hutterer@who-t.net> | 2012-08-31 07:49:27 +1000 |
| commit | eae444eb1a85d2401501d29f9a6c654c046f806b (patch) | |
| tree | 753aa1db34d8660e9d9accaaea75a19728b869c5 /src | |
| parent | d5ff9d8b0b186cf39695df84a10984eac559b746 (diff) | |
Reset num_active_touches on DeviceOff (#52496)
When disabling the device, reset num_active_touches to zero. Otherwise,
num_active_touches stays at the value it was on DeviceOff(). Future touches
add to that value until the index may go past priv->open_slots[].
That causes spurious memory corruption on touch ends.
And as of 55fc42e7c9b4948cadd4f98ef7b6a3b12e268e3e we ignore pre-existing
touches anyway.
Test-case:
- place num_touches fingers on the touchpad
- xinput disable <device>
- lift fingers
- xinput enable <device>
- place finger on device, num_active_touches is now (num_touches + 1)
X.Org Bug 52496 <http://bugs.freedesktop.org/show_bug.cgi?id=52496>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Chase Douglas <chase.douglas@canonical.com>
(cherry picked from commit a245d42f53096b1ae81e6702729f97ca508e5b5b)
Conflicts:
src/synaptics.c
Diffstat (limited to 'src')
| -rw-r--r-- | src/synaptics.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/src/synaptics.c b/src/synaptics.c index cd9f936..a28e984 100644 --- a/src/synaptics.c +++ b/src/synaptics.c @@ -1154,6 +1154,7 @@ SynapticsReset(SynapticsPrivate * priv) priv->prev_z = 0; priv->prevFingers = 0; #ifdef HAVE_MULTITOUCH + priv->num_active_touches = 0; memset(priv->open_slots, 0, priv->num_slots * sizeof(int)); #endif } @@ -3118,6 +3119,7 @@ UpdateTouchState(InputInfoPtr pInfo, struct SynapticsHwState *hw) if (hw->slot_state[i] == SLOTSTATE_OPEN) { priv->open_slots[priv->num_active_touches] = i; priv->num_active_touches++; + BUG_WARN(priv->num_active_touches > priv->num_slots); } else if (hw->slot_state[i] == SLOTSTATE_CLOSE) { Bool found = FALSE; |