mac80211_hwsim: check HWSIM_ATTR_RADIO_NAME length

Unfortunately, the nla policy was defined to have HWSIM_ATTR_RADIO_NAME
as an NLA_STRING, rather than NLA_NUL_STRING, so we can't use it as a
NUL-terminated string in the kernel.

Rather than break the API, kasprintf() the string to a new buffer to
guarantee NUL termination.

Reported-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2017-02-27 17:15:28 +01:00
Родитель 09e0a2fe10
Коммит ff4dd73dd2
1 изменённых файлов: 21 добавлений и 7 удалений

Просмотреть файл

@ -3056,6 +3056,7 @@ static int hwsim_register_received_nl(struct sk_buff *skb_2,
static int hwsim_new_radio_nl(struct sk_buff *msg, struct genl_info *info)
{
struct hwsim_new_radio_params param = { 0 };
const char *hwname = NULL;
param.reg_strict = info->attrs[HWSIM_ATTR_REG_STRICT_REG];
param.p2p_device = info->attrs[HWSIM_ATTR_SUPPORT_P2P_DEVICE];
@ -3069,8 +3070,14 @@ static int hwsim_new_radio_nl(struct sk_buff *msg, struct genl_info *info)
if (info->attrs[HWSIM_ATTR_NO_VIF])
param.no_vif = true;
if (info->attrs[HWSIM_ATTR_RADIO_NAME])
param.hwname = nla_data(info->attrs[HWSIM_ATTR_RADIO_NAME]);
if (info->attrs[HWSIM_ATTR_RADIO_NAME]) {
hwname = kasprintf(GFP_KERNEL, "%.*s",
nla_len(info->attrs[HWSIM_ATTR_RADIO_NAME]),
(char *)nla_data(info->attrs[HWSIM_ATTR_RADIO_NAME]));
if (!hwname)
return -ENOMEM;
param.hwname = hwname;
}
if (info->attrs[HWSIM_ATTR_USE_CHANCTX])
param.use_chanctx = true;
@ -3098,11 +3105,15 @@ static int hwsim_del_radio_nl(struct sk_buff *msg, struct genl_info *info)
s64 idx = -1;
const char *hwname = NULL;
if (info->attrs[HWSIM_ATTR_RADIO_ID])
if (info->attrs[HWSIM_ATTR_RADIO_ID]) {
idx = nla_get_u32(info->attrs[HWSIM_ATTR_RADIO_ID]);
else if (info->attrs[HWSIM_ATTR_RADIO_NAME])
hwname = (void *)nla_data(info->attrs[HWSIM_ATTR_RADIO_NAME]);
else
} else if (info->attrs[HWSIM_ATTR_RADIO_NAME]) {
hwname = kasprintf(GFP_KERNEL, "%.*s",
nla_len(info->attrs[HWSIM_ATTR_RADIO_NAME]),
(char *)nla_data(info->attrs[HWSIM_ATTR_RADIO_NAME]));
if (!hwname)
return -ENOMEM;
} else
return -EINVAL;
spin_lock_bh(&hwsim_radio_lock);
@ -3111,7 +3122,8 @@ static int hwsim_del_radio_nl(struct sk_buff *msg, struct genl_info *info)
if (data->idx != idx)
continue;
} else {
if (strcmp(hwname, wiphy_name(data->hw->wiphy)))
if (!hwname ||
strcmp(hwname, wiphy_name(data->hw->wiphy)))
continue;
}
@ -3122,10 +3134,12 @@ static int hwsim_del_radio_nl(struct sk_buff *msg, struct genl_info *info)
spin_unlock_bh(&hwsim_radio_lock);
mac80211_hwsim_del_radio(data, wiphy_name(data->hw->wiphy),
info);
kfree(hwname);
return 0;
}
spin_unlock_bh(&hwsim_radio_lock);
kfree(hwname);
return -ENODEV;
}