ANDROID: net: wireless: bcmdhd: Verify SSID lengthMXC89HMXC89F

    Ensure SSID length is correct before memcpy

    Bug=26571522
    Bug=27240072

Change-Id: Ia650ec88268d0efc3ae33f3435c3e6ee91e6a642
Signed-off-by: Jerry Lee <jerrylee@broadcom.com>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/337262

1 files changed, 53 insertions, 27 deletions

diff --git a/drivers/net/wireless/bcmdhd/wl_cfg80211.c b/drivers/net/wireless/bcmdhd/wl_cfg80211.c
index 0e44bc10016b..96cceacdb887 100644
--- a/drivers/net/wireless/bcmdhd/wl_cfg80211.c
+++ b/drivers/net/wireless/bcmdhd/wl_cfg80211.c
@@ -2036,15 +2036,17 @@ static void wl_scan_prep(struct bcm_cfg80211 *cfg, struct wl_scan_params *params
 		WL_SCAN(("Scanning all channels\n"));
 	}
 	n_channels = j;
+
 	/* Copy ssid array if applicable */
 	WL_SCAN(("### List of SSIDs to scan ###\n"));
 	if (n_ssids > 0) {
 		offset = offsetof(wl_scan_params_t, channel_list) + n_channels * sizeof(u16);
 		offset = roundup(offset, sizeof(u32));
 		ptr = (char*)params + offset;
+
 		for (i = 0; i < n_ssids; i++) {
 			memset(&ssid, 0, sizeof(wlc_ssid_t));
-			ssid.SSID_len = request->ssids[i].ssid_len;
+			ssid.SSID_len = MIN((int)request->ssids[i].ssid_len, DOT11_MAX_SSID_LEN);
 			memcpy(ssid.SSID, request->ssids[i].ssid, ssid.SSID_len);
 			if (!ssid.SSID_len)
 				WL_SCAN(("%d: Broadcast scan\n", i));
@@ -3216,7 +3218,8 @@ wl_cfg80211_join_ibss(struct wiphy *wiphy, struct net_device *dev,
 	WL_TRACE(("In\n"));
 	RETURN_EIO_IF_NOT_UP(cfg);
 	WL_INFORM(("JOIN BSSID:" MACDBG "\n", MAC2STRDBG(params->bssid)));
-	if (!params->ssid || params->ssid_len <= 0) {
+
+	if (!params->ssid || params->ssid_len <= 0 || params->ssid_len > DOT11_MAX_SSID_LEN) {
 		WL_ERR(("Invalid parameter\n"));
 		return -EINVAL;
 	}
@@ -6506,16 +6509,16 @@ static s32 wl_cfg80211_bcn_set_params(
 	}
 
 	if ((info->ssid) && (info->ssid_len > 0) &&
-		(info->ssid_len <= 32)) {
+		(info->ssid_len <= DOT11_MAX_SSID_LEN)) {
 		WL_DBG(("SSID (%s) len:%zd \n", info->ssid, info->ssid_len));
 		if (dev_role == NL80211_IFTYPE_AP) {
 			/* Store the hostapd SSID */
-			memset(cfg->hostapd_ssid.SSID, 0x00, 32);
+			memset(cfg->hostapd_ssid.SSID, 0x00, DOT11_MAX_SSID_LEN);
 			memcpy(cfg->hostapd_ssid.SSID, info->ssid, info->ssid_len);
 			cfg->hostapd_ssid.SSID_len = info->ssid_len;
 		} else {
-				/* P2P GO */
-			memset(cfg->p2p->ssid.SSID, 0x00, 32);
+			/* P2P GO */
+			memset(cfg->p2p->ssid.SSID, 0x00, DOT11_MAX_SSID_LEN);
 			memcpy(cfg->p2p->ssid.SSID, info->ssid, info->ssid_len);
 			cfg->p2p->ssid.SSID_len = info->ssid_len;
 		}
@@ -6654,11 +6657,14 @@ wl_cfg80211_bcn_bringup_ap(
 		}
 
 		memset(&join_params, 0, sizeof(join_params));
+
 		/* join parameters starts with ssid */
 		join_params_size = sizeof(join_params.ssid);
+		join_params.ssid.SSID_len = MIN(cfg->hostapd_ssid.SSID_len,
+			(uint32)DOT11_MAX_SSID_LEN);
 		memcpy(join_params.ssid.SSID, cfg->hostapd_ssid.SSID,
-			cfg->hostapd_ssid.SSID_len);
-		join_params.ssid.SSID_len = htod32(cfg->hostapd_ssid.SSID_len);
+			join_params.ssid.SSID_len);
+		join_params.ssid.SSID_len = htod32(join_params.ssid.SSID_len);
 
 		/* create softap */
 		if ((err = wldev_ioctl(dev, WLC_SET_SSID, &join_params,
@@ -7249,20 +7255,22 @@ wl_cfg80211_add_set_beacon(struct wiphy *wiphy, struct net_device *dev,
 	}
 
