From 1c8745f3ec6f46f5fa99dbcdf92381144ae1b37f Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 7 Feb 2019 22:36:33 +0100 Subject: [PATCH] cfg80211: use for_each_element() for multi-bssid parsing Use the new for_each_element() helper here, we cannot use for_each_subelement() since we have a fixed 1 byte before the subelements start. While at it, also fix le16_to_cpup() to be get_unaligned_le16() since we don't know anything about alignment. Signed-off-by: Johannes Berg --- net/wireless/scan.c | 47 +++++++++++++++-------------------------------- 1 file changed, 15 insertions(+), 32 deletions(-) diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 531c2e5..54feb77 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1377,9 +1377,9 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, struct cfg80211_bss *trans_bss, gfp_t gfp) { - const u8 *pos, *subelement, *mbssid_end_pos; - const u8 *tmp, *mbssid_index_ie; - size_t subie_len, new_ie_len; + const u8 *mbssid_index_ie; + const struct element *elem, *sub; + size_t new_ie_len; u8 new_bssid[ETH_ALEN]; u8 *new_ie; u16 capability; @@ -1390,34 +1390,21 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, if (!cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, ie, ielen)) return; - pos = ie; - new_ie = kmalloc(IEEE80211_MAX_DATA_LEN, gfp); if (!new_ie) return; - while (pos < ie + ielen + 2) { - tmp = cfg80211_find_ie(WLAN_EID_MULTIPLE_BSSID, pos, - ielen - (pos - ie)); - if (!tmp) - break; - - mbssid_end_pos = tmp + tmp[1] + 2; - /* Skip Element ID, Len, MaxBSSID Indicator */ - if (tmp[1] < 4) - break; - for (subelement = tmp + 3; subelement < mbssid_end_pos - 1; - subelement += 2 + subelement[1]) { - subie_len = subelement[1]; - if (mbssid_end_pos - subelement < 2 + subie_len) - break; - if (subelement[0] != 0 || subelement[1] < 4) { + for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) { + if (elem->datalen < 4) + continue; + for_each_element(sub, elem->data + 1, elem->datalen - 1) { + if (sub->id != 0 || sub->datalen < 4) { /* not a valid BSS profile */ continue; } - if (subelement[2] != WLAN_EID_NON_TX_BSSID_CAP || - subelement[3] != 2) { + if (sub->data[0] != WLAN_EID_NON_TX_BSSID_CAP || + sub->data[1] != 2) { /* The first element within the Nontransmitted * BSSID Profile is not the Nontransmitted * BSSID Capability element. @@ -1428,26 +1415,24 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, /* found a Nontransmitted BSSID Profile */ mbssid_index_ie = cfg80211_find_ie (WLAN_EID_MULTI_BSSID_IDX, - subelement + 2, subie_len); + sub->data, sub->datalen); if (!mbssid_index_ie || mbssid_index_ie[1] < 1 || mbssid_index_ie[2] == 0) { /* No valid Multiple BSSID-Index element */ continue; } - cfg80211_gen_new_bssid(bssid, tmp[2], + cfg80211_gen_new_bssid(bssid, elem->data[0], mbssid_index_ie[2], new_bssid); memset(new_ie, 0, IEEE80211_MAX_DATA_LEN); - new_ie_len = cfg80211_gen_new_ie(ie, ielen, - subelement + 2, - subie_len, new_ie, + new_ie_len = cfg80211_gen_new_ie(ie, ielen, sub->data, + sub->datalen, new_ie, gfp); if (!new_ie_len) continue; - capability = le16_to_cpup((const __le16 *) - &subelement[4]); + capability = get_unaligned_le16(sub->data + 2); bss = cfg80211_inform_single_bss_data(wiphy, data, ftype, new_bssid, tsf, @@ -1460,8 +1445,6 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, break; cfg80211_put_bss(wiphy, bss); } - - pos = mbssid_end_pos; } kfree(new_ie); -- 2.7.4