diff --git a/drivers/net/wireless/libertas/cfg.c b/drivers/net/wireless/libertas/cfg.c index ec36868f6fc50a50c2edcc8d8fee9e72153890f3..ec6d5d6b452e7aebf8b8d782460e7b0263c121a0 100644 --- a/drivers/net/wireless/libertas/cfg.c +++ b/drivers/net/wireless/libertas/cfg.c @@ -298,6 +298,7 @@ static int lbs_add_common_rates_tlv(u8 *tlv, struct cfg80211_bss *bss) const u8 *rates_eid, *ext_rates_eid; int n = 0; + rcu_read_lock(); rates_eid = ieee80211_bss_get_ie(bss, WLAN_EID_SUPP_RATES); ext_rates_eid = ieee80211_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES); @@ -325,6 +326,7 @@ static int lbs_add_common_rates_tlv(u8 *tlv, struct cfg80211_bss *bss) *tlv++ = 0x96; n = 4; } + rcu_read_unlock(); rate_tlv->header.len = cpu_to_le16(n); return sizeof(rate_tlv->header) + n; @@ -1140,11 +1142,13 @@ static int lbs_associate(struct lbs_private *priv, cmd->capability = cpu_to_le16(bss->capability); /* add SSID TLV */ + rcu_read_lock(); ssid_eid = ieee80211_bss_get_ie(bss, WLAN_EID_SSID); if (ssid_eid) pos += lbs_add_ssid_tlv(pos, ssid_eid + 2, ssid_eid[1]); else lbs_deb_assoc("no SSID\n"); + rcu_read_unlock(); /* add DS param TLV */ if (bss->channel) @@ -1782,7 +1786,7 @@ static int lbs_ibss_join_existing(struct lbs_private *priv, struct cfg80211_ibss_params *params, struct cfg80211_bss *bss) { - const u8 *rates_eid = ieee80211_bss_get_ie(bss, WLAN_EID_SUPP_RATES); + const u8 *rates_eid; struct cmd_ds_802_11_ad_hoc_join cmd; u8 preamble = RADIO_PREAMBLE_SHORT; int ret = 0; @@ -1841,6 +1845,8 @@ static int lbs_ibss_join_existing(struct lbs_private *priv, /* set rates to the intersection of our rates and the rates in the bss */ + rcu_read_lock(); + rates_eid = ieee80211_bss_get_ie(bss, WLAN_EID_SUPP_RATES); if (!rates_eid) { lbs_add_rates(cmd.bss.rates); } else { @@ -1860,6 +1866,7 @@ static int lbs_ibss_join_existing(struct lbs_private *priv, } } } + rcu_read_unlock(); /* Only v8 and below support setting this */ if (MRVL_FW_MAJOR_REV(priv->fwrelease) <= 8) { diff --git a/drivers/net/wireless/mwifiex/sta_ioctl.c b/drivers/net/wireless/mwifiex/sta_ioctl.c index 24af6ba7d8a19c0e4a8d920152b28e8e101e0691..5d7b83e2dc4df42607516f7f65c3f8983476a98f 100644 --- a/drivers/net/wireless/mwifiex/sta_ioctl.c +++ b/drivers/net/wireless/mwifiex/sta_ioctl.c @@ -158,12 +158,22 @@ int mwifiex_fill_new_bss_desc(struct mwifiex_private *priv, struct cfg80211_bss *bss, struct mwifiex_bssdescriptor *bss_desc) { - int ret; + int ret, beacon_ie_len; u8 *beacon_ie; struct mwifiex_bss_priv *bss_priv = (void *)bss->priv; + const struct cfg80211_bss_ies *ies; + + rcu_read_lock(); + ies = rcu_dereference(bss->ies); + if (WARN_ON(!ies)) { + /* should never happen */ + rcu_read_unlock(); + return -EINVAL; + } + beacon_ie = kmemdup(ies->data, ies->len, GFP_ATOMIC); + beacon_ie_len = ies->len; + rcu_read_unlock(); - beacon_ie = kmemdup(bss->information_elements, bss->len_beacon_ies, - GFP_KERNEL); if (!beacon_ie) { dev_err(priv->adapter->dev, " failed to alloc beacon_ie\n"); return -ENOMEM; @@ -172,7 +182,7 @@ int mwifiex_fill_new_bss_desc(struct mwifiex_private *priv, memcpy(bss_desc->mac_address, bss->bssid, ETH_ALEN); bss_desc->rssi = bss->signal; bss_desc->beacon_buf = beacon_ie; - bss_desc->beacon_buf_size = bss->len_beacon_ies; + bss_desc->beacon_buf_size = beacon_ie_len; bss_desc->beacon_period = bss->beacon_interval; bss_desc->cap_info_bitmap = bss->capability; bss_desc->bss_band = bss_priv->band; @@ -198,18 +208,23 @@ int mwifiex_fill_new_bss_desc(struct mwifiex_private *priv, static int mwifiex_process_country_ie(struct mwifiex_private *priv, struct cfg80211_bss *bss) { - u8 *country_ie, country_ie_len; + const u8 *country_ie; + u8 country_ie_len; struct mwifiex_802_11d_domain_reg *domain_info = &priv->adapter->domain_reg; - country_ie = (u8 *)ieee80211_bss_get_ie(bss, WLAN_EID_COUNTRY); - - if (!country_ie) + rcu_read_lock(); + country_ie = ieee80211_bss_get_ie(bss, WLAN_EID_COUNTRY); + if (!country_ie) { + rcu_read_unlock(); return 0; + } country_ie_len = country_ie[1]; - if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN) + if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN) { + rcu_read_unlock(); return 0; + } domain_info->country_code[0] = country_ie[2]; domain_info->country_code[1] = country_ie[3]; @@ -223,6 +238,8 @@ static int mwifiex_process_country_ie(struct mwifiex_private *priv, memcpy((u8 *)domain_info->triplet, &country_ie[2] + IEEE80211_COUNTRY_STRING_LEN, country_ie_len); + rcu_read_unlock(); + if (mwifiex_send_cmd_async(priv, HostCmd_CMD_802_11D_DOMAIN_INFO, HostCmd_ACT_GEN_SET, 0, NULL)) { wiphy_err(priv->adapter->wiphy, diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 731b48fa238b1755eb343525448207115b86ffaf..8e6a6b73b9c9ecc3f8f221c4ff32a9983940dde4 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1205,6 +1205,18 @@ enum cfg80211_signal_type { CFG80211_SIGNAL_TYPE_UNSPEC, }; +/** + * struct