iwlwifi: fix TX tracer

The TX tracing code copies with the wrong length,
which will typically copy too little data. Fix
this by using the correct length variable.

Cc: stable@kernel.org [2.6.32+]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-devtrace.h

@@ -193,7 +193,7 @@ TRACE_EVENT(iwlwifi_dev_tx,
 		__entry->framelen = buf0_len + buf1_len;
 		memcpy(__get_dynamic_array(tfd), tfd, tfdlen);
 		memcpy(__get_dynamic_array(buf0), buf0, buf0_len);
-		memcpy(__get_dynamic_array(buf1), buf1, buf0_len);
+		memcpy(__get_dynamic_array(buf1), buf1, buf1_len);
 	),
 	TP_printk("[%p] TX %.2x (%zu bytes)",
 		  __entry->priv,