2021-06-20 05:40:05

by Sean Wang

[permalink] [raw]
Subject: [PATCH] mt76: mt7921: add .set_sar_specs support

From: YN Chen <[email protected]>

add .set_sar_specs to allow configuring SAR power limitations on the
frequency ranges from the userland.

Co-developed-by: Sean Wang <[email protected]>
Signed-off-by: Sean Wang <[email protected]>
Signed-off-by: YN Chen <[email protected]>
---
drivers/net/wireless/mediatek/mt76/mt76.h | 3 ++
.../net/wireless/mediatek/mt76/mt76_connac.h | 5 +++
.../wireless/mediatek/mt76/mt76_connac_mcu.c | 24 +++++++++-
.../net/wireless/mediatek/mt76/mt7921/init.c | 21 +++++++++
.../net/wireless/mediatek/mt76/mt7921/main.c | 45 +++++++++++++++++++
5 files changed, 97 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index 25c5ceef5257..63ce5242c4d5 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -636,6 +636,9 @@ struct mt76_phy {
struct sk_buff **tail;
u16 seqno;
} rx_amsdu[__MT_RXQ_MAX];
+
+ void *frp_data;
+ u8 num_frps;
};

struct mt76_dev {
diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac.h b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
index f49d97d0a1c5..95c7d1cac7c4 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76_connac.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
@@ -83,6 +83,11 @@ struct mt76_connac_coredump {
unsigned long last_activity;
};

+struct mt76_connac_freq_range_power {
+ const struct cfg80211_sar_freq_ranges *range;
+ s8 power;
+};
+
extern const struct wiphy_wowlan_support mt76_connac_wowlan_support;

static inline bool is_mt7921(struct mt76_dev *dev)
diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
index 5c3a81e5f559..07f45cb4f500 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
@@ -1749,6 +1749,24 @@ mt76_connac_mcu_build_sku(struct mt76_dev *dev, s8 *sku,
}
}

+static s8 mt76_connac_get_sar_power(struct mt76_phy *phy,
+ struct ieee80211_channel *chan,
+ s8 target_power)
+{
+ struct mt76_connac_freq_range_power *frp = phy->frp_data;
+ int freq, i;
+
+ freq = ieee80211_channel_to_frequency(chan->hw_value, chan->band);
+ for (i = 0 ; i < phy->num_frps; i++) {
+ if (frp[i].range &&
+ freq >= frp[i].range->start_freq &&
+ freq < frp[i].range->end_freq)
+ target_power = min_t(s8, frp[i].power, target_power);
+ }
+
+ return target_power;
+}
+
static int
mt76_connac_mcu_rate_txpower_band(struct mt76_phy *phy,
enum nl80211_band band)
@@ -1816,9 +1834,13 @@ mt76_connac_mcu_rate_txpower_band(struct mt76_phy *phy,
.hw_value = ch_list[idx],
.band = band,
};
+ s8 sar_power;
+
+ sar_power = mt76_connac_get_sar_power(phy, &chan,
+ tx_power);

mt76_get_rate_power_limits(phy, &chan, &limits,
- tx_power);
+ sar_power);

tx_power_tlv.last_msg = ch_list[idx] == last_ch;
sku_tlbv.channel = ch_list[idx];
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/init.c b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
index a9ce10b98827..e7f66d988a49 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
@@ -24,6 +24,20 @@ static const struct ieee80211_iface_combination if_comb[] = {
}
};

+const struct cfg80211_sar_freq_ranges mt7921_sar_freq_ranges[] = {
+ { .start_freq = 2402, .end_freq = 2494, },
+ { .start_freq = 5150, .end_freq = 5350, },
+ { .start_freq = 5350, .end_freq = 5470, },
+ { .start_freq = 5470, .end_freq = 5725, },
+ { .start_freq = 5725, .end_freq = 5950, },
+};
+
+static const struct cfg80211_sar_capa mt7921_sar_capa = {
+ .type = NL80211_SAR_TYPE_POWER,
+ .num_freq_ranges = ARRAY_SIZE(mt7921_sar_freq_ranges),
+ .freq_ranges = &mt7921_sar_freq_ranges[0],
+};
+
static void
mt7921_regd_notifier(struct wiphy *wiphy,
struct regulatory_request *request)
@@ -75,6 +89,13 @@ mt7921_init_wiphy(struct ieee80211_hw *hw)
wiphy->max_sched_scan_reqs = 1;
wiphy->flags |= WIPHY_FLAG_HAS_CHANNEL_SWITCH;
wiphy->reg_notifier = mt7921_regd_notifier;
+ wiphy->sar_capa = &mt7921_sar_capa;
+
+ phy->mt76->frp_data = devm_kcalloc(dev->mt76.dev,
+ wiphy->sar_capa->num_freq_ranges,
+ sizeof(struct mt76_connac_freq_range_power),
+ GFP_KERNEL);
+ phy->mt76->num_frps = wiphy->sar_capa->num_freq_ranges;

