cfg80211: do not replace BSS structs
Instead, allocate extra IE memory if necessary. Normally,
this isn't even necessary since there's enough space.
This is a better way of correcting the "held BSS can
disappear" issue, but also a lot more code. It is also
necessary for proper auth/assoc BSS handling in the
future.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 4c77669..2ae65b3 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -58,6 +58,10 @@
bss = container_of(ref, struct cfg80211_internal_bss, ref);
if (bss->pub.free_priv)
bss->pub.free_priv(&bss->pub);
+
+ if (bss->ies_allocated)
+ kfree(bss->pub.information_elements);
+
kfree(bss);
}
@@ -360,21 +364,41 @@
found = rb_find_bss(dev, res);
- if (found && overwrite) {
- list_replace(&found->list, &res->list);
- rb_replace_node(&found->rbn, &res->rbn,
- &dev->bss_tree);
- /* XXX: workaround */
- res->hold = found->hold;
- kref_put(&found->ref, bss_release);
- found = res;
- } else if (found) {
+ if (found) {
kref_get(&found->ref);
found->pub.beacon_interval = res->pub.beacon_interval;
found->pub.tsf = res->pub.tsf;
found->pub.signal = res->pub.signal;
found->pub.capability = res->pub.capability;
found->ts = res->ts;
+
+ /* overwrite IEs */
+ if (overwrite) {
+ size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
+ size_t ielen = res->pub.len_information_elements;
+
+ if (ksize(found) >= used + ielen) {
+ memcpy(found->pub.information_elements,
+ res->pub.information_elements, ielen);
+ found->pub.len_information_elements = ielen;
+ } else {
+ u8 *ies = found->pub.information_elements;
+
+ if (found->ies_allocated) {
+ if (ksize(ies) < ielen)
+ ies = krealloc(ies, ielen,
+ GFP_ATOMIC);
+ } else
+ ies = kmalloc(ielen, GFP_ATOMIC);
+
+ if (ies) {
+ memcpy(ies, res->pub.information_elements, ielen);
+ found->ies_allocated = true;
+ found->pub.information_elements = ies;
+ }
+ }
+ }
+
kref_put(&res->ref, bss_release);
} else {
/* this "consumes" the reference */