cfg80211_bss_ie_data - BSS entry IE data + * @rcu_head: internal use, for freeing + * @len: length of the IEs + * @data: IE data + */ +struct cfg80211_bss_ies { + struct rcu_head rcu_head; + int len; + u8 data[]; +}; + /** * struct cfg80211_bss - BSS description * @@ -1216,36 +1228,34 @@ enum cfg80211_signal_type { * @tsf: timestamp of last received update * @beacon_interval: the beacon interval as from the frame * @capability: the capability field in host byte order - * @information_elements: the information elements (Note that there + * @ies: the information elements (Note that there * is no guarantee that these are well-formed!); this is a pointer to * either the beacon_ies or proberesp_ies depending on whether Probe * Response frame has been received - * @len_information_elements: total length of the information elements * @beacon_ies: the information elements from the last Beacon frame - * @len_beacon_ies: total length of the beacon_ies * @proberesp_ies: the information elements from the last Probe Response frame - * @len_proberesp_ies: total length of the proberesp_ies * @signal: signal strength value (type depends on the wiphy's signal_type) * @free_priv: function pointer to free private data * @priv: private area for driver use, has at least wiphy->bss_priv_size bytes */ struct cfg80211_bss { + u64 tsf; + struct ieee80211_channel *channel; - u8 bssid[ETH_ALEN]; - u64 tsf; + const struct cfg80211_bss_ies __rcu *ies; + const struct cfg80211_bss_ies __rcu *beacon_ies; + const struct cfg80211_bss_ies __rcu *proberesp_ies; + + void (*free_priv)(struct cfg80211_bss *bss); + + s32 signal; + u16 beacon_interval; u16 capability; - u8 *information_elements; - size_t len_information_elements; - u8 *beacon_ies; - size_t len_beacon_ies; - u8 *proberesp_ies; - size_t len_proberesp_ies; - s32 signal; + u8 bssid[ETH_ALEN]; - void (*free_priv)(struct cfg80211_bss *bss); u8 priv[0] __attribute__((__aligned__(sizeof(void *)))); }; @@ -1253,6 +1263,9 @@ struct cfg80211_bss { * ieee80211_bss_get_ie - find IE with given ID * @bss: the bss to search * @ie: the IE ID + * + * Note that the return value is an RCU-protected pointer, so + * rcu_read_lock() must be held when calling this function. * Returns %NULL if not found. */ const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie); diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 35d8cffc973ac20b68765093530592e9fe70bb7c..481d5035b397ce9ff015209494e8dbee3069a30b 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -1382,19 +1382,26 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata, sdata->u.mgd.flags |= IEEE80211_STA_RESET_SIGNAL_AVE; if (sdata->vif.p2p) { - u8 noa[2]; - int ret; + const struct cfg80211_bss_ies *ies; - ret = cfg80211_get_p2p_attr(cbss->information_elements, - cbss->len_information_elements, - IEEE80211_P2P_ATTR_ABSENCE_NOTICE, - noa, sizeof(noa)); - if (ret >= 2) { - bss_conf->p2p_oppps = noa[1] & 0x80; - bss_conf->p2p_ctwindow = noa[1] & 0x7f; - bss_info_changed |= BSS_CHANGED_P2P_PS; - sdata->u.mgd.p2p_noa_index = noa[0]; + rcu_read_lock(); + ies = rcu_dereference(cbss->ies); + if (ies) { + u8 noa[2]; + int ret; + + ret = cfg80211_get_p2p_attr( + ies->data, ies->len, + IEEE80211_P2P_ATTR_ABSENCE_NOTICE, + noa, sizeof(noa)); + if (ret >= 2) { + bss_conf->p2p_oppps = noa[1] & 0x80; + bss_conf->p2p_ctwindow = noa[1] & 0x7f; + bss_info_changed |= BSS_CHANGED_P2P_PS; + sdata->u.mgd.p2p_noa_index = noa[0]; + } } + rcu_read_unlock(); } /* just to be sure */ @@ -1659,6 +1666,7 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata) } else { int ssid_len; + rcu_read_lock(); ssid = ieee80211_bss_get_ie(ifmgd->associated, WLAN_EID_SSID); if (WARN_ON_ONCE(ssid == NULL)) ssid_len = 0; @@ -1668,6 +1676,7 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata) ieee80211_send_probe_req(sdata, dst, ssid + 2, ssid_len, NULL, 0, (u32) -1, true, false, ifmgd->associated->channel, false); + rcu_read_unlock(); } ifmgd->probe_timeout = jiffies + msecs_to_jiffies(probe_wait_ms); @@ -1763,6 +1772,7 @@ struct sk_buff *ieee80211_ap_probereq_get(struct ieee80211_hw *hw, else return NULL; + rcu_read_lock(); ssid = ieee80211_bss_get_ie(cbss, WLAN_EID_SSID); if (WARN_ON_ONCE(ssid == NULL)) ssid_len = 0; @@ -1773,6 +1783,7 @@ struct sk_buff *ieee80211_ap_probereq_get(struct ieee80211_hw *hw, (u32) -1, cbss->channel, ssid + 2, ssid_len, NULL, 0, true); + rcu_read_unlock(); return skb; } @@ -2858,9 +2869,12 @@ static int ieee80211_probe_auth(struct ieee80211_sub_if_data *sdata) auth_data->bss->bssid, auth_data->tries, IEEE80211_AUTH_MAX_TRIES); + rcu_read_lock(); ssidie = ieee80211_bss_get_ie(auth_data->bss, WLAN_EID_SSID); - if (!ssidie) + if (!ssidie) { + rcu_read_unlock(); return -EINVAL; + } /* * Direct probe is sent to broadcast address as some APs * will not answer to direct packet in unassociated state. @@ -2868,6 +2882,7 @@ static int