wiphy->features |= NL80211_FEATURE_SCHED_SCAN_RANDOM_MAC_ADDR |
NL80211_FEATURE_SCAN_RANDOM_MAC_ADDR;
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
index 7fd21049ff5a..e9b5d79e139f 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
@@ -1171,6 +1171,50 @@ static void mt7921_sta_set_decap_offload(struct ieee80211_hw *hw,
MCU_UNI_CMD_STA_REC_UPDATE);
}

+static int mt7921_set_sar_specs(struct ieee80211_hw *hw,
+ const struct cfg80211_sar_specs *sar)
+{
+ const struct cfg80211_sar_capa *capa = hw->wiphy->sar_capa;
+ struct mt76_connac_freq_range_power *frp_data, *frp;
+ struct mt7921_dev *dev = mt7921_hw_dev(hw);
+ struct mt76_phy *mphy = hw->priv;
+ int err;
+ u32 i;
+
+ mt7921_mutex_acquire(dev);
+
+ if (!sar || sar->type != NL80211_SAR_TYPE_POWER ||
+ sar->num_sub_specs == 0) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ frp_data = mphy->frp_data;
+
+ for (i = 0; i < sar->num_sub_specs; i++) {
+ u32 index = sar->sub_specs[i].freq_range_index;
+ /* SAR specifies power limitaton in 0.25dbm */
+ s32 power = sar->sub_specs[i].power >> 1;
+
+ if (power > 127 || power < -127)
+ power = 127;
+
+ if (index >= mphy->num_frps)
+ continue;
+
+ frp = &frp_data[index];
+ frp->range = &capa->freq_ranges[index];
+ frp->power = power;
+ }
+
+ err = mt76_connac_mcu_set_rate_txpower(mphy);
+
+out:
+ mt7921_mutex_release(dev);
+
+ return err;
+}
+
const struct ieee80211_ops mt7921_ops = {
.tx = mt7921_tx,
.start = mt7921_start,
@@ -1209,4 +1253,5 @@ const struct ieee80211_ops mt7921_ops = {
.set_rekey_data = mt7921_set_rekey_data,
#endif /* CONFIG_PM */
.flush = mt7921_flush,
+ .set_sar_specs = mt7921_set_sar_specs,
};
--
2.25.1


