From ebf348fcd088e3ffc6e76f6f349e27d30604865b Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 1 Jun 2012 12:50:54 +0200 Subject: [PATCH] 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 Signed-off-by: John W. Linville --- include/linux/nl80211.h | 2 ++ net/wireless/nl80211.c | 23 ++++++++++++++++------- 2 files changed, 18 insertions(+), 7 deletions(-) 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 @@ enum nl80211_attrs { #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 @@ static int nl80211_remain_on_channel(struct sk_buff *skb, duration = nla_get_u32(info->attrs[NL80211_ATTR_DURATION]); + 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 one jiffie, - * and more than 5 seconds seems excessive. + * We should be on that channel for at least a minimum amount of + * time (10ms) but no longer than the driver supports. */ - if (!duration || !msecs_to_jiffies(duration) || + if (duration < NL80211_MIN_REMAIN_ON_CHANNEL_TIME || 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; - if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE] && !nl80211_valid_channel_type(info, &channel_type)) return -EINVAL; @@ -5827,6 +5827,15 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) 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]) { -- 2.7.4