diff options
| -rw-r--r-- | net/wireless/scan.c | 213 |
1 files changed, 124 insertions, 89 deletions
diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 2212e6d24204..b9eb91f485f8 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -259,117 +259,152 @@ bool cfg80211_is_element_inherited(const struct element *elem, } EXPORT_SYMBOL(cfg80211_is_element_inherited); -static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, - const u8 *subelement, size_t subie_len, - u8 *new_ie, gfp_t gfp) +static size_t cfg80211_copy_elem_with_frags(const struct element *elem, + const u8 *ie, size_t ie_len, + u8 **pos, u8 *buf, size_t buf_len) { - u8 *pos, *tmp; - const u8 *tmp_old, *tmp_new; - const struct element *non_inherit_elem; - u8 *sub_copy; + if (WARN_ON((u8 *)elem < ie || elem->data > ie + ie_len || + elem->data + elem->datalen > ie + ie_len)) + return 0; - /* copy subelement as we need to change its content to - * mark an ie after it is processed. - */ - sub_copy = kmemdup(subelement, subie_len, gfp); - if (!sub_copy) + if (elem->datalen + 2 > buf + buf_len - *pos) return 0; - pos = &new_ie[0]; + memcpy(*pos, elem, elem->datalen + 2); + *pos += elem->datalen + 2; - /* set new ssid */ - tmp_new = cfg80211_find_ie(WLAN_EID_SSID, sub_copy, subie_len); - if (tmp_new) { - memcpy(pos, tmp_new, tmp_new[1] + 2); - pos += (tmp_new[1] + 2); + /* Finish if it is not fragmented */ + if (elem->datalen != 255) + return *pos - buf; + + ie_len = ie + ie_len - elem->data - elem->datalen; + ie = (const u8 *)elem->data + elem->datalen; + + for_each_element(elem, ie, ie_len) { + if (elem->id != WLAN_EID_FRAGMENT) + break; + + if (elem->datalen + 2 > buf + buf_len - *pos) + return 0; + + memcpy(*pos, elem, elem->datalen + 2); + *pos += elem->datalen + 2; + + if (elem->datalen != 255) + break; } - /* get non inheritance list if exists */ - non_inherit_elem = - cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, - sub_copy, subie_len); + return *pos - buf; +} - /* go through IEs in ie (skip SSID) and subelement, - * merge them into new_ie +static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, + const u8 *subie, size_t subie_len, + u8 *new_ie, size_t new_ie_len) +{ + const struct element *non_inherit_elem, *parent, *sub; + u8 *pos = new_ie; + u8 id, ext_id; + unsigned int match_len; + + non_inherit_elem = cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, + subie, subie_len); + + /* We copy the elements one by one from the parent to the generated + * elements. + * If they are not inherited (included in subie or in the non + * inheritance element), then we copy all occurrences the first time + * we see this element type. */ - tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen); - tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie; - - while (tmp_old + 2 - ie <= ielen && - tmp_old + tmp_old[1] + 2 - ie <= ielen) { - if (tmp_old[0] == 0) { - tmp_old++; + for_each_element(parent, ie, ielen) { + if (parent->id == WLAN_EID_FRAGMENT) continue; + + if (parent->id == WLAN_EID_EXTENSION) { + if (parent->datalen < 1) + continue; + + id = WLAN_EID_EXTENSION; + ext_id = parent->data[0]; + match_len = 1; + } else { + id = parent->id; + match_len = 0; } - if (tmp_old[0] == WLAN_EID_EXTENSION) - tmp = (u8 *)cfg80211_find_ext_ie(tmp_old[2], sub_copy, - subie_len); - else - tmp = (u8 *)cfg80211_find_ie(tmp_old[0], sub_copy, - subie_len); + /* Find first occurrence in subie */ + sub = cfg80211_find_elem_match(id, subie, subie_len, + &ext_id, match_len, 