2021-06-20 09:49:21

by Lorenzo Bianconi

[permalink] [raw]
Subject: Re: [PATCH] mt76: mt7921: add .set_sar_specs support

> From: YN Chen <[email protected]>
>
> add .set_sar_specs to allow configuring SAR power limitations on the
> frequency ranges from the userland.
>
> Co-developed-by: Sean Wang <[email protected]>
> Signed-off-by: Sean Wang <[email protected]>
> Signed-off-by: YN Chen <[email protected]>
> ---
> drivers/net/wireless/mediatek/mt76/mt76.h | 3 ++
> .../net/wireless/mediatek/mt76/mt76_connac.h | 5 +++
> .../wireless/mediatek/mt76/mt76_connac_mcu.c | 24 +++++++++-
> .../net/wireless/mediatek/mt76/mt7921/init.c | 21 +++++++++
> .../net/wireless/mediatek/mt76/mt7921/main.c | 45 +++++++++++++++++++
> 5 files changed, 97 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
> index 25c5ceef5257..63ce5242c4d5 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt76.h
> +++ b/drivers/net/wireless/mediatek/mt76/mt76.h
> @@ -636,6 +636,9 @@ struct mt76_phy {
> struct sk_buff **tail;
> u16 seqno;
> } rx_amsdu[__MT_RXQ_MAX];
> +
> + void *frp_data;
> + u8 num_frps;
> };
>
> struct mt76_dev {
> diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac.h b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
> index f49d97d0a1c5..95c7d1cac7c4 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt76_connac.h
> +++ b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
> @@ -83,6 +83,11 @@ struct mt76_connac_coredump {
> unsigned long last_activity;
> };
>
> +struct mt76_connac_freq_range_power {
> + const struct cfg80211_sar_freq_ranges *range;
> + s8 power;
> +};
> +
> extern const struct wiphy_wowlan_support mt76_connac_wowlan_support;
>
> static inline bool is_mt7921(struct mt76_dev *dev)
> diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
> index 5c3a81e5f559..07f45cb4f500 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
> @@ -1749,6 +1749,24 @@ mt76_connac_mcu_build_sku(struct mt76_dev *dev, s8 *sku,
> }
> }
>
> +static s8 mt76_connac_get_sar_power(struct mt76_phy *phy,
> + struct ieee80211_channel *chan,
> + s8 target_power)
> +{
> + struct mt76_connac_freq_range_power *frp = phy->frp_data;
> + int freq, i;
> +
> + freq = ieee80211_channel_to_frequency(chan->hw_value, chan->band);
> + for (i = 0 ; i < phy->num_frps; i++) {
> + if (frp[i].range &&
> + freq >= frp[i].range->start_freq &&
> + freq < frp[i].range->end_freq)
> + target_power = min_t(s8, frp[i].power, target_power);

can we have overlapping freq range? if not I guess you can add a break here.

> + }
> +
> + return target_power;
> +}
> +
> static int
> mt76_connac_mcu_rate_txpower_band(struct mt76_phy *phy,
> enum nl80211_band band)
> @@ -1816,9 +1834,13 @@ mt76_connac_mcu_rate_txpower_band(struct mt76_phy *phy,
> .hw_value = ch_list[idx],
> .band = band,
> };
> + s8 sar_power;
> +
> + sar_power = mt76_connac_get_sar_power(phy, &chan,
> + tx_power);
>
> mt76_get_rate_power_limits(phy, &chan, &limits,
> - tx_power);
> + sar_power);
>
> tx_power_tlv.last_msg = ch_list[idx] == last_ch;
> sku_tlbv.channel = ch_list[idx];
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/init.c b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
> index a9ce10b98827..e7f66d988a49 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7921/init.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
> @@ -24,6 +24,20 @@ static const struct ieee80211_iface_combination if_comb[] = {
> }
> };
>
> +const struct cfg80211_sar_freq_ranges mt7921_sar_freq_ranges[] = {
> + { .start_freq = 2402, .end_freq = 2494, },
> + { .start_freq = 5150, .end_freq = 5350, },
> + { .start_freq = 5350, .end_freq = 5470, },
> + { .start_freq = 5470, .end_freq = 5725, },
> + { .start_freq = 5725, .end_freq = 5950, },
> +};
> +
> +static const struct cfg80211_sar_capa mt7921_sar_capa = {
> + .type = NL80211_SAR_TYPE_POWER,
> + .num_freq_ranges = ARRAY_SIZE(mt7921_sar_freq_ranges),
> + .freq_ranges = &mt7921_sar_freq_ranges[0],
> +};
> +
> static void
> mt7921_regd_notifier(struct wiphy *wiphy,
> struct regulatory_request *request)
> @@ -75,6 +89,13 @@ mt7921_init_wiphy(struct ieee80211_hw *hw)
> wiphy->max_sched_scan_reqs = 1;
> wiphy->flags |= WIPHY_FLAG_HAS_CHANNEL_SWITCH;
> wiphy->reg_notifier = mt7921_regd_notifier;
> + wiphy->sar_capa = &mt7921_sar_capa;
> +
> + phy->mt76->frp_data = devm_kcalloc(dev->mt76.dev,
> + wiphy->sar_capa->num_freq_ranges,
> + sizeof(struct mt76_connac_freq_range_power),
> + GFP_KERNEL);

Here I guess we need to check if devm_kcalloc fails returning an int from
mt7921_init_wiphy()

