nl80211: don't put struct cfg80211_ap_settings on stack

This struct has grown quite a bit, so dynamically allocate
it instead of putting it on the stack.

Link: https://lore.kernel.org/r/20210923161836.5813d881eae3.I0fc0f83905b0bfa332c4f1505e00c13abfca3545@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index e4787c74e80b17ce2b4385b71ab39a2496596f12..0b4f29d689d270461a1c181dd635525538e61455 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5323,7 +5323,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
        struct cfg80211_registered_device *rdev = info->user_ptr[0];
        struct net_device *dev = info->user_ptr[1];
        struct wireless_dev *wdev = dev->ieee80211_ptr;
-       struct cfg80211_ap_settings params;
+       struct cfg80211_ap_settings *params;
        int err;
 
        if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP &&
@@ -5336,27 +5336,29 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
        if (wdev->beacon_interval)
                return -EALREADY;
 
-       memset(&params, 0, sizeof(params));
-
        /* these are required for START_AP */
        if (!info->attrs[NL80211_ATTR_BEACON_INTERVAL] ||
            !info->attrs[NL80211_ATTR_DTIM_PERIOD] ||
            !info->attrs[NL80211_ATTR_BEACON_HEAD])
                return -EINVAL;
 
-       err = nl80211_parse_beacon(rdev, info->attrs, &params.beacon);
+       params = kzalloc(sizeof(*params), GFP_KERNEL);
+       if (!params)
+               return -ENOMEM;
+
+       err = nl80211_parse_beacon(rdev, info->attrs, &params->beacon);
        if (err)
-               return err;
+               goto out;
 
-       params.beacon_interval =
+       params->beacon_interval =
                nla_get_u32(info->attrs[NL80211_ATTR_BEACON_INTERVAL]);
-       params.dtim_period =
+       params->dtim_period =
                nla_get_u32(info->attrs[NL80211_ATTR_DTIM_PERIOD]);
 
        err = cfg80211_validate_beacon_int(rdev, dev->ieee80211_ptr->iftype,
-                                          params.beacon_interval);
+                                          params->beacon_interval);
        if (err)
-               return err;
+               goto out;
 
        /*
         * In theory, some of these attributes should be required here
@@ -5366,129 +5368,156 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
         * additional information -- drivers must check!
         */
        if (info->attrs[NL80211_ATTR_SSID]) {
-               params.ssid = nla_data(info->attrs[NL80211_ATTR_SSID]);
-               params.ssid_len =
+               params->ssid = nla_data(info->attrs[NL80211_ATTR_SSID]);
+               params->ssid_len =
                        nla_len(info->attrs[NL80211_ATTR_SSID]);
-               if (params.ssid_len == 0)
-                       return -EINVAL;
+               if (params->ssid_len == 0) {
+                       err = -EINVAL;
+                       goto out;
+               }
        }
 
        if (info->attrs[NL80211_ATTR_HIDDEN_SSID])
-               params.hidden_ssid = nla_get_u32(
+               params->hidden_ssid = nla_get_u32(
                        info->attrs[NL80211_ATTR_HIDDEN_SSID]);
 
-       params.privacy = !!info->attrs[NL80211_ATTR_PRIVACY];
+       params->privacy = !!info->attrs[NL80211_ATTR_PRIVACY];
 
        if (info->attrs[NL80211_ATTR_AUTH_TYPE]) {
-               params.auth_type = nla_get_u32(
+               params->auth_type = nla_get_u32(
                        info->attrs[NL80211_ATTR_AUTH_TYPE]);
-               if (!nl80211_valid_auth_type(rdev, params.auth_type,
-                                            NL80211_CMD_START_AP))
-                       return -EINVAL;
+               if (!nl80211_valid_auth_type(rdev, params->auth_type,
+                                            NL80211_CMD_START_AP)) {
+                       err = -EINVAL;
+                       goto out;
+               }
        } else
-               params.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
+               params->auth_type = NL80211_AUTHTYPE_AUTOMATIC;
 
