cfg80211: handle fragmented IEs in splitting
The IEs "output" can sometimes combine IEs coming from userspace
with IEs generated in the kernel - in particular mac80211 does
this for association frames.
Add support in this code for the 802.11 IE fragmentation.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/util.c b/net/wireless/util.c
index 7681b65..32060f8 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1382,6 +1382,25 @@
return false;
}
+static size_t skip_ie(const u8 *ies, size_t ielen, size_t pos)
+{
+ /* we assume a validly formed IEs buffer */
+ u8 len = ies[pos + 1];
+
+ pos += 2 + len;
+
+ /* the IE itself must have 255 bytes for fragments to follow */
+ if (len < 255)
+ return pos;
+
+ while (pos < ielen && ies[pos] == WLAN_EID_FRAGMENT) {
+ len = ies[pos + 1];
+ pos += 2 + len;
+ }
+
+ return pos;
+}
+
size_t ieee80211_ie_split_ric(const u8 *ies, size_t ielen,
const u8 *ids, int n_ids,
const u8 *after_ric, int n_after_ric,
@@ -1391,14 +1410,14 @@
while (pos < ielen && ieee80211_id_in_list(ids, n_ids, ies[pos])) {
if (ies[pos] == WLAN_EID_RIC_DATA && n_after_ric) {
- pos += 2 + ies[pos + 1];
+ pos = skip_ie(ies, ielen, pos);
while (pos < ielen &&
!ieee80211_id_in_list(after_ric, n_after_ric,
ies[pos]))
- pos += 2 + ies[pos + 1];
+ pos = skip_ie(ies, ielen, pos);
} else {
- pos += 2 + ies[pos + 1];
+ pos = skip_ie(ies, ielen, pos);
}
}