> + phy->mt76->num_frps = wiphy->sar_capa->num_freq_ranges;
>
> wiphy->features |= NL80211_FEATURE_SCHED_SCAN_RANDOM_MAC_ADDR |
> NL80211_FEATURE_SCAN_RANDOM_MAC_ADDR;
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
> index 7fd21049ff5a..e9b5d79e139f 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
> @@ -1171,6 +1171,50 @@ static void mt7921_sta_set_decap_offload(struct ieee80211_hw *hw,
> MCU_UNI_CMD_STA_REC_UPDATE);
> }
>
> +static int mt7921_set_sar_specs(struct ieee80211_hw *hw,
> + const struct cfg80211_sar_specs *sar)
> +{
> + const struct cfg80211_sar_capa *capa = hw->wiphy->sar_capa;
> + struct mt76_connac_freq_range_power *frp_data, *frp;
> + struct mt7921_dev *dev = mt7921_hw_dev(hw);
> + struct mt76_phy *mphy = hw->priv;
> + int err;
> + u32 i;
> +
> + mt7921_mutex_acquire(dev);
> +
> + if (!sar || sar->type != NL80211_SAR_TYPE_POWER ||
> + sar->num_sub_specs == 0) {
> + err = -EINVAL;
> + goto out;
> + }

I guess you can move this out of the lock

> +
> + frp_data = mphy->frp_data;
> +
> + for (i = 0; i < sar->num_sub_specs; i++) {
> + u32 index = sar->sub_specs[i].freq_range_index;
> + /* SAR specifies power limitaton in 0.25dbm */
> + s32 power = sar->sub_specs[i].power >> 1;
> +
> + if (power > 127 || power < -127)
> + power = 127;
> +
> + if (index >= mphy->num_frps)
> + continue;
> +
> + frp = &frp_data[index];
> + frp->range = &capa->freq_ranges[index];

I guess there is an use-after-free here since sar is freed at the end of
nl80211_set_sar_specs, right?

Regards,
Lorenzo

> + frp->power = power;
> + }
> +
> + err = mt76_connac_mcu_set_rate_txpower(mphy);
> +
> +out:
> + mt7921_mutex_release(dev);
> +
> + return err;
> +}
> +
> const struct ieee80211_ops mt7921_ops = {
> .tx = mt7921_tx,
> .start = mt7921_start,
> @@ -1209,4 +1253,5 @@ const struct ieee80211_ops mt7921_ops = {
> .set_rekey_data = mt7921_set_rekey_data,
> #endif /* CONFIG_PM */
> .flush = mt7921_flush,
> + .set_sar_specs = mt7921_set_sar_specs,
> };
> --
> 2.25.1
>


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2021-06-21 22:47:58

by Sean Wang

[permalink] [raw]
Subject: Re: [PATCH] mt76: mt7921: add .set_sar_specs support

From: Sean Wang <[email protected]>

>> From: YN Chen <[email protected]>
>>
>> add .set_sar_specs to allow configuring SAR power limitations on the
>> frequency ranges from the userland.
>>
>> Co-developed-by: Sean Wang <[email protected]>
>> Signed-off-by: Sean Wang <[email protected]>
>> Signed-off-by: YN Chen <[email protected]>
>> ---
>> drivers/net/wireless/mediatek/mt76/mt76.h | 3 ++
>> .../net/wireless/mediatek/mt76/mt76_connac.h | 5 +++
>> .../wireless/mediatek/mt76/mt76_connac_mcu.c | 24 +++++++++-
>> .../net/wireless/mediatek/mt76/mt7921/init.c | 21 +++++++++
>> .../net/wireless/mediatek/mt76/mt7921/main.c | 45 +++++++++++++++++++
>> 5 files changed, 97 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h
>> b/drivers/net/wireless/mediatek/mt76/mt76.h
>> index 25c5ceef5257..63ce5242c4d5 100644
>> --- a/drivers/net/wireless/mediatek/mt76/mt76.h
>> +++ b/drivers/net/wireless/mediatek/mt76/mt76.h
>> @@ -636,6 +636,9 @@ struct mt76_phy {
>> struct sk_buff **tail;
>> u16 seqno;
>> } rx_amsdu[__MT_RXQ_MAX];
>> +
>> + void *frp_data;
>> + u8 num_frps;
>> };
>>
>> struct mt76_dev {
>> diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac.h
>> b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
>> index f49d97d0a1c5..95c7d1cac7c4 100644
>> --- a/drivers/net/wireless/mediatek/mt76/mt76_connac.h
>> +++ b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
>> @@ -83,6 +83,11 @@ struct mt76_connac_coredump {
>> unsigned long last_activity;
>> };
>>
>> +struct mt76_connac_freq_range_power {
>> + const struct cfg80211_sar_freq_ranges *range;
>> + s8 power;
>> +};
>> +
>> extern const struct wiphy_wowlan_support mt76_connac_wowlan_support;
>>
>> static inline bool is_mt7921(struct mt76_dev *dev) diff --git
>> a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
>> b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
>> index 5c3a81e5f559..07f45cb4f500 100644
>> --- a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
>> +++ b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
>> @@ -1749,6 +1749,24 @@ mt76_connac_mcu_build_sku(struct mt76_dev *dev, s8 *sku,
>> }
>> }
>>
>> +static s8 mt76_connac_get_sar_power(struct mt76_phy *phy,
>> + struct ieee80211_channel *chan,
>> + s8 target_power)
>> +{
>> + struct mt76_connac_freq_range_power *frp = phy->frp_data;
>> + int freq, i;
>> +
>> + freq = ieee80211_channel_to_frequency(chan->hw_value, chan->band);
>> + for (i = 0 ; i < phy->num_frps; i++) {
>> + if (frp[i].range &&
>> + freq >= frp[i].range->start_freq &&
>> + freq < frp[i].range->end_freq)
>> + target_power = min_t(s8, frp[i].power, target_power);
>
>can we have overlapping freq range? if not I guess you can add a break here.

