From: Johannes Berg <johannes.berg@xxxxxxxxx>
Instead of open-coding a lot of calls to is_valid_ie_attr(),
add this validation directly to the policy, now that we can.
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
---
net/wireless/nl80211.c | 122 +++++++++++++++++++------------------------------
1 file changed, 46 insertions(+), 76 deletions(-)
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d894f78e6b0a..36e26ac20638 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -200,6 +200,36 @@ cfg80211_get_dev_from_info(struct net *netns, struct genl_info *info)
return __cfg80211_rdev_from_attrs(netns, info->attrs);
}
+static int validate_ie_attr(const struct nlattr *attr,
+ struct netlink_ext_ack *extack)
+{
+ const u8 *pos;
+ int len;
+
+ pos = nla_data(attr);
+ len = nla_len(attr);
+
+ while (len) {
+ u8 elemlen;
+
+ if (len < 2)
+ goto error;
+ len -= 2;
+
+ elemlen = pos[1];
+ if (elemlen > len)
+ goto error;
+
+ len -= elemlen;
+ pos += 2 + elemlen;
+ }
+
+ return 0;
+error:
+ NL_SET_ERR_MSG_ATTR(extack, attr, "malformed information elements");
+ return -EINVAL;
+}
+
/* policy for the attributes */
static const struct nla_policy
nl80211_ftm_responder_policy[NL80211_FTM_RESP_ATTR_MAX + 1] = {
@@ -250,8 +280,9 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
[NL80211_ATTR_DTIM_PERIOD] = { .type = NLA_U32 },
[NL80211_ATTR_BEACON_HEAD] = { .type = NLA_BINARY,
.len = IEEE80211_MAX_DATA_LEN },
- [NL80211_ATTR_BEACON_TAIL] = { .type = NLA_BINARY,
- .len = IEEE80211_MAX_DATA_LEN },
+ [NL80211_ATTR_BEACON_TAIL] =
+ NLA_POLICY_VALIDATE_FN(NLA_BINARY, validate_ie_attr,
+ IEEE80211_MAX_DATA_LEN),
[NL80211_ATTR_STA_AID] =
NLA_POLICY_RANGE(NLA_U16, 1, IEEE80211_MAX_AID),
[NL80211_ATTR_STA_FLAGS] = { .type = NLA_NESTED },
@@ -282,8 +313,9 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
[NL80211_ATTR_HT_CAPABILITY] = { .len = NL80211_HT_CAPABILITY_LEN },
[NL80211_ATTR_MGMT_SUBTYPE] = { .type = NLA_U8 },
- [NL80211_ATTR_IE] = { .type = NLA_BINARY,
- .len = IEEE80211_MAX_DATA_LEN },
+ [NL80211_ATTR_IE] = NLA_POLICY_VALIDATE_FN(NLA_BINARY,
+ validate_ie_attr,
+ IEEE80211_MAX_DATA_LEN),
[NL80211_ATTR_SCAN_FREQUENCIES] = { .type = NLA_NESTED },
[NL80211_ATTR_SCAN_SSIDS] = { .type = NLA_NESTED },
@@ -341,10 +373,12 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
NLA_POLICY_RANGE(NLA_U32,
NL80211_HIDDEN_SSID_NOT_IN_USE,
NL80211_HIDDEN_SSID_ZERO_CONTENTS),
- [NL80211_ATTR_IE_PROBE_RESP] = { .type = NLA_BINARY,
- .len = IEEE80211_MAX_DATA_LEN },
- [NL80211_ATTR_IE_ASSOC_RESP] = { .type = NLA_BINARY,
- .len = IEEE80211_MAX_DATA_LEN },
+ [NL80211_ATTR_IE_PROBE_RESP] =
+ NLA_POLICY_VALIDATE_FN(NLA_BINARY, validate_ie_attr,
+ IEEE80211_MAX_DATA_LEN),
+ [NL80211_ATTR_IE_ASSOC_RESP] =
+ NLA_POLICY_VALIDATE_FN(NLA_BINARY, validate_ie_attr,
+ IEEE80211_MAX_DATA_LEN),
[NL80211_ATTR_ROAM_SUPPORT] = { .type = NLA_FLAG },
[NL80211_ATTR_SCHED_SCAN_MATCH] = { .type = NLA_NESTED },
[NL80211_ATTR_TX_NO_CCK_RATE] = { .type = NLA_FLAG },
@@ -649,36 +683,6 @@ static int nl80211_prepare_wdev_dump(struct netlink_callback *cb,
return 0;
}
-/* IE validation */
-static bool is_valid_ie_attr(const struct nlattr *attr)
-{
- const u8 *pos;
- int len;
-
- if (!attr)
- return true;
-
- pos = nla_data(attr);
- len = nla_len(attr);
-
- while (len) {
- u8 elemlen;
-
- if (len < 2)
- return false;
- len -= 2;
-
- elemlen = pos[1];
- if (elemlen > len)
- return false;
-
- len -= elemlen;
- pos += 2 + elemlen;
- }
-
- return true;
-}
-
/* message building helper */
static inline void *nl80211hdr_put(struct sk_buff *skb, u32 portid, u32 seq,
int flags, u8 cmd)
@@ -4017,12 +4021,6 @@ static int nl80211_parse_beacon(struct cfg80211_registered_device *rdev,
bool haveinfo = false;
int err;
- if (!is_valid_ie_attr(attrs[NL80211_ATTR_BEACON_TAIL]) ||
- !is_valid_ie_attr(attrs[NL80211_ATTR_IE]) ||
- !is_valid_ie_attr(attrs[NL80211_ATTR_IE_PROBE_RESP]) ||
