diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 62047e93e217..65fc674e27cc 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2194,6 +2194,16 @@ ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 	return NULL;
 }
 
+static bool requires_sequential_pn(struct ieee80211_rx_data *rx, __le16 fc)
+{
+	return rx->key &&
+		(rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
+		 rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
+		 rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
+		 rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
+		ieee80211_has_protected(fc);
+}
+
 static ieee80211_rx_result debug_noinline
 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 {
@@ -2238,12 +2248,7 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 		/* This is the first fragment of a new frame. */
 		entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 						 rx->seqno_idx, &(rx->skb));
-		if (rx->key &&
-		    (rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
-		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
-		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
-		     rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
-		    ieee80211_has_protected(fc)) {
+		if (requires_sequential_pn(rx, fc)) {
 			int queue = rx->security_idx;
 
 			/* Store CCMP/GCMP PN so that we can verify that the
@@ -2285,11 +2290,7 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 		u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
 		int queue;
 
-		if (!rx->key ||
-		    (rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP &&
-		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP_256 &&
-		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP &&
-		     rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP_256))
+		if (!requires_sequential_pn(rx, fc))
 			return RX_DROP_UNUSABLE;
 		memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
 		for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {