Always check for EBUSY when the return value of ic_set_key() is tested.

Fixes urtwn(4) repeated DEAUTH and subsequent loss/restoration of link.
It was a great dhclient(4) stress test. Note that urtwn(4) is the first
and so far only device whose *_set_key() function returns EBUSY.

Debugging hints and ok stsp@

3 files changed, 44 insertions, 11 deletions

diff --git a/sys/net80211/ieee80211_ioctl.c b/sys/net80211/ieee80211_ioctl.c
index a458e3af59a..e3da39394d2 100644
--- a/sys/net80211/ieee80211_ioctl.c
+++ b/sys/net80211/ieee80211_ioctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_ioctl.c,v 1.79 2020/01/15 09:34:27 phessler Exp $	*/
+/*	$OpenBSD: ieee80211_ioctl.c,v 1.80 2020/11/19 20:03:33 krw Exp $	*/
 /*	$NetBSD: ieee80211_ioctl.c,v 1.15 2004/05/06 02:58:16 dyoung Exp $	*/
 
 /*-
@@ -246,8 +246,14 @@ ieee80211_ioctl_setnwkeys(struct ieee80211com *ic,
 		error = copyin(nwkey->i_key[i].i_keydat, k->k_key, k->k_len);
 		if (error != 0)
 			return error;
-		if ((error = (*ic->ic_set_key)(ic, NULL, k)) != 0)
+		error = (*ic->ic_set_key)(ic, NULL, k);
+		switch (error) {
+		case 0:
+		case EBUSY:
+			break;
+		default:
 			return error;
+		}
 	}
 
 	ic->ic_def_txkey = nwkey->i_defkid - 1;
diff --git a/sys/net80211/ieee80211_pae_input.c b/sys/net80211/ieee80211_pae_input.c
index 06d8767ab69..daf550f591f 100644
--- a/sys/net80211/ieee80211_pae_input.c
+++ b/sys/net80211/ieee80211_pae_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_pae_input.c,v 1.36 2020/11/12 13:31:19 krw Exp $	*/
+/*	$OpenBSD: ieee80211_pae_input.c,v 1.37 2020/11/19 20:03:33 krw Exp $	*/
 
 /*-
  * Copyright (c) 2007,2008 Damien Bergamini <damien.bergamini@free.fr>
@@ -724,7 +724,11 @@ ieee80211_recv_4way_msg4(struct ieee80211com *ic,
 		k->k_len = ieee80211_cipher_keylen(k->k_cipher);
 		memcpy(k->k_key, ni->ni_ptk.tk, k->k_len);
 		/* install the PTK */
-		if ((*ic->ic_set_key)(ic, ni, k) != 0) {
+		switch ((*ic->ic_set_key)(ic, ni, k)) {
+		case 0:
+		case EBUSY:
+			break;
+		default:
 			IEEE80211_SEND_MGMT(ic, ni,
 			    IEEE80211_FC0_SUBTYPE_DEAUTH,
 			    IEEE80211_REASON_ASSOC_TOOMANY);
@@ -894,7 +898,11 @@ ieee80211_recv_rsn_group_msg1(struct ieee80211com *ic,
 		k->k_len = keylen;
 		memcpy(k->k_key, &gtk[8], k->k_len);
 		/* install the GTK */
-		if ((*ic->ic_set_key)(ic, ni, k) != 0) {
+		switch ((*ic->ic_set_key)(ic, ni, k)) {
+		case 0:
+		case EBUSY:
+			break;
+		default:
 			reason = IEEE80211_REASON_AUTH_LEAVE;
 			goto deauth;
 		}
@@ -922,7 +930,11 @@ ieee80211_recv_rsn_group_msg1(struct ieee80211com *ic,
 			k->k_len = 16;
 			memcpy(k->k_key, &igtk[14], k->k_len);
 			/* install the IGTK */
-			if ((*ic->ic_set_key)(ic, ni, k) != 0) {
+			switch ((*ic->ic_set_key)(ic, ni, k)) {
+			case 0:
+			case EBUSY:
+				break;
+			default:
 				reason = IEEE80211_REASON_AUTH_LEAVE;
 				goto deauth;
 			}
@@ -1026,7 +1038,11 @@ ieee80211_recv_wpa_group_msg1(struct ieee80211com *ic,
 		k->k_len = keylen;
 		memcpy(k->k_key, gtk, k->k_len);
 		/* install the GTK */
-		if ((*ic->ic_set_key)(ic, ni, k) != 0) {
+		switch ((*ic->ic_set_key)(ic, ni, k)) {
+		case 0:
+		case EBUSY:
+			break;
+		default:
 			IEEE80211_SEND_MGMT(ic, ni, IEEE80211_FC0_SUBTYPE_DEAUTH,
 			    IEEE80211_REASON_AUTH_LEAVE);
 			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
diff --git a/sys/net80211/ieee80211_proto.c b/sys/net80211/ieee80211_proto.c
index 2027b67c2ff..5170329026a 100644
--- a/sys/net80211/ieee80211_proto.c
+++ b/sys/net80211/ieee80211_proto.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_proto.c,v 1.98 2020/05/29 07:37:51 stsp Exp $	*/
+/*	$OpenBSD: ieee80211_proto.c,v 1.99 2020/11/19 20:03:33 krw Exp $	*/
 /*	$NetBSD: ieee80211_proto.c,v 1.8 2004/04/30 23:58:20 dyoung Exp $	*/
 
 /*-
@@ -479,15 +479,26 @@ ieee80211_setkeysdone(struct ieee80211com *ic)
 
 	/* install GTK */
 	kid = (ic->ic_def_txkey == 1) ? 2 : 1;
-	if ((*ic->ic_set_key)(ic, ic->ic_bss, &ic->ic_nw_keys[kid]) == 0)
+	switch ((*ic->ic_set_key)(ic, ic->ic_bss, &ic->ic_nw_keys[kid])) {
+	case 0:
+	case EBUSY:
 		ic->ic_def_txkey = kid;
+		break;
+	default:
+		break;
+	}
 
 	if (ic->ic_caps & IEEE80211_C_MFP) {
 		/* install IGTK */
 		kid = (ic->ic_igtk_kid == 4) ? 5 : 4;
-		if ((*ic->ic_set_key)(ic, ic->ic_bss,
-		    &ic->ic_nw_keys[kid]) == 0)
+		switch ((*ic->ic_set_key)(ic, ic->ic_bss, &ic->ic_nw_keys[kid])) {
+		case 0:
+		case EBUSY:
 			ic->ic_igtk_kid = kid;
+			break;
+		default:
+			break;
+		}
 	}
 }