From ffa4629e0c2b8b015f5fa174149c6dd269b4142c Mon Sep 17 00:00:00 2001
From: Tova Mussai <tova.mussai@intel.com>
Date: Sat, 5 Aug 2017 11:44:38 +0300
Subject: [PATCH] nl80211: return error for invalid center_freq in 40 MHz
Git-commit: ffa4629e0c2b8b015f5fa174149c6dd269b4142c
Patch-mainline: v4.15-rc1
References: FATE#326294
When NL80211_ATTR_WIPHY_CHANNEL_TYPE is given, nl80211 would parse the
channel definition the old way, discarding NL80211_ATTR_CENTER_FREQ1,
NL80211_ATTR_CENTER_FREQ2 etc. However, it is possible that user space
added both NL80211_ATTR_WIPHY_CHANNEL_TYPE and NL80211_ATTR_CENTER_FREQ1
or NL80211_ATTR_CENTER_FREQ2 assuming that all settings would be honored.
In such a case, validate that NL80211_ATTR_CENTER_FREQ1 and
NL80211_ATTR_CENTER_FREQ2 values match the channel configuration,
as otherwise user space would assume that the desired configuration was
applied.
For example, when trying to start ap with
NL80211_ATTR_WIPHY_CHANNEL_TYPE = NL80211_CHAN_HT40MINUS,
NL80211_ATTR_WIPHY_FREQ = 5180 and NL80211_ATTR_CENTER_FREQ1 = 5250
without this fix, the ap will start on channel 36 (center_freq1 will be
corrected to 5180). With this fix, we will throw an error instead.
Signed-off-by: Tova Mussai <tova.mussai@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
net/wireless/nl80211.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 0df8023f480b..66e97136ab44 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2122,6 +2122,15 @@ static int nl80211_parse_chandef(struct cfg80211_registered_device *rdev,
case NL80211_CHAN_HT40MINUS:
cfg80211_chandef_create(chandef, chandef->chan,
chantype);
+ /* user input for center_freq is incorrect */
+ if (info->attrs[NL80211_ATTR_CENTER_FREQ1] &&
+ chandef->center_freq1 != nla_get_u32(
+ info->attrs[NL80211_ATTR_CENTER_FREQ1]))
+ return -EINVAL;
+ /* center_freq2 must be zero */
+ if (info->attrs[NL80211_ATTR_CENTER_FREQ2] &&
+ nla_get_u32(info->attrs[NL80211_ATTR_CENTER_FREQ2]))
+ return -EINVAL;
break;
default:
return -EINVAL;
--
2.19.2