ieee80211_probe_auth(struct ieee80211_sub_if_data *sdata) ieee80211_send_probe_req(sdata, NULL, ssidie + 2, ssidie[1], NULL, 0, (u32) -1, true, false, auth_data->bss->channel, false); + rcu_read_unlock(); } auth_data->timeout = jiffies + IEEE80211_AUTH_TIMEOUT; @@ -3404,9 +3419,7 @@ static u8 ieee80211_ht_vht_rx_chains(struct ieee80211_sub_if_data *sdata, if (ifmgd->flags & IEEE80211_STA_DISABLE_HT) return chains; - ht_cap_ie = cfg80211_find_ie(WLAN_EID_HT_CAPABILITY, - cbss->information_elements, - cbss->len_information_elements); + ht_cap_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_CAPABILITY); if (ht_cap_ie && ht_cap_ie[1] >= sizeof(*ht_cap)) { ht_cap = (void *)(ht_cap_ie + 2); chains = ieee80211_mcs_to_chains(&ht_cap->mcs); @@ -3419,9 +3432,7 @@ static u8 ieee80211_ht_vht_rx_chains(struct ieee80211_sub_if_data *sdata, if (ifmgd->flags & IEEE80211_STA_DISABLE_VHT) return chains; - vht_cap_ie = cfg80211_find_ie(WLAN_EID_VHT_CAPABILITY, - cbss->information_elements, - cbss->len_information_elements); + vht_cap_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_VHT_CAPABILITY); if (vht_cap_ie && vht_cap_ie[1] >= sizeof(*vht_cap)) { u8 nss; u16 tx_mcs_map; @@ -3457,13 +3468,13 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata, IEEE80211_STA_DISABLE_80P80MHZ | IEEE80211_STA_DISABLE_160MHZ); + rcu_read_lock(); + if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT) && sband->ht_cap.ht_supported) { const u8 *ht_oper_ie; - ht_oper_ie = cfg80211_find_ie(WLAN_EID_HT_OPERATION, - cbss->information_elements, - cbss->len_information_elements); + ht_oper_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_OPERATION); if (ht_oper_ie && ht_oper_ie[1] >= sizeof(*ht_oper)) ht_oper = (void *)(ht_oper_ie + 2); } @@ -3472,9 +3483,8 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata, sband->vht_cap.vht_supported) { const u8 *vht_oper_ie; - vht_oper_ie = cfg80211_find_ie(WLAN_EID_VHT_OPERATION, - cbss->information_elements, - cbss->len_information_elements); + vht_oper_ie = ieee80211_bss_get_ie(cbss, + WLAN_EID_VHT_OPERATION); if (vht_oper_ie && vht_oper_ie[1] >= sizeof(*vht_oper)) vht_oper = (void *)(vht_oper_ie + 2); if (vht_oper && !ht_oper) { @@ -3494,6 +3504,8 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata, sdata->needed_rx_chains = min(ieee80211_ht_vht_rx_chains(sdata, cbss), local->rx_chains); + rcu_read_unlock(); + /* will change later if needed */ sdata->smps_mode = IEEE80211_SMPS_OFF; @@ -3734,14 +3746,21 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata, const u8 *ssidie, *ht_ie; int i, err; - ssidie = ieee80211_bss_get_ie(req->bss, WLAN_EID_SSID); - if (!ssidie) - return -EINVAL; - assoc_data = kzalloc(sizeof(*assoc_data) + req->ie_len, GFP_KERNEL); if (!assoc_data) return -ENOMEM; + rcu_read_lock(); + ssidie = ieee80211_bss_get_ie(req->bss, WLAN_EID_SSID); + if (!ssidie) { + rcu_read_unlock(); + kfree(assoc_data); + return -EINVAL; + } + memcpy(assoc_data->ssid, ssidie + 2, ssidie[1]); + assoc_data->ssid_len = ssidie[1]; + rcu_read_unlock(); + mutex_lock(&ifmgd->mtx); if (ifmgd->associated) @@ -3836,12 +3855,14 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata, assoc_data->supp_rates = bss->supp_rates; assoc_data->supp_rates_len = bss->supp_rates_len; + rcu_read_lock(); ht_ie = ieee80211_bss_get_ie(req->bss, WLAN_EID_HT_OPERATION); if (ht_ie && ht_ie[1] >= sizeof(struct ieee80211_ht_operation)) assoc_data->ap_ht_param = ((struct ieee80211_ht_operation *)(ht_ie + 2))->ht_param; else ifmgd->flags |= IEEE80211_STA_DISABLE_HT; + rcu_read_unlock(); if (bss->wmm_used && bss->uapsd_supported && (sdata->local->hw.flags & IEEE80211_HW_SUPPORTS_UAPSD)) { @@ -3852,9 +3873,6 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata, ifmgd->flags &= ~IEEE80211_STA_UAPSD_ENABLED; } - memcpy(assoc_data->ssid, ssidie + 2, ssidie[1]); - assoc_data->ssid_len = ssidie[1]; - if (req->prev_bssid) memcpy(assoc_data->prev_bssid, req->prev_bssid, ETH_ALEN); diff --git a/net/wireless/core.h b/net/wireless/core.h index 6183a0d25b8bcd1649152a57bf6dd4aff239e86e..3563097169cb3ca8b767e9f5398a741c03a9885b 100644 --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -138,8 +138,6 @@ struct cfg80211_internal_bss { unsigned long ts; struct kref ref; atomic_t hold; - bool beacon_ies_allocated; - bool proberesp_ies_allocated; /* must be last because of priv member */ struct cfg80211_bss pub; diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 4a719770eaaf432c841e25799df3de48600e178e..f45706adaf3411813133704d41a12aa9d1d59712 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -4808,6 +4808,7 @@ static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb, struct cfg80211_internal_bss *intbss) { struct cfg80211_bss *res = &intbss->pub; + const struct cfg80211_bss_ies *ies; void *hdr; struct nlattr *bss; @@ -4828,16 +4829,24 @@ static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb, if (!bss) goto nla_put_failure; if ((!is_zero_ether_addr(res->bssid) && - nla_put(msg, NL80211_BSS_BSSID, ETH_ALEN, res->bssid)) || - (res->information_elements && res->len_information_elements && - nla_put(msg, NL80211_BSS_INFORMATION_ELEMENTS, - res->len_information_elements, - res->information_elements)) || - (res->beacon_ies && res->len_beacon_ies && - res->beacon_ies != res->information_elements && - nla_put(msg, NL80211_BSS_BEACON_IES, - res->len_beacon_ies, res->beacon_ies))) + nla_put(msg, NL80211_BSS_BSSID, ETH_ALEN, res->bssid))) goto nla_put_failure; + + rcu_read_lock(); + ies = rcu_dereference(res->ies); + if (ies && ies->len && nla_put(msg, NL80211_BSS_INFORMATION_ELEMENTS, + ies->len, ies->data)) { + rcu_read_unlock(); + goto nla_put_failure; + } + ies = rcu_dereference(res->beacon_ies); + if (ies && ies->len && nla_put(msg, NL80211_BSS_BEACON_IES, + ies->len, ies->data)) { + rcu_read_unlock(); + goto nla_put_failure; + } + rcu_read_unlock(); + if (res->tsf && nla_put_u64(msg, NL80211_BSS_TSF, res->tsf)) goto nla_put_failure; diff --git a/net/wireless/reg.c b/net/wireless/reg.c index bcc7d7ee5a516b8263c93a2556ab079d6d369280..b6c7ea6d98f8a313cda103cdfce1adb1e9cf0be3 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -1797,7 +1797,7 @@ EXPORT_SYMBOL(regulatory_hint); */ void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band, - u8 *country_ie, + const u8 *country_ie, u8 country_ie_len) { char alpha2[2]; diff --git a/net/wireless/reg.h b/net/wireless/reg.h index f023c8a31c60bc82ad54659957169cd0d974d074..4c0a32ffd530daabb18912edb827c968456a26fa 100644 --- a/net/wireless/reg.h +++ b/net/wireless/reg.h @@ -81,7 +81,7 @@ int regulatory_hint_found_beacon(struct wiphy *wiphy, */ void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band, - u8 *country_ie, + const u8 *country_ie, u8 country_ie_len); /** diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 834e0d153fbe69e59a7bbc0535481bee0b1b3127..01592d7d4789e389fd565e7cf9fb194dc7ee7bb0 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -23,6 +23,7 @@ static void bss_release(struct kref *ref) { + struct cfg80211_bss_ies *ies; struct cfg80211_internal_bss *bss; bss = container_of(ref, struct cfg80211_internal_bss, ref); @@ -33,10 +34,12 @@ static void bss_release(struct kref *ref) if (bss->pub.free_priv) bss->pub.free_priv(&bss->pub); - if (bss->beacon_ies_allocated) - kfree(bss->pub.beacon_ies); - if (bss->proberesp_ies_allocated) - kfree(bss->pub.proberesp_ies); + ies = (void *)rcu_access_pointer(bss->pub.beacon_ies); + if (ies) + kfree_rcu(ies, rcu_head); + ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies); + if (ies) + kfree_rcu(ies, rcu_head); kfree(bss); } @@ -288,7 +291,7 @@ const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type, } EXPORT_SYMBOL(cfg80211_find_vendor_ie); -static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2) +static int cmp_ies(u8 num, const u8 *ies1, int len1, const u8 *ies2, int len2) { const u8 *ie1 = cfg80211_find_ie(num, ies1, len1); const u8 *ie2 = cfg80211_find_ie(num, ies2, len2); @@ -311,6 +314,7 @@ static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2) static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, const u8 *ssid, size_t ssid_len) { + const struct cfg80211_bss_ies *ies; const u8 *ssidie; if (bssid && !ether_addr_equal(a->bssid, bssid)) @@ -319,9 +323,10 @@ static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, if (!ssid) return true; - ssidie = cfg80211_find_ie(WLAN_EID_SSID, - a->information_elements, - a->len_information_elements); + ies = rcu_access_pointer(a->ies); + if (!ies) + return false; + ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); if (!ssidie) return false; if (ssidie[1] != ssid_len) @@ -331,20 +336,21 @@ static bool is_bss(struct cfg80211_bss *a, const u8 *bssid, static bool is_mesh_bss(struct cfg80211_bss *a) { + const struct cfg80211_bss_ies *ies; const u8 *ie; if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability)) return false; - ie = cfg80211_find_ie(WLAN_EID_MESH_ID, - a->information_elements, - a->len_information_elements); + ies = rcu_access_pointer(a->ies); + if (!ies) + return false; + + ie = cfg80211_find_ie(WLAN_EID_MESH_ID, ies->data, ies->len); if (!ie) return false; - ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, - a->information_elements, - a->len_information_elements); + ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, ies->data, ies->len); if (!ie) return false; @@ -355,14 +361,17 @@ static bool is_mesh(struct cfg80211_bss *a, const u8 *meshid, size_t meshidlen, const u8 *meshcfg) { + const struct cfg80211_bss_ies *ies; const u8 *ie; if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability)) return false; - ie = cfg80211_find_ie(WLAN_EID_MESH_ID, - a->information_elements, - a->len_information_elements); + ies = rcu_access_pointer(a->ies); + if (!ies) + return