diff --git a/src/shell.c b/src/shell.c
index 9c844b5f..2001133e 100644
--- a/src/shell.c
+++ b/src/shell.c
@@ -447,7 +447,7 @@ ping_handler(struct weston_surface *surface, uint32_t serial)
 		return;
 
 	if (!shsurf->ping_timer) {
-		shsurf->ping_timer = malloc(sizeof shsurf->ping_timer);
+		shsurf->ping_timer = malloc(sizeof *shsurf->ping_timer);
 		if (!shsurf->ping_timer)
 			return;