[PATCH 5.17 147/158] nl80211: fix locking in nl80211_set_tx_bitrate_mask()

Greg Kroah-Hartman
2022-05-23T18:09:00Z

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

[ Upstream commit f971e1887fdb3ab500c9bebf4b98f62d49a20655 ]

This accesses the wdev's chandef etc., so cannot safely
be used without holding the lock.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20220506102136.06b7205419e6.I2a87c05fbd8bc5e565e84d190d4cfd2e92695a90@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/wireless/nl80211.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 06a35f1bec23..0c20df052db3 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -11573,18 +11573,23 @@ static int nl80211_set_tx_bitrate_mask(struct sk_buff *skb,
struct cfg80211_bitrate_mask mask;
struct cfg80211_registered_device *rdev = info->user_ptr[0];
struct net_device *dev = info->user_ptr[1];
+ struct wireless_dev *wdev = dev->ieee80211_ptr;
int err;

if (!rdev->ops->set_bitrate_mask)
return -EOPNOTSUPP;

+ wdev_lock(wdev);
err = nl80211_parse_tx_bitrate_mask(info, info->attrs,
NL80211_ATTR_TX_RATES, &mask,
dev, true);
if (err)
- return err;
+ goto out;

- return rdev_set_bitrate_mask(rdev, dev, NULL, &mask);
+ err = rdev_set_bitrate_mask(rdev, dev, NULL, &mask);
+out:
+ wdev_unlock(wdev);
+ return err;
}

static int nl80211_register_mgmt(struct sk_buff *skb, struct genl_info *info)
--
2.35.1