-       err = nl80211_crypto_settings(rdev, info, &params.crypto,
+       err = nl80211_crypto_settings(rdev, info, &params->crypto,
                                      NL80211_MAX_NR_CIPHER_SUITES);
        if (err)
-               return err;
+               goto out;
 
        if (info->attrs[NL80211_ATTR_INACTIVITY_TIMEOUT]) {
-               if (!(rdev->wiphy.features & NL80211_FEATURE_INACTIVITY_TIMER))
-                       return -EOPNOTSUPP;
-               params.inactivity_timeout = nla_get_u16(
+               if (!(rdev->wiphy.features & NL80211_FEATURE_INACTIVITY_TIMER)) {
+                       err = -EOPNOTSUPP;
+                       goto out;
+               }
+               params->inactivity_timeout = nla_get_u16(
                        info->attrs[NL80211_ATTR_INACTIVITY_TIMEOUT]);
        }
 
        if (info->attrs[NL80211_ATTR_P2P_CTWINDOW]) {
-               if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
-                       return -EINVAL;
-               params.p2p_ctwindow =
+               if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) {
+                       err = -EINVAL;
+                       goto out;
+               }
+               params->p2p_ctwindow =
                        nla_get_u8(info->attrs[NL80211_ATTR_P2P_CTWINDOW]);
-               if (params.p2p_ctwindow != 0 &&
-                   !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_CTWIN))
-                       return -EINVAL;
+               if (params->p2p_ctwindow != 0 &&
+                   !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_CTWIN)) {
+                       err = -EINVAL;
+                       goto out;
+               }
        }
 
        if (info->attrs[NL80211_ATTR_P2P_OPPPS]) {
                u8 tmp;
 
-               if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
-                       return -EINVAL;
+               if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) {
+                       err = -EINVAL;
+                       goto out;
+               }
                tmp = nla_get_u8(info->attrs[NL80211_ATTR_P2P_OPPPS]);
-               params.p2p_opp_ps = tmp;
-               if (params.p2p_opp_ps != 0 &&
-                   !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_OPPPS))
-                       return -EINVAL;
+               params->p2p_opp_ps = tmp;
+               if (params->p2p_opp_ps != 0 &&
+                   !(rdev->wiphy.features & NL80211_FEATURE_P2P_GO_OPPPS)) {
+                       err = -EINVAL;
+                       goto out;
+               }
        }
 
        if (info->attrs[NL80211_ATTR_WIPHY_FREQ]) {
-               err = nl80211_parse_chandef(rdev, info, &params.chandef);
+               err = nl80211_parse_chandef(rdev, info, &params->chandef);
                if (err)
-                       return err;
+                       goto out;
        } else if (wdev->preset_chandef.chan) {
-               params.chandef = wdev->preset_chandef;
-       } else if (!nl80211_get_ap_channel(rdev, &params))
-               return -EINVAL;
+               params->chandef = wdev->preset_chandef;
+       } else if (!nl80211_get_ap_channel(rdev, params)) {
+               err = -EINVAL;
+               goto out;
+       }
 
-       if (!cfg80211_reg_can_beacon_relax(&rdev->wiphy, &params.chandef,
-                                          wdev->iftype))
-               return -EINVAL;
+       if (!cfg80211_reg_can_beacon_relax(&rdev->wiphy, &params->chandef,
+                                          wdev->iftype)) {
+               err = -EINVAL;
+               goto out;
+       }
 
        if (info->attrs[NL80211_ATTR_TX_RATES]) {
                err = nl80211_parse_tx_bitrate_mask(info, info->attrs,
                                                    NL80211_ATTR_TX_RATES,
-                                                   &params.beacon_rate,
+                                                   &params->beacon_rate,
                                                    dev, false);
                if (err)
-                       return err;
+                       goto out;
 
-               err = validate_beacon_tx_rate(rdev, params.chandef.chan->band,
-                                             &params.beacon_rate);
+               err = validate_beacon_tx_rate(rdev, params->chandef.chan->band,
+                                             &params->beacon_rate);
                if (err)
-                       return err;
+                       goto out;
        }
 
        if (info->attrs[NL80211_ATTR_SMPS_MODE]) {
-               params.smps_mode =
+               params->smps_mode =
                        nla_get_u8(info->attrs[NL80211_ATTR_SMPS_MODE]);
-               switch (params.smps_mode) {
+               switch (params->smps_mode) {
                case NL80211_SMPS_OFF:
                        break;
                case NL80211_SMPS_STATIC:
                        if (!(rdev->wiphy.features &
-                             NL80211_FEATURE_STATIC_SMPS))
-                               return -EINVAL;
+                             NL80211_FEATURE_STATIC_SMPS)) {
+                               err = -EINVAL;
+                               goto out;
+                       }
                        break;
                case NL80211_SMPS_DYNAMIC:
                        if (!(rdev->wiphy.features &
-                             NL80211_FEATURE_DYNAMIC_SMPS))
-                               return -EINVAL;
+                             NL80211_FEATURE_DYNAMIC_SMPS)) {
+                               err = -EINVAL;
+                               goto out;
+                       }
                        break;
                default:
-                       return -EINVAL;
+                       err = -EINVAL;
+                       goto out;
                }
        } else {
-               params.smps_mode = NL80211_SMPS_OFF;
+               params->smps_mode = NL80211_SMPS_OFF;
        }
 