It is supposed to be there is no overlapping freq range for the real use case. I will add a break in the next version.
>
>
>> + }
>> +
>> + return target_power;
>> +}
>> +
>> static int
>> mt76_connac_mcu_rate_txpower_band(struct mt76_phy *phy,
>> enum nl80211_band band)
>> @@ -1816,9 +1834,13 @@ mt76_connac_mcu_rate_txpower_band(struct mt76_phy *phy,
>> .hw_value = ch_list[idx],
>> .band = band,
>> };
>> + s8 sar_power;
>> +
>> + sar_power = mt76_connac_get_sar_power(phy, &chan,
>> + tx_power);
>>
>> mt76_get_rate_power_limits(phy, &chan, &limits,
>> - tx_power);
>> + sar_power);
>>
>> tx_power_tlv.last_msg = ch_list[idx] == last_ch;
>> sku_tlbv.channel = ch_list[idx];
>> diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/init.c
>> b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
>> index a9ce10b98827..e7f66d988a49 100644
>> --- a/drivers/net/wireless/mediatek/mt76/mt7921/init.c
>> +++ b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
>> @@ -24,6 +24,20 @@ static const struct ieee80211_iface_combination if_comb[] = {
>> }
>> };
>>
>> +const struct cfg80211_sar_freq_ranges mt7921_sar_freq_ranges[] = {
>> + { .start_freq = 2402, .end_freq = 2494, },
>> + { .start_freq = 5150, .end_freq = 5350, },
>> + { .start_freq = 5350, .end_freq = 5470, },
>> + { .start_freq = 5470, .end_freq = 5725, },
>> + { .start_freq = 5725, .end_freq = 5950, }, };
>> +
>> +static const struct cfg80211_sar_capa mt7921_sar_capa = {
>> + .type = NL80211_SAR_TYPE_POWER,
>> + .num_freq_ranges = ARRAY_SIZE(mt7921_sar_freq_ranges),
>> + .freq_ranges = &mt7921_sar_freq_ranges[0], };
>> +
>> static void
>> mt7921_regd_notifier(struct wiphy *wiphy,
>> struct regulatory_request *request) @@ -75,6 +89,13 @@
>> mt7921_init_wiphy(struct ieee80211_hw *hw)
>> wiphy->max_sched_scan_reqs = 1;
>> wiphy->flags |= WIPHY_FLAG_HAS_CHANNEL_SWITCH;
>> wiphy->reg_notifier = mt7921_regd_notifier;
>> + wiphy->sar_capa = &mt7921_sar_capa;
>> +
>> + phy->mt76->frp_data = devm_kcalloc(dev->mt76.dev,
>> + wiphy->sar_capa->num_freq_ranges,
>> + sizeof(struct mt76_connac_freq_range_power),
>> + GFP_KERNEL);
>
>Here I guess we need to check if devm_kcalloc fails returning an int from
>mt7921_init_wiphy()

Sure, will do it.

