mac80211_hwsim: require at least one channel

[ Upstream commit 484004339d4514fde425f6e8a9f6a6cc979bb0c3 ]

Syzbot continues to try to create mac80211_hwsim radios, and
manages to pass parameters that are later checked with WARN_ON
in cfg80211 - catch another one in hwsim directly.

Reported-by: syzbot+2a12f11c306afe871c1f@syzkaller.appspotmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index d686ba10fecc1804bb00db48dcfc1c96eda1165f..62fcf57e22999cd097c210ce6bf759dea637e931 100644 (file)
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -3124,6 +3124,11 @@ 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 < 1) {
+               GENL_SET_ERR_MSG(info, "must have at least one channel");
+               return -EINVAL;
+       }
+
        if (param.channels > CFG80211_MAX_NUM_DIFFERENT_CHANNELS) {
                GENL_SET_ERR_MSG(info, "too many channels specified");
                return -EINVAL;