cfg80211: validate remain-on-channel time better
The remain-on-channel time validation shouldn't
depend on the value of HZ, as it does now with
the check against jiffies, since then you might
use a value that works on one system but not on
another. Fix it by checking against a minimum
that's fixed.
Also add validation of the wait duration for a
management frame TX since this also translates
into remain-on-channel internally.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 85e5037..970afdf 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -1522,6 +1522,8 @@
#define NL80211_MAX_NR_CIPHER_SUITES 5
#define NL80211_MAX_NR_AKM_SUITES 2
+#define NL80211_MIN_REMAIN_ON_CHANNEL_TIME 10
+
/**
* enum nl80211_iftype - (virtual) interface types
*
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 5e29bd3..7ae54b8 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5545,18 +5545,18 @@
duration = nla_get_u32(info->attrs[NL80211_ATTR_DURATION]);
- /*
- * We should be on that channel for at least one jiffie,
- * and more than 5 seconds seems excessive.
- */
- if (!duration || !msecs_to_jiffies(duration) ||
- duration > rdev->wiphy.max_remain_on_channel_duration)
- return -EINVAL;
-
if (!rdev->ops->remain_on_channel ||
!(rdev->wiphy.flags & WIPHY_FLAG_HAS_REMAIN_ON_CHANNEL))
return -EOPNOTSUPP;
+ /*
+ * We should be on that channel for at least a minimum amount of
+ * time (10ms) but no longer than the driver supports.
+ */
+ if (duration < NL80211_MIN_REMAIN_ON_CHANNEL_TIME ||
+ duration > rdev->wiphy.max_remain_on_channel_duration)
+ return -EINVAL;
+
if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE] &&
!nl80211_valid_channel_type(info, &channel_type))
return -EINVAL;
@@ -5827,6 +5827,15 @@
if (!(rdev->wiphy.flags & WIPHY_FLAG_OFFCHAN_TX))
return -EINVAL;
wait = nla_get_u32(info->attrs[NL80211_ATTR_DURATION]);
+
+ /*
+ * We should wait on the channel for at least a minimum amount
+ * of time (10ms) but no longer than the driver supports.
+ */
+ if (wait < NL80211_MIN_REMAIN_ON_CHANNEL_TIME ||
+ wait > rdev->wiphy.max_remain_on_channel_duration)
+ return -EINVAL;
+
}
if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) {