- !is_valid_ie_attr(attrs[NL80211_ATTR_IE_ASSOC_RESP]))
- return -EINVAL;
-
memset(bcn, 0, sizeof(*bcn));
if (attrs[NL80211_ATTR_BEACON_HEAD]) {
@@ -6188,8 +6186,9 @@ static const struct nla_policy
[NL80211_MESH_SETUP_USERSPACE_AUTH] = { .type = NLA_FLAG },
[NL80211_MESH_SETUP_AUTH_PROTOCOL] = { .type = NLA_U8 },
[NL80211_MESH_SETUP_USERSPACE_MPM] = { .type = NLA_FLAG },
- [NL80211_MESH_SETUP_IE] = { .type = NLA_BINARY,
- .len = IEEE80211_MAX_DATA_LEN },
+ [NL80211_MESH_SETUP_IE] =
+ NLA_POLICY_VALIDATE_FN(NLA_BINARY, validate_ie_attr,
+ IEEE80211_MAX_DATA_LEN),
[NL80211_MESH_SETUP_USERSPACE_AMPE] = { .type = NLA_FLAG },
};
@@ -6369,8 +6368,6 @@ static int nl80211_parse_mesh_setup(struct genl_info *info,
if (tb[NL80211_MESH_SETUP_IE]) {
struct nlattr *ieattr =
tb[NL80211_MESH_SETUP_IE];
- if (!is_valid_ie_attr(ieattr))
- return -EINVAL;
setup->ie = nla_data(ieattr);
setup->ie_len = nla_len(ieattr);
}
@@ -7003,9 +7000,6 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info)
int err, tmp, n_ssids = 0, n_channels, i;
size_t ie_len;
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
-
wiphy = &rdev->wiphy;
if (wdev->iftype == NL80211_IFTYPE_NAN)
@@ -7359,9 +7353,6 @@ nl80211_parse_sched_scan(struct wiphy *wiphy, struct wireless_dev *wdev,
struct nlattr *tb[NL80211_SCHED_SCAN_MATCH_ATTR_MAX + 1];
s32 default_match_rssi = NL80211_SCAN_RSSI_THOLD_OFF;
- if (!is_valid_ie_attr(attrs[NL80211_ATTR_IE]))
- return ERR_PTR(-EINVAL);
-
if (attrs[NL80211_ATTR_SCAN_FREQUENCIES]) {
n_channels = validate_scan_freqs(
attrs[NL80211_ATTR_SCAN_FREQUENCIES]);
@@ -8329,9 +8320,6 @@ static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
struct key_parse key;
bool local_state_change;
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
-
if (!info->attrs[NL80211_ATTR_MAC])
return -EINVAL;
@@ -8570,9 +8558,6 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
dev->ieee80211_ptr->conn_owner_nlportid != info->snd_portid)
return -EPERM;
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
-
if (!info->attrs[NL80211_ATTR_MAC] ||
!info->attrs[NL80211_ATTR_SSID] ||
!info->attrs[NL80211_ATTR_WIPHY_FREQ])
@@ -8696,9 +8681,6 @@ static int nl80211_deauthenticate(struct sk_buff *skb, struct genl_info *info)
dev->ieee80211_ptr->conn_owner_nlportid != info->snd_portid)
return -EPERM;
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
-
if (!info->attrs[NL80211_ATTR_MAC])
return -EINVAL;
@@ -8747,9 +8729,6 @@ static int nl80211_disassociate(struct sk_buff *skb, struct genl_info *info)
dev->ieee80211_ptr->conn_owner_nlportid != info->snd_portid)
return -EPERM;
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
-
if (!info->attrs[NL80211_ATTR_MAC])
return -EINVAL;
@@ -8824,9 +8803,6 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
memset(&ibss, 0, sizeof(ibss));
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
-
if (!info->attrs[NL80211_ATTR_SSID] ||
!nla_len(info->attrs[NL80211_ATTR_SSID]))
return -EINVAL;
@@ -9264,9 +9240,6 @@ static int nl80211_connect(struct sk_buff *skb, struct genl_info *info)
memset(&connect, 0, sizeof(connect));
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
-
if (!info->attrs[NL80211_ATTR_SSID] ||
!nla_len(info->attrs[NL80211_ATTR_SSID]))
return -EINVAL;
@@ -9497,8 +9470,6 @@ static int nl80211_update_connect_params(struct sk_buff *skb,
return -EOPNOTSUPP;
if (info->attrs[NL80211_ATTR_IE]) {
- if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
- return -EINVAL;
connect.ie = nla_data(info->attrs[NL80211_ATTR_IE]);
connect.ie_len = nla_len(info->attrs[NL80211_ATTR_IE]);
changed |= UPDATE_ASSOC_IES;
@@ -12149,8 +12120,7 @@ static int nl80211_update_ft_ies(struct sk_buff *skb, struct genl_info *info)
return -EOPNOTSUPP;
if (!info->attrs[NL80211_ATTR_MDID] ||
- !info->attrs[NL80211_ATTR_IE] ||
- !is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
+ !info->attrs[NL80211_ATTR_IE])
return -EINVAL;
memset(&ft_params, 0, sizeof(ft_params));
--
2.14.4
