Return-path: Received: from mga03.intel.com ([143.182.124.21]:12816 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750799Ab2D3HYv (ORCPT ); Mon, 30 Apr 2012 03:24:51 -0400 From: Emmanuel Grumbach To: linux-wireless@vger.kernel.org Cc: Emmanuel Grumbach , Felix Fietkau Subject: [PATCH v2] cfg80211: fix BSS comparison Date: Mon, 30 Apr 2012 10:23:36 +0300 Message-Id: <1335770616-12695-1-git-send-email-emmanuel.grumbach@intel.com> (sfid-20120430_092457_844804_47B25CF9) Content-Type: text/plain; charset="us-ascii" Sender: linux-wireless-owner@vger.kernel.org List-ID: Since the BSS table is organized in a RB tree, the BSSs need to be comparable. This means that we must define a < and > operator to the BSS object. compare_ethr_addr isn't enough since it returns only a binary value. Since Felix's cfg80211: use compare_ether_addr on MAC addresses instead of memcmp Because of the constant size and guaranteed 16 bit alignment, the inline compare_ether_addr function is much cheaper than calling memcmp. Signed-off-by: Felix Fietkau Signed-off-by: John W. Linville The BSS table is corrupted: rb_find_bss can't find the bss. As a result BSSes are duplicated in the BSS table, and we get stuck while probing an AP before associating (in STA mode). Change-Id: I85928756f4328028230832c1565ece7f412f3843 CC: Felix Fietkau Signed-off-by: Emmanuel Grumbach --- v2: add a comment to warn the next guy that will try to over optimize :-) --- net/wireless/scan.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/net/wireless/scan.c b/net/wireless/scan.c index bd6a0ee..aa01335 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -378,7 +378,11 @@ static int cmp_bss_core(struct cfg80211_bss *a, b->len_information_elements); } - return compare_ether_addr(a->bssid, b->bssid); + /* + * we can't use compare_ether_addr here since we need a < > operator. + * The binary return value of compare_ether_addr isn't enough + */ + return memcmp(a->bssid, b->bssid, sizeof(a->bssid)); } static int cmp_bss(struct cfg80211_bss *a, -- 1.7.1 --------------------------------------------------------------------- Intel Israel (74) Limited This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.