In function ieee80211_prep_channel(), it has some ieee80211_bss_get_ie()
and cfg80211_find_ext_ie() to get the IE, this is to use another
function ieee802_11_parse_elems() to get all the IEs in one time.
Signed-off-by: Wen Gong <[email protected]>
---
net/mac80211/mlme.c | 52 +++++++++++++++++++++++++++++++--------------
1 file changed, 36 insertions(+), 16 deletions(-)
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index e80f3388b0c5..6e8e90ee8b6c 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -4998,10 +4998,22 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
bool is_6ghz = cbss->channel->band == NL80211_BAND_6GHZ;
bool is_5ghz = cbss->channel->band == NL80211_BAND_5GHZ;
struct ieee80211_bss *bss = (void *)cbss->priv;
+ struct ieee802_11_elems *elems;
+ const struct cfg80211_bss_ies *ies;
int ret;
u32 i;
bool have_80mhz;
+ rcu_read_lock();
+
+ ies = rcu_dereference(cbss->ies);
+ elems = ieee802_11_parse_elems(ies->data, ies->len, false,
+ NULL, NULL);
+ if (!elems) {
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+
sband = local->hw.wiphy->bands[cbss->channel->band];
ifmgd->flags &= ~(IEEE80211_STA_DISABLE_40MHZ |
@@ -5024,16 +5036,18 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
ieee80211_vif_type_p2p(&sdata->vif)))
ifmgd->flags |= IEEE80211_STA_DISABLE_HE;
- rcu_read_lock();
-
if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT) && !is_6ghz) {
const u8 *ht_oper_ie, *ht_cap_ie;
- ht_oper_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_OPERATION);
+ ht_oper_ie = elems->ht_operation ?
+ ((const u8 *)elems->ht_operation) - 2 :
+ NULL;
if (ht_oper_ie && ht_oper_ie[1] >= sizeof(*ht_oper))
ht_oper = (void *)(ht_oper_ie + 2);
- ht_cap_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_CAPABILITY);
+ ht_cap_ie = elems->ht_cap_elem ?
+ ((const u8 *)elems->ht_cap_elem) - 2 :
+ NULL;
if (ht_cap_ie && ht_cap_ie[1] >= sizeof(*ht_cap))
ht_cap = (void *)(ht_cap_ie + 2);
@@ -5046,8 +5060,9 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
if (!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT) && !is_6ghz) {
const u8 *vht_oper_ie, *vht_cap;
- vht_oper_ie = ieee80211_bss_get_ie(cbss,
- WLAN_EID_VHT_OPERATION);
+ vht_oper_ie = elems->vht_operation ?
+ ((const u8 *)elems->vht_operation) - 2 :
+ NULL;
if (vht_oper_ie && vht_oper_ie[1] >= sizeof(*vht_oper))
vht_oper = (void *)(vht_oper_ie + 2);
if (vht_oper && !ht_oper) {
@@ -5059,7 +5074,9 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
ifmgd->flags |= IEEE80211_STA_DISABLE_HE;
}
- vht_cap = ieee80211_bss_get_ie(cbss, WLAN_EID_VHT_CAPABILITY);
+ vht_cap = elems->vht_cap_elem ?
+ ((const u8 *)elems->vht_cap_elem) - 2 :
+ NULL;
if (!vht_cap || vht_cap[1] < sizeof(struct ieee80211_vht_cap)) {
ifmgd->flags |= IEEE80211_STA_DISABLE_VHT;
vht_oper = NULL;
@@ -5067,12 +5084,11 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
}
if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HE)) {
- const struct cfg80211_bss_ies *ies;
const u8 *he_oper_ie;
- ies = rcu_dereference(cbss->ies);
- he_oper_ie = cfg80211_find_ext_ie(WLAN_EID_EXT_HE_OPERATION,
- ies->data, ies->len);
+ he_oper_ie = elems->he_operation ?