 	ie_offset = DOT11_MGMT_HDR_LEN + DOT11_BCN_PRB_FIXED_LEN;
+
 	/* find the SSID */
 	if ((ssid_ie = bcm_parse_tlvs((u8 *)&info->head[ie_offset],
 		info->head_len - ie_offset,
 		DOT11_MNG_SSID_ID)) != NULL) {
 		if (dev_role == NL80211_IFTYPE_AP) {
 			/* Store the hostapd SSID */
-			memset(&cfg->hostapd_ssid.SSID[0], 0x00, 32);
-			memcpy(&cfg->hostapd_ssid.SSID[0], ssid_ie->data, ssid_ie->len);
-			cfg->hostapd_ssid.SSID_len = ssid_ie->len;
+			memset(&cfg->hostapd_ssid.SSID[0], 0x00, DOT11_MAX_SSID_LEN);
+			cfg->hostapd_ssid.SSID_len = MIN((int)ssid_ie->len, DOT11_MAX_SSID_LEN);
+			memcpy(&cfg->hostapd_ssid.SSID[0], ssid_ie->data,
+				cfg->hostapd_ssid.SSID_len);
 		} else {
-				/* P2P GO */
-			memset(&cfg->p2p->ssid.SSID[0], 0x00, 32);
-			memcpy(cfg->p2p->ssid.SSID, ssid_ie->data, ssid_ie->len);
-			cfg->p2p->ssid.SSID_len = ssid_ie->len;
+			/* P2P GO */
+			memset(&cfg->p2p->ssid.SSID[0], 0x00, DOT11_MAX_SSID_LEN);
+			cfg->p2p->ssid.SSID_len = MIN((int)ssid_ie->len, DOT11_MAX_SSID_LEN);
+			memcpy(cfg->p2p->ssid.SSID, ssid_ie->data, cfg->p2p->ssid.SSID_len);
 		}
 	}
 
@@ -7410,8 +7418,10 @@ wl_cfg80211_sched_scan_start(struct wiphy *wiphy,
 		ssid = &request->match_sets[i].ssid;
 		/* No need to include null ssid */
 		if (ssid->ssid_len) {
-			memcpy(ssids_local[ssid_cnt].SSID, ssid->ssid, ssid->ssid_len);
-			ssids_local[ssid_cnt].SSID_len = ssid->ssid_len;
+			ssids_local[ssid_cnt].SSID_len = MIN(ssid->ssid_len,
+				(uint32)DOT11_MAX_SSID_LEN);
+			memcpy(ssids_local[ssid_cnt].SSID, ssid->ssid,
+				ssids_local[ssid_cnt].SSID_len);
 			if (is_ssid_in_list(ssid, hidden_ssid_list, request->n_ssids)) {
 				ssids_local[ssid_cnt].hidden = TRUE;
 				WL_PNO((">>> PNO hidden SSID (%s) \n", ssid->ssid));
@@ -11800,8 +11810,8 @@ wl_update_prof(struct bcm_cfg80211 *cfg, struct net_device *ndev,
 		ssid = (wlc_ssid_t *) data;
 		memset(profile->ssid.SSID, 0,
 			sizeof(profile->ssid.SSID));
-		memcpy(profile->ssid.SSID, ssid->SSID, ssid->SSID_len);
-		profile->ssid.SSID_len = ssid->SSID_len;
+		profile->ssid.SSID_len = MIN(ssid->SSID_len, (uint32)DOT11_MAX_SSID_LEN);
+		memcpy(profile->ssid.SSID, ssid->SSID, profile->ssid.SSID_len);
 		break;
 	case WL_PROF_BSSID:
 		if (data)
@@ -11884,27 +11894,43 @@ static __used s32 wl_add_ie(struct bcm_cfg80211 *cfg, u8 t, u8 l, u8 *v)
 static void wl_update_hidden_ap_ie(struct wl_bss_info *bi, u8 *ie_stream, u32 *ie_size, bool roam)
 {
 	u8 *ssidie;
+	int32 ssid_len = MIN((int)bi->SSID_len, DOT11_MAX_SSID_LEN);
+	int32 remaining_ie_buf_len, available_buffer_len;
 	ssidie = (u8 *)cfg80211_find_ie(WLAN_EID_SSID, ie_stream, *ie_size);
+
+	/*
+	 * ERROR out if
+	 * 1. No ssid IE is FOUND or
+	 * 2. New ssid length is > what was allocated for existing ssid (as
+	 *    we do not want to overwrite the rest of the IEs) or
+	 * 3. If in case of erroneous buffer input where ssid length doesnt match the space
+	 *    allocated to it.
+	 */
 	if (!ssidie)
 		return;
-	if (ssidie[1] != bi->SSID_len) {
+
+	available_buffer_len = ((int)(*ie_size)) - (ssidie + 2 - ie_stream);
+	remaining_ie_buf_len = available_buffer_len - (int)ssidie[1];
+	if ((ssid_len > ssidie[1]) || (ssidie[1] > available_buffer_len))
+		return;
+
+	if (ssidie[1] != ssid_len) {
 		if (ssidie[1]) {
 			WL_ERR(("%s: Wrong SSID len: %d != %d\n",
 				__FUNCTION__, ssidie[1], bi->SSID_len));
 		}
 		if (roam) {
 			WL_ERR(("Changing the SSID Info.\n"));
-			memmove(ssidie + bi->SSID_len + 2,
-				(ssidie + 2) + ssidie[1],
-				*ie_size - (ssidie + 2 + ssidie[1] - ie_stream));
-			memcpy(ssidie + 2, bi->SSID, bi->SSID_len);
-			*ie_size = *ie_size + bi->SSID_len - ssidie[1];
-			ssidie[1] = bi->SSID_len;
+			memmove(ssidie + ssid_len + 2,
+				(ssidie + 2) + ssidie[1], remaining_ie_buf_len);
+			memcpy(ssidie + 2, bi->SSID, ssid_len);
+			*ie_size = *ie_size + ssid_len - ssidie[1];
+			ssidie[1] = ssid_len;
 		}
 		return;
 	}
 	if (*(ssidie + 2) == '\0')
-		 memcpy(ssidie + 2, bi->SSID, bi->SSID_len);
+		 memcpy(ssidie + 2, bi->SSID, ssid_len);
 	return;
 }