[PATCH] cfg80211: Use the correct IE buffer pointer

[PATCH] cfg80211: Use the correct IE buffer pointer

[Michael Buesch]

If the IE buffer was allocated, the pub.information_elements pointer
was also changed to the allocated space. So we must not assume anymore
that the pointer points at the "found" tail.

So if it was allocated previously, take the codebranch that grows the
buffer size (if necessary) and put the data into the allocated buffer.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Acked-by: Johannes Berg <johannes@sipsolutions.net>

---

The original code will probably not overrun the buffer, because the buffer is always
guaranteed to be bigger than ksize(found)-used. But I think it's a bad idea anyway to poke with
a dangling pointer. ;)


 net/wireless/scan.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- wireless-testing.orig/net/wireless/scan.c
+++ wireless-testing/net/wireless/scan.c
@@ -377,7 +377,7 @@ cfg80211_bss_update(struct cfg80211_regi
 			size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 			size_t ielen = res->pub.len_information_elements;
 
-			if (ksize(found) >= used + ielen) {
+			if (!found->ies_allocated && ksize(found) >= used + ielen) {
 				memcpy(found->pub.information_elements,
 				       res->pub.information_elements, ielen);
 				found->pub.len_information_elements = ielen;


-- 
Greetings, Michael.