mac80211_hwsim: validate number of different channels

When creating a new radio on the fly, hwsim allows this to be done with an arbitrary number of channels, but cfg80211 only supports a limited number of simultaneous channels, leading to a warning. Fix this by validating the number - this requires moving the define for the maximum out to a visible header file. Reported-by: [email protected] Fixes: b59ec8d ("mac80211_hwsim: fix number of channels in interface combinations") Signed-off-by: Johannes Berg <[email protected]>
berg · Jan 15, 2018 · 51a1aaa · 51a1aaa
1 parent b71d856
commit 51a1aaa
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Showing 3 changed files with 7 additions and 2 deletions.
diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
@@ -3121,6 +3121,11 @@ static int hwsim_new_radio_nl(struct sk_buff *msg, struct genl_info *info)
 	if (info->attrs[HWSIM_ATTR_CHANNELS])
 		param.channels = nla_get_u32(info->attrs[HWSIM_ATTR_CHANNELS]);
 
+	if (param.channels > CFG80211_MAX_NUM_DIFFERENT_CHANNELS) {
+		GENL_SET_ERR_MSG(info, "too many channels specified");
+		return -EINVAL;
+	}
+
 	if (info->attrs[HWSIM_ATTR_NO_VIF])
 		param.no_vif = true;
 

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
@@ -815,6 +815,8 @@ struct cfg80211_csa_settings {
 	u8 count;
 };
 
+#define CFG80211_MAX_NUM_DIFFERENT_CHANNELS 10
+
 /**
  * struct iface_combination_params - input parameters for interface combinations
  *

diff --git a/net/wireless/core.h b/net/wireless/core.h
@@ -507,8 +507,6 @@ void cfg80211_stop_p2p_device(struct cfg80211_registered_device *rdev,
 void cfg80211_stop_nan(struct cfg80211_registered_device *rdev,
 		       struct wireless_dev *wdev);
 
-#define CFG80211_MAX_NUM_DIFFERENT_CHANNELS 10
-
 #ifdef CONFIG_CFG80211_DEVELOPER_WARNINGS
 #define CFG80211_DEV_WARN_ON(cond)	WARN_ON(cond)
 #else
-Original file line number
+Diff line change
@@ Expand Up / @@ -815,6 +815,8 @@ struct cfg80211_csa_settings { @@
     	u8 count;
     };
+    #define CFG80211_MAX_NUM_DIFFERENT_CHANNELS 10
     /**
      * struct iface_combination_params - input parameters for interface combinations
      *
@@ Expand Down @@