Commit a9ace75f6492304a59ae7b192b05f241e2694764
2018-08-18T14:28:15
x11: fix undefined behavior when copying the coordinates of ptr movements actions Left shift of a negative integer. For some reason the protocol representation here got really botched (in the spec it is just a nice and simple INT16). Signed-off-by: Ran Benita <ran234@gmail.com>
diff --git a/meson.build b/meson.build
index 9effe29..87193dd 100644
--- a/meson.build
+++ b/meson.build
@@ -31,6 +31,7 @@ foreach cflag: [
'-Wdate-time',
'-Wwrite-strings',
'-Wno-documentation-deprecated-sync',
+ '-fsanitize-undefined-trap-on-error',
]
if cc.has_argument(cflag)
add_project_arguments(cflag, language: 'c')
diff --git a/src/x11/keymap.c b/src/x11/keymap.c
index 1642011..701b614 100644
--- a/src/x11/keymap.c
+++ b/src/x11/keymap.c
@@ -218,8 +218,8 @@ translate_action(union xkb_action *action, const xcb_xkb_action_t *wire)
case XCB_XKB_SA_TYPE_MOVE_PTR:
action->type = ACTION_TYPE_PTR_MOVE;
- action->ptr.x = (wire->moveptr.xLow | (wire->moveptr.xHigh << 8));
- action->ptr.y = (wire->moveptr.yLow | (wire->moveptr.yHigh << 8));
+ action->ptr.x = (int16_t) (wire->moveptr.xLow | ((uint16_t) wire->moveptr.xHigh << 8));
+ action->ptr.y = (int16_t) (wire->moveptr.yLow | ((uint16_t) wire->moveptr.yHigh << 8));
if (!(wire->moveptr.flags & XCB_XKB_SA_MOVE_PTR_FLAG_NO_ACCELERATION))
action->ptr.flags |= ACTION_ACCEL;