false; + + ie = cfg80211_find_ie(WLAN_EID_MESH_ID, ies->data, ies->len); if (!ie) return false; if (ie[1] != meshidlen) @@ -370,9 +379,7 @@ static bool is_mesh(struct cfg80211_bss *a, if (memcmp(ie + 2, meshid, meshidlen)) return false; - ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, - a->information_elements, - a->len_information_elements); + ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, ies->data, ies->len); if (!ie) return false; if (ie[1] != sizeof(struct ieee80211_meshconf_ie)) @@ -389,24 +396,28 @@ static bool is_mesh(struct cfg80211_bss *a, static int cmp_bss_core(struct cfg80211_bss *a, struct cfg80211_bss *b) { + const struct cfg80211_bss_ies *a_ies, *b_ies; int r; if (a->channel != b->channel) return b->channel->center_freq - a->channel->center_freq; if (is_mesh_bss(a) && is_mesh_bss(b)) { + a_ies = rcu_access_pointer(a->ies); + if (!a_ies) + return -1; + b_ies = rcu_access_pointer(b->ies); + if (!b_ies) + return 1; + r = cmp_ies(WLAN_EID_MESH_ID, - a->information_elements, - a->len_information_elements, - b->information_elements, - b->len_information_elements); + a_ies->data, a_ies->len, + b_ies->data, b_ies->len); if (r) return r; return cmp_ies(WLAN_EID_MESH_CONFIG, - a->information_elements, - a->len_information_elements, - b->information_elements, - b->len_information_elements); + a_ies->data, a_ies->len, + b_ies->data, b_ies->len); } /* @@ -419,21 +430,28 @@ static int cmp_bss_core(struct cfg80211_bss *a, struct cfg80211_bss *b) static int cmp_bss(struct cfg80211_bss *a, struct cfg80211_bss *b) { + const struct cfg80211_bss_ies *a_ies, *b_ies; int r; r = cmp_bss_core(a, b); if (r) return r; + a_ies = rcu_access_pointer(a->ies); + if (!a_ies) + return -1; + b_ies = rcu_access_pointer(b->ies); + if (!b_ies) + return 1; + return cmp_ies(WLAN_EID_SSID, - a->information_elements, - a->len_information_elements, - b->information_elements, - b->len_information_elements); + a_ies->data, a_ies->len, + b_ies->data, b_ies->len); } static int cmp_hidden_bss(struct cfg80211_bss *a, struct cfg80211_bss *b) { + const struct cfg80211_bss_ies *a_ies, *b_ies; const u8 *ie1; const u8 *ie2; int i; @@ -443,12 +461,15 @@ static int cmp_hidden_bss(struct cfg80211_bss *a, struct cfg80211_bss *b) if (r) return r; - ie1 = cfg80211_find_ie(WLAN_EID_SSID, - a->information_elements, - a->len_information_elements); - ie2 = cfg80211_find_ie(WLAN_EID_SSID, - b->information_elements, - b->len_information_elements); + a_ies = rcu_access_pointer(a->ies); + if (!a_ies) + return -1; + b_ies = rcu_access_pointer(b->ies); + if (!b_ies) + return 1; + + ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len); + ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len); /* * Key comparator must use same algorithm in any rb-tree @@ -633,126 +654,84 @@ static void copy_hidden_ies(struct cfg80211_internal_bss *res, struct cfg80211_internal_bss *hidden) { - if (unlikely(res->pub.beacon_ies)) - return; - if (WARN_ON(!hidden->pub.beacon_ies)) + const struct cfg80211_bss_ies *ies; + + if (rcu_access_pointer(res->pub.beacon_ies)) return; - res->pub.beacon_ies = kmalloc(hidden->pub.len_beacon_ies, GFP_ATOMIC); - if (unlikely(!res->pub.beacon_ies)) + ies = rcu_access_pointer(hidden->pub.beacon_ies); + if (WARN_ON(!ies)) return; - res->beacon_ies_allocated = true; - res->pub.len_beacon_ies = hidden->pub.len_beacon_ies; - memcpy(res->pub.beacon_ies, hidden->pub.beacon_ies, - res->pub.len_beacon_ies); + ies = kmemdup(ies, sizeof(*ies) + ies->len, GFP_ATOMIC); + if (unlikely(!ies)) + return; + rcu_assign_pointer(res->pub.beacon_ies, ies); } static struct cfg80211_internal_bss * cfg80211_bss_update(struct cfg80211_registered_device *dev, - struct cfg80211_internal_bss *res) + struct cfg80211_internal_bss *tmp) { struct cfg80211_internal_bss *found = NULL; - /* - * The reference to "res" is donated to this function. - */ - - if (WARN_ON(!res->pub.channel)) { - kref_put(&res->ref, bss_release); + if (WARN_ON(!tmp->pub.channel)) return NULL; - } - res->ts = jiffies; + tmp->ts = jiffies; spin_lock_bh(&dev->bss_lock); - found = rb_find_bss(dev, res); + if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) { + spin_unlock_bh(&dev->bss_lock); + return NULL; + } + + found = rb_find_bss(dev, tmp); if (found) { - found->pub.beacon_interval = res->pub.beacon_interval; - found->pub.tsf = res->pub.tsf; - found->pub.signal = res->pub.signal; - found->pub.capability = res->pub.capability; - found->ts = res->ts; + found->pub.beacon_interval = tmp->pub.beacon_interval; + found->pub.tsf = tmp->pub.tsf; + found->pub.signal = tmp->pub.signal; + found->pub.capability = tmp->pub.capability; + found->ts = tmp->ts; /* Update IEs */ - if (res->pub.proberesp_ies) { - size_t used = dev->wiphy.bss_priv_size + sizeof(*res); - size_t ielen = res->pub.len_proberesp_ies; - - if (found->pub.proberesp_ies && - !found->proberesp_ies_allocated && - ksize(found) >= used + ielen) { - memcpy(found->pub.proberesp_ies, - res->pub.proberesp_ies, ielen); - found->pub.len_proberesp_ies = ielen; - } else { - u8 *ies = found->pub.proberesp_ies; - - if (found->proberesp_ies_allocated) - ies = krealloc(ies, ielen, GFP_ATOMIC); - else - ies = kmalloc(ielen, GFP_ATOMIC); - - if (ies) { - memcpy(ies, res->pub.proberesp_ies, - ielen); - found->proberesp_ies_allocated = true; - found->pub.proberesp_ies = ies; - found->pub.len_proberesp_ies = ielen; - } - } + if (rcu_access_pointer(tmp->pub.proberesp_ies)) { + const struct cfg80211_bss_ies *old; + + old = rcu_access_pointer(found->pub.proberesp_ies); + rcu_assign_pointer(found->pub.proberesp_ies, + tmp->pub.proberesp_ies); /* Override possible earlier Beacon frame IEs */ - found->pub.information_elements = - found->pub.proberesp_ies; - found->pub.len_information_elements = - found->pub.len_proberesp_ies; - } + rcu_assign_pointer(found->pub.ies, + tmp->pub.proberesp_ies); + if (old) + kfree_rcu((struct cfg80211_bss_ies *)old, + rcu_head); + } else if (rcu_access_pointer(tmp->pub.beacon_ies)) { + const struct cfg80211_bss_ies *old, *ies; - if (res->pub.beacon_ies) { - size_t used = dev->wiphy.bss_priv_size + sizeof(*res); - size_t ielen = res->pub.len_beacon_ies; - bool information_elements_is_beacon_ies = - (found->pub.information_elements == - found->pub.beacon_ies); - - if (found->pub.beacon_ies && - !found->beacon_ies_allocated && - ksize(found) >= used + ielen) { - memcpy(found->pub.beacon_ies, - res->pub.beacon_ies, ielen); - found->pub.len_beacon_ies = ielen; - } else { - u8 *ies = found->pub.beacon_ies; - - if (found->beacon_ies_allocated) - ies = krealloc(ies, ielen, GFP_ATOMIC); - else - ies = kmalloc(ielen, GFP_ATOMIC); - - if (ies) { - memcpy(ies, res->pub.beacon_ies, - ielen); - found->beacon_ies_allocated = true; - found->pub.beacon_ies = ies; - found->pub.len_beacon_ies = ielen; - } - } + old = rcu_access_pointer(found->pub.beacon_ies); + ies = rcu_access_pointer(found->pub.ies); + + rcu_assign_pointer(found->pub.beacon_ies, + tmp->pub.beacon_ies); /* Override IEs if they were from a beacon before */ - if (information_elements_is_beacon_ies) { - found->pub.information_elements = - found->pub.beacon_ies; - found->pub.len_information_elements = - found->pub.len_beacon_ies; - } - } + if (old == ies) + rcu_assign_pointer(found->pub.ies, + tmp->pub.beacon_ies); - kref_put(&res->ref, bss_release); + if (old) + kfree_rcu((struct cfg80211_bss_ies *)old, + rcu_head); + } } else { + struct cfg80211_internal_bss *new; struct cfg80211_internal_bss *hidden; + struct cfg80211_bss_ies *ies; /* First check if the beacon is a probe response from * a hidden bss. If so, copy beacon ies (with nullified @@ -763,14 +742,32 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev, /* TODO: The code is not trying to update existing probe * response bss entries when beacon ies are * getting changed. */ - hidden = rb_find_hidden_bss(dev, res); + hidden = rb_find_hidden_bss(dev, tmp); if (hidden) - copy_hidden_ies(res, hidden); - - /* this "consumes" the reference */ - list_add_tail(&res->list, &dev->bss_list); - rb_insert_bss(dev, res); - found = res; + copy_hidden_ies(tmp, hidden); + + /* + * create a copy -- the "res" variable that is passed in + * is allocated on the stack since it's not needed in the + * more common case of an update + */ + new = kzalloc(sizeof(*new) + dev->wiphy.bss_priv_size, + GFP_ATOMIC); + if (!new) { + ies = (void *)rcu_dereference(tmp->pub.beacon_ies); + if (ies) + kfree_rcu(ies, rcu_head); + ies = (void *)rcu_dereference(tmp->pub.proberesp_ies); + if (ies) + kfree_rcu(ies, rcu_head); + spin_unlock_bh(&dev->bss_lock); + return NULL; + } + memcpy(new, tmp, sizeof(*new)); + kref_init(&new->ref); + list_add_tail(&new->list, &dev->bss_list); + rb_insert_bss(dev, new); + found = new; } dev->bss_generation++; @@ -819,14 +816,12 @@ cfg80211_inform_bss(struct wiphy *wiphy, u16 beacon_interval, const u8 *ie, size_t ielen, s32 signal, gfp_t gfp) { - struct cfg80211_internal_bss *res; - size_t privsz; + struct cfg80211_bss_ies *ies; + struct cfg80211_internal_bss tmp = {}, *res; if (WARN_ON(!wiphy)) return NULL; - privsz = wiphy->bss_priv_size; - if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC && (signal < 0 || signal > 100))) return NULL; @@ -835,36 +830,33 @@ cfg80211_inform_bss(struct wiphy *wiphy, if (!channel) return NULL; - res = kzalloc(sizeof(*res) + privsz + ielen, gfp); - if (!res) - return NULL; - - memcpy(res->pub.bssid, bssid, ETH_ALEN); - res->pub.channel = channel; - res->pub.signal = signal; - res->pub.tsf = tsf; - res->pub.beacon_interval = beacon_interval; - res->pub.capability = capability; + memcpy(tmp.pub.bssid, bssid, ETH_ALEN); + tmp.pub.channel = channel; + tmp.pub.signal = signal; + tmp.pub.tsf = tsf; + tmp.pub.beacon_interval = beacon_interval; + tmp.pub.capability = capability; /* * Since we do not know here whether the IEs are from a Beacon or Probe * Response frame, we need to pick one of the options and only use it * with the driver that does not provide the full Beacon/Probe Response * frame. Use Beacon frame pointer to avoid indicating that this should - * override the information_elements pointer should we have received an - * earlier indication of Probe Response data. + * override the iies pointer should we have received an earlier + * indication of Probe Response data. * * The initial buffer for the IEs is allocated with the BSS entry and * is located after the private area. */ - res->pub.beacon_ies = (u8 *)res + sizeof(*res) + privsz; - memcpy(res->pub.beacon_ies, ie, ielen); - res->pub.len_beacon_ies = ielen; - res->pub.information_elements = res->pub.beacon_ies; - res->pub.len_information_elements = res->pub.len_beacon_ies; + ies = kmalloc(sizeof(*ies) + ielen, gfp); + if (!ies) + return NULL; + ies->len = ielen; + memcpy(ies->data, ie, ielen); - kref_init(&res->ref); + rcu_assign_pointer(tmp.pub.beacon_ies, ies); + rcu_assign_pointer(tmp.pub.ies, ies); - res = cfg80211_bss_update(wiphy_to_dev(wiphy), res); + res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp); if (!res) return NULL; @@ -883,10 +875,10 @@ cfg80211_inform_bss_frame(struct wiphy *wiphy, struct ieee80211_mgmt *mgmt, size_t len, s32 signal, gfp_t gfp) { - struct cfg80211_internal_bss *res; + struct cfg80211_internal_bss tmp = {}, *res; + struct cfg80211_bss_ies *ies; size_t ielen = len - offsetof(struct ieee80211_mgmt, u.probe_resp.variable); - size_t privsz; BUILD_BUG_ON(offsetof(struct ieee80211_mgmt, u.probe_resp.variable) != offsetof(struct ieee80211_mgmt, u.beacon.variable)); @@ -906,45 +898,31 @@ cfg80211_inform_bss_frame(struct wiphy *wiphy, if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable))) return NULL; - privsz = wiphy->bss_priv_size; - channel = cfg80211_get_bss_channel(wiphy, mgmt->u.beacon.variable, ielen, channel); if (!channel) return NULL; - res = kzalloc(sizeof(*res) + privsz + ielen, gfp); - if (!res) + ies = kmalloc(sizeof(*ies) + ielen, gfp); + if (!ies) return NULL; + ies->len = ielen; + memcpy(ies->data, mgmt->u.probe_resp.variable, ielen); - memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN); - res->pub.channel = channel; - res->pub.signal = signal; - res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); - res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); - res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); - /* - * The initial buffer for the IEs is allocated with the BSS entry and - * is located after the private area. - */ - if (ieee80211_is_probe_resp(mgmt->frame_control)) { - res->pub.proberesp_ies = (u8 *) res + sizeof(*res) + privsz; - memcpy(res->pub.proberesp_ies, mgmt->u.probe_resp.variable, - ielen); - res->pub.len_proberesp_ies = ielen; - res->pub.information_elements = res->pub.proberesp_ies; - res->pub.len_information_elements = res->pub.len_proberesp_ies; - } else { - res->pub.beacon_ies = (u8 *) res + sizeof(*res) + privsz; - memcpy(res->pub.beacon_ies, mgmt->u.beacon.variable, ielen); - res->pub.len_beacon_ies = ielen; - res->pub.information_elements = res->pub.beacon_ies; - res->pub.len_information_elements = res->pub.len_beacon_ies; - } - - kref_init(&res->ref); - - res = cfg80211_bss_update(wiphy_to_dev(wiphy), res); + if (ieee80211_is_probe_resp(mgmt->frame_control)) + rcu_assign_pointer(tmp.pub.proberesp_ies, ies); + else + rcu_assign_pointer(tmp.pub.beacon_ies, ies); + rcu_assign_pointer(tmp.pub.ies, ies); + + memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN); + tmp.pub.channel = channel; + tmp.pub.signal = signal; + tmp.pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp); + tmp.pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int); + tmp.pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info); + + res = cfg80211_bss_update(wiphy_to_dev(wiphy), &tmp); if (!res) return NULL; @@ -1136,22 +1114,21 @@ int cfg80211_wext_siwscan(struct net_device *dev, EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan); static void ieee80211_scan_add_ies(struct iw_request_info *info, - struct cfg80211_bss *bss, + const struct cfg80211_bss_ies *ies, char **current_ev, char *end_buf) { - u8 *pos, *end, *next; + const u8 *pos, *end, *next; struct iw_event iwe; - if (!bss->information_elements || - !bss->len_information_elements) + if (!ies) return; /* * If needed, fragment the IEs buffer (at IE boundaries) into short * enough fragments to fit into IW_GENERIC_IE_MAX octet messages. */ - pos = bss->information_elements; - end = pos + bss->len_information_elements; + pos = ies->data; + end = pos + ies->len; while (end - pos > IW_GENERIC_IE_MAX) { next = pos + 2 + pos[1]; @@ -1162,7 +1139,8 @@ static void ieee80211_scan_add_ies(struct iw_request_info *info, iwe.cmd = IWEVGENIE; iwe.u.data.length = next - pos; *current_ev = iwe_stream_add_point(info, *current_ev, - end_buf, &iwe, pos); + end_buf, &iwe, + (void *)pos); pos = next; } @@ -1172,7 +1150,8 @@ static void ieee80211_scan_add_ies(struct iw_request_info *info, iwe.cmd = IWEVGENIE; iwe.u.data.length = end - pos; *current_ev = iwe_stream_add_point(info, *current_ev, - end_buf, &iwe, pos); + end_buf, &iwe, + (void *)pos); } } @@ -1191,10 +1170,11 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, struct cfg80211_internal_bss *bss, char *current_ev, char *end_buf) { + const struct cfg80211_bss_ies *ies; struct iw_event iwe; + const u8 *ie; u8 *buf, *cfg, *p; - u8 *ie = bss->pub.information_elements; - int rem = bss->pub.len_information_elements, i, sig; + int rem, i, sig; bool ismesh = false; memset(&iwe, 0, sizeof(iwe)); @@ -1259,7 +1239,17 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, current_ev = iwe_stream_add_point(info, current_ev, end_buf, &iwe, ""); - while (rem >= 2) { + rcu_read_lock(); + ies = rcu_dereference(bss->pub.ies); + if (ies) { + rem = ies->len; + ie = ies->data; + } else { + rem = 0; + ie = NULL; + } + + while (ies && rem >= 2) { /* invalid data */ if (ie[1] > rem - 2) break; @@ -1271,7 +1261,7 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, iwe.u.data.length = ie[1]; iwe.u.data.flags = 1; current_ev = iwe_stream_add_point(info, current_ev, end_buf, - &iwe, ie + 2); + &iwe, (u8 *)ie + 2); break; case WLAN_EID_MESH_ID: memset(&iwe, 0, sizeof(iwe)); @@ -1279,7 +1269,7 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, iwe.u.data.length = ie[1]; iwe.u.data.flags = 1; current_ev = iwe_stream_add_point(info, current_ev, end_buf, - &iwe, ie + 2); + &iwe, (u8 *)ie + 2); break; case WLAN_EID_MESH_CONFIG: ismesh = true; @@ -1288,7 +1278,7 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, buf = kmalloc(50, GFP_ATOMIC); if (!buf) break; - cfg = ie + 2; + cfg = (u8 *)ie + 2; memset(&iwe, 0, sizeof(iwe)); iwe.cmd = IWEVCUSTOM; sprintf(buf, "Mesh Network Path Selection Protocol ID: " @@ -1386,7 +1376,8 @@ ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info, kfree(buf); } - ieee80211_scan_add_ies(info, &bss->pub, ¤t_ev, end_buf); + ieee80211_scan_add_ies(info, ies, ¤t_ev, end_buf); + rcu_read_unlock(); return current_ev; } diff --git a/net/wireless/sme.c b/net/wireless/sme.c index c7490027237d2984e267b1bbdec6693d6cb49d8c..f2431e41a373d47b12422642b73e00068834cdd7 100644 --- a/net/wireless/sme.c +++ b/net/wireless/sme.c @@ -417,7 +417,7 @@ void __cfg80211_connect_result(struct net_device *dev, const u8 *bssid, struct cfg80211_bss *bss) { struct wireless_dev *wdev = dev->ieee80211_ptr; - u8 *country_ie; + const u8 *country_ie; #ifdef CONFIG_CFG80211_WEXT union iwreq_data wrqu; #endif @@ -501,7 +501,15 @@ void __cfg80211_connect_result(struct net_device *dev, const u8 *bssid, wdev->sme_state = CFG80211_SME_CONNECTED; cfg80211_upload_connect_keys(wdev); - country_ie = (u8 *) ieee80211_bss_get_ie(bss, WLAN_EID_COUNTRY); + rcu_read_lock(); + country_ie = ieee80211_bss_get_ie(bss, WLAN_EID_COUNTRY); + if (!country_ie) { + rcu_read_unlock(); + return; + } + + country_ie = kmemdup(country_ie, 2 + country_ie[1], GFP_ATOMIC); + rcu_read_unlock(); if (!country_ie) return; @@ -515,6 +523,7 @@ void __cfg80211_connect_result(struct net_device *dev, const u8 *bssid, bss->channel->band, country_ie + 2, country_ie[1]); + kfree(country_ie); } void cfg80211_connect_result(struct net_device *dev, const u8 *bssid, diff --git a/net/wireless/util.c b/net/wireless/util.c index 3cce6e486219d369a2e823ff5f741f24d2d4902e..16d76a807c2fac022294aa33cb0336bb89bab38b 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -688,10 +688,13 @@ EXPORT_SYMBOL(cfg80211_classify8021d); const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie) { - if (bss->information_elements == NULL) + const struct cfg80211_bss_ies *ies; + + ies = rcu_dereference(bss->ies); + if (!ies) return NULL; - return cfg80211_find_ie(ie, bss->information_elements, - bss->len_information_elements); + + return cfg80211_find_ie(ie, ies->data, ies->len); } EXPORT_SYMBOL(ieee80211_bss_get_ie); diff --git a/net/wireless/wext-sme.c b/net/wireless/wext-sme.c index 873af63187c0c52bdc194d0620a4b946560b6e9c..fb9622f6d99c4b6b6c87f8a8d8e2c88e4fb3705c 100644 --- a/net/wireless/wext-sme.c +++ b/net/wireless/wext-sme.c @@ -242,13 +242,17 @@ int cfg80211_mgd_wext_giwessid(struct net_device *dev, wdev_lock(wdev); if (wdev->current_bss) { - const u8 *ie = ieee80211_bss_get_ie(&wdev->current_bss->pub, - WLAN_EID_SSID); + const u8 *ie; + + rcu_read_lock(); + ie = ieee80211_bss_get_ie(&wdev->current_bss->pub, + WLAN_EID_SSID); if (ie) { data->flags = 1; data->length = ie[1]; memcpy(ssid, ie + 2, data->length); } + rcu_read_unlock(); } else if (wdev->wext.connect.ssid && wdev->wext.connect.ssid_len) { data->flags = 1; data->length = wdev->wext.connect.ssid_len;