diff --git a/drivers/net/wireless/prism54/isl_ioctl.c b/drivers/net/wireless/prism54/isl_ioctl.c
index 236e37526d07..2e656bb7e14e 100644
--- a/drivers/net/wireless/prism54/isl_ioctl.c
+++ b/drivers/net/wireless/prism54/isl_ioctl.c
@@ -2067,7 +2067,7 @@ send_simple_event(islpci_private *priv, const char *str)
 	memptr = kmalloc(IW_CUSTOM_MAX, GFP_KERNEL);
 	if (!memptr)
 		return;
-	BUG_ON(n > IW_CUSTOM_MAX);
+	BUG_ON(n >= IW_CUSTOM_MAX);
 	wrqu.data.pointer = memptr;
 	wrqu.data.length = n;
 	strcpy(memptr, str);