>
>> + phy->mt76->num_frps = wiphy->sar_capa->num_freq_ranges;
>>
>> wiphy->features |= NL80211_FEATURE_SCHED_SCAN_RANDOM_MAC_ADDR |
>> NL80211_FEATURE_SCAN_RANDOM_MAC_ADDR;
>> diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
>> b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
>> index 7fd21049ff5a..e9b5d79e139f 100644
>> --- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
>> +++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
>> @@ -1171,6 +1171,50 @@ static void mt7921_sta_set_decap_offload(struct ieee80211_hw *hw,
>> MCU_UNI_CMD_STA_REC_UPDATE); }
>>
>> +static int mt7921_set_sar_specs(struct ieee80211_hw *hw,
>> + const struct cfg80211_sar_specs *sar) {
>> + const struct cfg80211_sar_capa *capa = hw->wiphy->sar_capa;
>> + struct mt76_connac_freq_range_power *frp_data, *frp;
>> + struct mt7921_dev *dev = mt7921_hw_dev(hw);
>> + struct mt76_phy *mphy = hw->priv;
>> + int err;
>> + u32 i;
>> +
>> + mt7921_mutex_acquire(dev);
>> +
>> + if (!sar || sar->type != NL80211_SAR_TYPE_POWER ||
>> + sar->num_sub_specs == 0) {
>> + err = -EINVAL;
>> + goto out;
>> + }
>
>I guess you can move this out of the lock
>

Sure, will do it.

>> +
>> + frp_data = mphy->frp_data;
>> +
>> + for (i = 0; i < sar->num_sub_specs; i++) {
>> + u32 index = sar->sub_specs[i].freq_range_index;
>> + /* SAR specifies power limitaton in 0.25dbm */
>> + s32 power = sar->sub_specs[i].power >> 1;
>> +
>> + if (power > 127 || power < -127)
>> + power = 127;
>> +
>> + if (index >= mphy->num_frps)
>> + continue;
>> +
>> + frp = &frp_data[index];
>> + frp->range = &capa->freq_ranges[index];
>
>I guess there is an use-after-free here since sar is freed at the end of nl80211_set_sar_specs, right?
>

Nope, there is no use-after-free case happens here because frp->range just points to an entry of const struct cfg80211_sar_specs table, not the one created from nl80211_set_sar_specs.

>Regards,
>Lorenzo
>
>> + frp->power = power;
>> + }
>> +
>> + err = mt76_connac_mcu_set_rate_txpower(mphy);
>> +
>> +out:
>> + mt7921_mutex_release(dev);
>> +
>> + return err;
>> +}
>> +
>> const struct ieee80211_ops mt7921_ops = {
>> .tx = mt7921_tx,
>> .start = mt7921_start,
>> @@ -1209,4 +1253,5 @@ const struct ieee80211_ops mt7921_ops = {
>> .set_rekey_data = mt7921_set_rekey_data, #endif /* CONFIG_PM */
>> .flush = mt7921_flush,
>> + .set_sar_specs = mt7921_set_sar_specs,
>> };
>> --
>> 2.25.1
>>

2021-06-22 06:44:00

by Lorenzo Bianconi

[permalink] [raw]
Subject: Re: [PATCH] mt76: mt7921: add .set_sar_specs support

[...]
> >
> >I guess there is an use-after-free here since sar is freed at the end of nl80211_set_sar_specs, right?
> >
>
> Nope, there is no use-after-free case happens here because frp->range just points to an entry of const struct cfg80211_sar_specs table, not the one created from nl80211_set_sar_specs.

ack, right. I misread the code.

Regards,
Lorenzo

>
> >Regards,
> >Lorenzo
> >
> >> + frp->power = power;
> >> + }
> >> +
> >> + err = mt76_connac_mcu_set_rate_txpower(mphy);
> >> +
> >> +out:
> >> + mt7921_mutex_release(dev);
> >> +
> >> + return err;
> >> +}
> >> +
> >> const struct ieee80211_ops mt7921_ops = {
> >> .tx = mt7921_tx,
> >> .start = mt7921_start,
> >> @@ -1209,4 +1253,5 @@ const struct ieee80211_ops mt7921_ops = {
> >> .set_rekey_data = mt7921_set_rekey_data, #endif /* CONFIG_PM */
> >> .flush = mt7921_flush,
> >> + .set_sar_specs = mt7921_set_sar_specs,
> >> };
> >> --
> >> 2.25.1
> >>


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