-       params.pbss = nla_get_flag(info->attrs[NL80211_ATTR_PBSS]);
-       if (params.pbss && !rdev->wiphy.bands[NL80211_BAND_60GHZ])
-               return -EOPNOTSUPP;
+       params->pbss = nla_get_flag(info->attrs[NL80211_ATTR_PBSS]);
+       if (params->pbss && !rdev->wiphy.bands[NL80211_BAND_60GHZ]) {
+               err = -EOPNOTSUPP;
+               goto out;
+       }
 
        if (info->attrs[NL80211_ATTR_ACL_POLICY]) {
-               params.acl = parse_acl_data(&rdev->wiphy, info);
-               if (IS_ERR(params.acl))
-                       return PTR_ERR(params.acl);
+               params->acl = parse_acl_data(&rdev->wiphy, info);
+               if (IS_ERR(params->acl)) {
+                       err = PTR_ERR(params->acl);
+                       goto out;
+               }
        }
 
-       params.twt_responder =
+       params->twt_responder =
                    nla_get_flag(info->attrs[NL80211_ATTR_TWT_RESPONDER]);
 
        if (info->attrs[NL80211_ATTR_HE_OBSS_PD]) {
                err = nl80211_parse_he_obss_pd(
                                        info->attrs[NL80211_ATTR_HE_OBSS_PD],
-                                       &params.he_obss_pd);
+                                       &params->he_obss_pd);
                if (err)
                        goto out;
        }
@@ -5496,7 +5525,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
        if (info->attrs[NL80211_ATTR_HE_BSS_COLOR]) {
                err = nl80211_parse_he_bss_color(
                                        info->attrs[NL80211_ATTR_HE_BSS_COLOR],
-                                       &params.he_bss_color);
+                                       &params->he_bss_color);
                if (err)
                        goto out;
        }
@@ -5504,7 +5533,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
        if (info->attrs[NL80211_ATTR_FILS_DISCOVERY]) {
                err = nl80211_parse_fils_discovery(rdev,
                                                   info->attrs[NL80211_ATTR_FILS_DISCOVERY],
-                                                  &params);
+                                                  params);
                if (err)
                        goto out;
        }
@@ -5512,24 +5541,24 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
        if (info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP]) {
                err = nl80211_parse_unsol_bcast_probe_resp(
                        rdev, info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP],
-                       &params);
+                       params);
                if (err)
                        goto out;
        }
 
-       nl80211_calculate_ap_params(&params);
+       nl80211_calculate_ap_params(params);
 
        if (info->attrs[NL80211_ATTR_EXTERNAL_AUTH_SUPPORT])
-               params.flags |= AP_SETTINGS_EXTERNAL_AUTH_SUPPORT;
+               params->flags |= AP_SETTINGS_EXTERNAL_AUTH_SUPPORT;
 
        wdev_lock(wdev);
-       err = rdev_start_ap(rdev, dev, &params);
+       err = rdev_start_ap(rdev, dev, params);
        if (!err) {
-               wdev->preset_chandef = params.chandef;
-               wdev->beacon_interval = params.beacon_interval;
-               wdev->chandef = params.chandef;
-               wdev->ssid_len = params.ssid_len;
-               memcpy(wdev->ssid, params.ssid, wdev->ssid_len);
+               wdev->preset_chandef = params->chandef;
+               wdev->beacon_interval = params->beacon_interval;
+               wdev->chandef = params->chandef;
+               wdev->ssid_len = params->ssid_len;
+               memcpy(wdev->ssid, params->ssid, wdev->ssid_len);
 
                if (info->attrs[NL80211_ATTR_SOCKET_OWNER])
                        wdev->conn_owner_nlportid = info->snd_portid;
@@ -5537,7 +5566,8 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
        wdev_unlock(wdev);
 
 out:
-       kfree(params.acl);
+       kfree(params->acl);
+       kfree(params);
 
        return err;
 }