0); - if (!tmp) { - const struct element *old_elem = (void *)tmp_old; + /* Copy from parent if not in subie and inherited */ + if (!sub && + cfg80211_is_element_inherited(parent, non_inherit_elem)) { + if (!cfg80211_copy_elem_with_frags(parent, + ie, ielen, + &pos, new_ie, + new_ie_len)) + return 0; - /* ie in old ie but not in subelement */ - if (cfg80211_is_element_inherited(old_elem, - non_inherit_elem)) { - memcpy(pos, tmp_old, tmp_old[1] + 2); - pos += tmp_old[1] + 2; - } - } else { - /* ie in transmitting ie also in subelement, - * copy from subelement and flag the ie in subelement - * as copied (by setting eid field to WLAN_EID_SSID, - * which is skipped anyway). - * For vendor ie, compare OUI + type + subType to - * determine if they are the same ie. - */ - if (tmp_old[0] == WLAN_EID_VENDOR_SPECIFIC) { - if (tmp_old[1] >= 5 && tmp[1] >= 5 && - !memcmp(tmp_old + 2, tmp + 2, 5)) { - /* same vendor ie, copy from - * subelement - */ - memcpy(pos, tmp, tmp[1] + 2); - pos += tmp[1] + 2; - tmp[0] = WLAN_EID_SSID; - } else { - memcpy(pos, tmp_old, tmp_old[1] + 2); - pos += tmp_old[1] + 2; - } - } else { - /* copy ie from subelement into new ie */ - memcpy(pos, tmp, tmp[1] + 2); - pos += tmp[1] + 2; - tmp[0] = WLAN_EID_SSID; - } + continue; } - if (tmp_old + tmp_old[1] + 2 - ie == ielen) - break; + /* Already copied if an earlier element had the same type */ + if (cfg80211_find_elem_match(id, ie, (u8 *)parent - ie, + &ext_id, match_len, 0)) + continue; - tmp_old += tmp_old[1] + 2; + /* Not inheriting, copy all similar elements from subie */ + while (sub) { + if (!cfg80211_copy_elem_with_frags(sub, + subie, subie_len, + &pos, new_ie, + new_ie_len)) + return 0; + + sub = cfg80211_find_elem_match(id, + sub->data + sub->datalen, + subie_len + subie - + (sub->data + + sub->datalen), + &ext_id, match_len, 0); + } } - /* go through subelement again to check if there is any ie not - * copied to new ie, skip ssid, capability, bssid-index ie + /* The above misses elements that are included in subie but not in the + * parent, so do a pass over subie and append those. + * Skip the non-tx BSSID caps and non-inheritance element. */ - tmp_new = sub_copy; - while (tmp_new + 2 - sub_copy <= subie_len && - tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) { - if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP || - tmp_new[0] == WLAN_EID_SSID)) { - memcpy(pos, tmp_new, tmp_new[1] + 2); - pos += tmp_new[1] + 2; + for_each_element(sub, subie, subie_len) { + if (sub->id == WLAN_EID_NON_TX_BSSID_CAP) + continue; + + if (sub->id == WLAN_EID_FRAGMENT) + continue; + + if (sub->id == WLAN_EID_EXTENSION) { + if (sub->datalen < 1) + continue; + + id = WLAN_EID_EXTENSION; + ext_id = sub->data[0]; + match_len = 1; + + if (ext_id == WLAN_EID_EXT_NON_INHERITANCE) + continue; + } else { + id = sub->id; + match_len = 0; } - if (tmp_new + tmp_new[1] + 2 - sub_copy == subie_len) - break; - tmp_new += tmp_new[1] + 2; + + /* Processed if one was included in the parent */ + if (cfg80211_find_elem_match(id, ie, ielen, + &ext_id, match_len, 0)) + continue; + + if (!cfg80211_copy_elem_with_frags(sub, subie, subie_len, + &pos, new_ie, new_ie_len)) + return 0; } - kfree(sub_copy); return pos - new_ie; } @@ -2228,7 +2263,7 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, new_ie_len = cfg80211_gen_new_ie(ie, ielen, profile, profile_len, new_ie, - gfp); + IEEE80211_MAX_DATA_LEN); if (!new_ie_len) continue; |