[PATCH] cfg80211: initialize on-stack chandefs

[PATCH] cfg80211: initialize on-stack chandefs

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

In a few places we don't properly initialize on-stack chandefs,
resulting in EDMG data to be non-zero, which broke things.

Additionally, in a few places we rely on the driver to init the
data completely, but perhaps we shouldn't as non-EDMG drivers
may not initialize the EDMG data, also initialize it there.

Fixes: 2a38075cd0be ("nl80211: Add support for EDMG channels")
Reported-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/wireless/nl80211.c     | 4 +++-
 net/wireless/reg.c         | 2 +-
 net/wireless/wext-compat.c | 2 +-
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d21b1581a665..b9797a3c110a 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2636,6 +2636,8 @@ int nl80211_parse_chandef(struct cfg80211_registered_device *rdev,
 
 	control_freq = nla_get_u32(attrs[NL80211_ATTR_WIPHY_FREQ]);
 
+	memset(chandef, 0, sizeof(*chandef));
+
 	chandef->chan = ieee80211_get_channel(&rdev->wiphy, control_freq);
 	chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
 	chandef->center_freq1 = control_freq;
@@ -3176,7 +3178,7 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 portid, u32 seq, int flag
 
 	if (rdev->ops->get_channel) {
 		int ret;
-		struct cfg80211_chan_def chandef;
+		struct cfg80211_chan_def chandef = {};
 
 		ret = rdev_get_channel(rdev, wdev, &chandef);
 		if (ret == 0) {
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 5311d0ae2454..420c4207ab59 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -2108,7 +2108,7 @@ static void reg_call_notifier(struct wiphy *wiphy,
 
 static bool reg_wdev_chan_valid(struct wiphy *wiphy, struct wireless_dev *wdev)
 {
-	struct cfg80211_chan_def chandef;
+	struct cfg80211_chan_def chandef = {};
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 	enum nl80211_iftype iftype;
 
diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 7b6529d81c61..cac9e28d852b 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -798,7 +798,7 @@ static int cfg80211_wext_giwfreq(struct net_device *dev,
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
-	struct cfg80211_chan_def chandef;
+	struct cfg80211_chan_def chandef = {};
 	int ret;
 
 	switch (wdev->iftype) {
-- 
2.20.1

Re: [PATCH] cfg80211: initialize on-stack chandefs

[Dmitry Osipenko]

23.09.2019 14:51, Johannes Berg пишет:
> From: Johannes Berg <johannes.berg@intel.com>
> 
> In a few places we don't properly initialize on-stack chandefs,
> resulting in EDMG data to be non-zero, which broke things.
> 
> Additionally, in a few places we rely on the driver to init the
> data completely, but perhaps we shouldn't as non-EDMG drivers
> may not initialize the EDMG data, also initialize it there.
> 
> Fixes: 2a38075cd0be ("nl80211: Add support for EDMG channels")
> Reported-by: Dmitry Osipenko <digetx@gmail.com>
> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
> ---
>  net/wireless/nl80211.c     | 4 +++-
>  net/wireless/reg.c         | 2 +-
>  net/wireless/wext-compat.c | 2 +-
>  3 files changed, 5 insertions(+), 3 deletions(-)

Johannes, thank you very much!

Tested-by: Dmitry Osipenko <digetx@gmail.com>

Re: [PATCH] cfg80211: initialize on-stack chandefs

[Johannes Berg]

On Mon, 2019-09-23 at 15:12 +0300, Dmitry Osipenko wrote:
> 
> Tested-by: Dmitry Osipenko <digetx@gmail.com>

That was quick, heh!

Thanks,
johannes

RE: [EXT] [PATCH] cfg80211: initialize on-stack chandefs

[Dedy Lansky]

From: Johannes Berg <johannes.berg@intel.com>
>
> ---
>  net/wireless/nl80211.c     | 4 +++-
>  net/wireless/reg.c         | 2 +-
>  net/wireless/wext-compat.c | 2 +-
>  3 files changed, 5 insertions(+), 3 deletions(-)

We planned to upload pretty much same fix today. You beat us on this.
We thought also to add memset in ieee80211_build_preq_ies()
(net/mac80211/util.c) but maybe this is not critical.

Thanks,
 Dedy.

Re: [PATCH] cfg80211: initialize on-stack chandefs

[Dmitry Osipenko]

23.09.2019 15:13, Johannes Berg пишет:
> On Mon, 2019-09-23 at 15:12 +0300, Dmitry Osipenko wrote:
>>
>> Tested-by: Dmitry Osipenko <digetx@gmail.com>
> 
> That was quick, heh!

Yes, it happened that I was doing some kernel work, had device to test
under my hand and checked email in the right time. Thanks again!