diff options
Diffstat (limited to 'net/mac80211/util.c')
| -rw-r--r-- | net/mac80211/util.c | 34 |
1 files changed, 27 insertions, 7 deletions
diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 6e4c8bd5bfee..f119b1b6c1a7 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -1107,12 +1107,12 @@ void ieee80211_send_deauth_disassoc(struct ieee80211_sub_if_data *sdata, } int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, - const u8 *ie, size_t ie_len, + size_t buffer_len, const u8 *ie, size_t ie_len, enum ieee80211_band band, u32 rate_mask, u8 channel) { struct ieee80211_supported_band *sband; - u8 *pos; + u8 *pos = buffer, *end = buffer + buffer_len; size_t offset = 0, noffset; int supp_rates_len, i; u8 rates[32]; @@ -1123,8 +1123,6 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, if (WARN_ON_ONCE(!sband)) return 0; - pos = buffer; - num_rates = 0; for (i = 0; i < sband->n_bitrates; i++) { if ((BIT(i) & rate_mask) == 0) @@ -1134,6 +1132,8 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, supp_rates_len = min_t(int, num_rates, 8); + if (end - pos < 2 + supp_rates_len) + goto out_err; *pos++ = WLAN_EID_SUPP_RATES; *pos++ = supp_rates_len; memcpy(pos, rates, supp_rates_len); @@ -1150,6 +1150,8 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, before_extrates, ARRAY_SIZE(before_extrates), offset); + if (end - pos < noffset - offset) + goto out_err; memcpy(pos, ie + offset, noffset - offset); pos += noffset - offset; offset = noffset; @@ -1157,6 +1159,8 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, ext_rates_len = num_rates - supp_rates_len; if (ext_rates_len > 0) { + if (end - pos < 2 + ext_rates_len) + goto out_err; *pos++ = WLAN_EID_EXT_SUPP_RATES; *pos++ = ext_rates_len; memcpy(pos, rates + supp_rates_len, ext_rates_len); @@ -1164,6 +1168,8 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, } if (channel && sband->band == IEEE80211_BAND_2GHZ) { + if (end - pos < 3) + goto out_err; *pos++ = WLAN_EID_DS_PARAMS; *pos++ = 1; *pos++ = channel; @@ -1182,14 +1188,19 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, noffset = ieee80211_ie_split(ie, ie_len, before_ht, ARRAY_SIZE(before_ht), offset); + if (end - pos < noffset - offset) + goto out_err; memcpy(pos, ie + offset, noffset - offset); pos += noffset - offset; offset = noffset; } - if (sband->ht_cap.ht_supported) + if (sband->ht_cap.ht_supported) { + if (end - pos < 2 + sizeof(struct ieee80211_ht_cap)) + goto out_err; pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap); + } /* * If adding more here, adjust code in main.c @@ -1199,15 +1210,23 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, /* add any remaining custom IEs */ if (ie && ie_len) { noffset = ie_len; + if (end - pos < noffset - offset) + goto out_err; memcpy(pos, ie + offset, noffset - offset); pos += noffset - offset; } - if (sband->vht_cap.vht_supported) + if (sband->vht_cap.vht_supported) { + if (end - pos < 2 + sizeof(struct ieee80211_vht_cap)) + goto out_err; pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap); + } return pos - buffer; + out_err: + WARN_ONCE(1, "not enough space for preq IEs\n"); + return pos - buffer; } struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata, @@ -1239,7 +1258,8 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata, else chan_no = ieee80211_frequency_to_channel(chan->center_freq); - buf_len = ieee80211_build_preq_ies(local, buf, ie, ie_len, chan->band, + buf_len = ieee80211_build_preq_ies(local, buf, 200 + ie_len, + ie, ie_len, chan->band, ratemask, chan_no); skb = ieee80211_probereq_get(&local->hw, &sdata->vif, |