zd1211rw: Fix multicast filtering.

If multicast parameter (as returned by zd_op_prepare_multicast) has
changed, no bit in changed_flags is set. To handle this situation, we do
not return if changed_flags is 0. If we do so, we will have some issue
with IPv6 which uses multicast for link layer address resolution.

Signed-off-by: Benoit Papillault <benoit.papillault@free.fr>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/net/wireless/zd1211rw/zd_mac.c b/drivers/net/wireless/zd1211rw/zd_mac.c
index cc648efb8ed..9d9b263733e 100644
--- a/drivers/net/wireless/zd1211rw/zd_mac.c
+++ b/drivers/net/wireless/zd1211rw/zd_mac.c
@@ -987,12 +987,13 @@ static void zd_op_configure_filter(struct ieee80211_hw *hw,
         changed_flags &= SUPPORTED_FIF_FLAGS;
         *new_flags &= SUPPORTED_FIF_FLAGS;
 
-        /* changed_flags is always populated but this driver
-         * doesn't support all FIF flags so its possible we don't
-         * need to do anything */
-        if (!changed_flags)
-                return;
-
+        /*
+         * If multicast parameter (as returned by zd_op_prepare_multicast)
+         * has changed, no bit in changed_flags is set. To handle this
+         * situation, we do not return if changed_flags is 0. If we do so,
+         * we will have some issue with IPv6 which uses multicast for link
+         * layer address resolution.
+         */
         if (*new_flags & (FIF_PROMISC_IN_BSS | FIF_ALLMULTI))
                 zd_mc_add_all(&hash);