From 6ccee710bd60fe9d0bc058cf7f7dbe960b3891dd Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Wed, 19 Feb 2020 13:18:48 +1000 Subject: [PATCH] Ignore slot sync for slots > 256 Clang doesn't support variable length arrays inside a struct so we could either make our life complicated or just assume no-one is using more than 256 slots and hard-code that. Let's go for the easy solution until someone notices. Signed-off-by: Peter Hutterer --- libevdev/libevdev.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/libevdev/libevdev.c b/libevdev/libevdev.c index 98645bb..bd6fc96 100644 --- a/libevdev/libevdev.c +++ b/libevdev/libevdev.c @@ -677,16 +677,15 @@ static int sync_mt_state(struct libevdev *dev, struct slot_change_state changes_out[dev->num_slots]) { +#define MAX_SLOTS 256 int rc; - struct slot_change_state changes[dev->num_slots]; - - memset(changes, 0, sizeof(changes)); + struct slot_change_state changes[MAX_SLOTS] = {0}; for (int axis = ABS_MT_MIN; axis <= ABS_MT_MAX; axis++) { /* EVIOCGMTSLOTS required format */ struct mt_sync_state { uint32_t code; - int32_t val[dev->num_slots]; + int32_t val[MAX_SLOTS]; } mt_state; if (axis == ABS_MT_SLOT || @@ -698,7 +697,7 @@ sync_mt_state(struct libevdev *dev, if (rc < 0) goto out; - for (int slot = 0; slot < dev->num_slots; slot++) { + for (int slot = 0; slot < min(MAX_SLOTS, dev->num_slots); slot++) { int val_before = *slot_value(dev, slot, axis), val_after = mt_state.val[slot]; @@ -729,7 +728,7 @@ sync_mt_state(struct libevdev *dev, } } - memcpy(changes_out, changes, sizeof(changes)); + memcpy(changes_out, changes, sizeof(*changes) * dev->num_slots); out: return rc; } -- 2.34.1