wireless: restrict to 32 legacy rates

Since the standards only define 12 legacy rates, 32 is certainly
a sane upper limit and we don't need to use u64 everywhere. Add
sanity checking that no more than 32 rates are registered and
change the variables to u32 throughout.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/net/wireless/core.c b/net/wireless/core.c
index b96fc0c3f1c4..125226476089 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -273,10 +273,16 @@ int wiphy_register(struct wiphy *wiphy)
 
                 sband->band = band;
 
-                if (!sband->n_channels || !sband->n_bitrates) {
-                        WARN_ON(1);
+                if (WARN_ON(!sband->n_channels || !sband->n_bitrates))
+                        return -EINVAL;
+
+                /*
+                 * Since we use a u32 for rate bitmaps in
+                 * ieee80211_get_response_rate, we cannot
+                 * have more than 32 legacy rates.
+                 */
+                if (WARN_ON(sband->n_bitrates > 32))
                         return -EINVAL;
-                }
 
                 for (i = 0; i < sband->n_channels; i++) {
                         sband->channels[i].orig_flags =