+ ((const u8 *)elems->he_operation) - 3 :
+ NULL;
if (he_oper_ie &&
he_oper_ie[1] >= ieee80211_he_oper_size(&he_oper_ie[3]))
he_oper = (void *)(he_oper_ie + 3);
@@ -5100,8 +5116,9 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
if (sband->band == NL80211_BAND_S1GHZ) {
const u8 *s1g_oper_ie;
- s1g_oper_ie = ieee80211_bss_get_ie(cbss,
- WLAN_EID_S1G_OPERATION);
+ s1g_oper_ie = elems->s1g_oper ?
+ ((const u8 *)elems->s1g_oper) - 2 :
+ NULL;
if (s1g_oper_ie && s1g_oper_ie[1] >= sizeof(*s1g_oper))
s1g_oper = (void *)(s1g_oper_ie + 2);
else
@@ -5123,7 +5140,8 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
if (ifmgd->flags & IEEE80211_STA_DISABLE_HE && is_6ghz) {
sdata_info(sdata, "Rejecting non-HE 6/7 GHz connection");
- return -EINVAL;
+ ret = -EINVAL;
+ goto out_no_lock;
}
/* will change later if needed */
@@ -5141,15 +5159,17 @@ static int ieee80211_prep_channel(struct ieee80211_sub_if_data *sdata,
/* don't downgrade for 5 and 10 MHz channels, though. */
if (chandef.width == NL80211_CHAN_WIDTH_5 ||
chandef.width == NL80211_CHAN_WIDTH_10)
- goto out;
+ goto out_lock;
while (ret && chandef.width != NL80211_CHAN_WIDTH_20_NOHT) {
ifmgd->flags |= ieee80211_chandef_downgrade(&chandef);
ret = ieee80211_vif_use_channel(sdata, &chandef,
IEEE80211_CHANCTX_SHARED);
}
- out:
+ out_lock:
mutex_unlock(&local->mtx);
+ out_no_lock:
+ kfree(elems);
return ret;
}
--
2.31.1
Taking a brief look before lunch,
> if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT) && !is_6ghz) {
> const u8 *ht_oper_ie, *ht_cap_ie;
>
>
>
>
> - ht_oper_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_OPERATION);
> + ht_oper_ie = elems->ht_operation ?
> + ((const u8 *)elems->ht_operation) - 2 :
> + NULL;
> if (ht_oper_ie && ht_oper_ie[1] >= sizeof(*ht_oper))
> ht_oper = (void *)(ht_oper_ie + 2);
Can't we drop these checks, and simply do
ht_oper = elems->ht_operation?
After all, ieee802_11_parse_elems() should already be doing the
necessary length checks? We just didn't have that with
ieee80211_bss_get_ie().
> - ht_cap_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_CAPABILITY);
> + ht_cap_ie = elems->ht_cap_elem ?
> + ((const u8 *)elems->ht_cap_elem) - 2 :
> + NULL;
> if (ht_cap_ie && ht_cap_ie[1] >= sizeof(*ht_cap))
> ht_cap = (void *)(ht_cap_ie + 2);
Likewise for all the others.
johannes
On Fri, 2021-09-24 at 12:13 +0200, Johannes Berg wrote:
> Taking a brief look before lunch,
>
> > if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT) && !is_6ghz) {
> > const u8 *ht_oper_ie, *ht_cap_ie;
> >
> >
> >
> >
> > - ht_oper_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_OPERATION);
> > + ht_oper_ie = elems->ht_operation ?
> > + ((const u8 *)elems->ht_operation) - 2 :
> > + NULL;
> > if (ht_oper_ie && ht_oper_ie[1] >= sizeof(*ht_oper))
> > ht_oper = (void *)(ht_oper_ie + 2);
>
> Can't we drop these checks, and simply do
>
> ht_oper = elems->ht_operation?
I checked, yes, we can do that. Since I just did it anyway, no need to
resend.
johannes