ath11k: Fix warning on variable 'sar' dereference before check

We are seeing below warning:
warn: variable dereferenced before check 'sar'

Fix it by moving ahead pointer check on 'sar'.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3

Fixes: 652f69ed9c1b ("ath11k: Add support for SAR")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220517004844.2412660-1-quic_bqiang@quicinc.com

diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index ee1590b16eff7338e90adf995fd29fd78e57ca37..7d574ad67e5953d35eca02f3d9a58602b36be815 100644 (file)
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -8297,11 +8297,15 @@ static int ath11k_mac_op_set_bios_sar_specs(struct ieee80211_hw *hw,
                                            const struct cfg80211_sar_specs *sar)
 {
        struct ath11k *ar = hw->priv;
-       const struct cfg80211_sar_sub_specs *sspec = sar->sub_specs;
+       const struct cfg80211_sar_sub_specs *sspec;
        int ret, index;
        u8 *sar_tbl;
        u32 i;
 
+       if (!sar || sar->type != NL80211_SAR_TYPE_POWER ||
+           sar->num_sub_specs == 0)
+               return -EINVAL;
+
        mutex_lock(&ar->conf_mutex);
 
        if (!test_bit(WMI_TLV_SERVICE_BIOS_SAR_SUPPORT, ar->ab->wmi_ab.svc_map) ||
@@ -8310,12 +8314,6 @@ static int ath11k_mac_op_set_bios_sar_specs(struct ieee80211_hw *hw,
                goto exit;
        }
 
-       if (!sar || sar->type != NL80211_SAR_TYPE_POWER ||
-           sar->num_sub_specs == 0) {
-               ret = -EINVAL;
-               goto exit;
-       }
-
        ret = ath11k_wmi_pdev_set_bios_geo_table_param(ar);
        if (ret) {
                ath11k_warn(ar->ab, "failed to set geo table: %d\n", ret);
@@ -8328,6 +8326,7 @@ static int ath11k_mac_op_set_bios_sar_specs(struct ieee80211_hw *hw,
                goto exit;
        }
 
+       sspec = sar->sub_specs;
        for (i = 0; i < sar->num_sub_specs; i++) {
                if (sspec->freq_range_index >= (BIOS_SAR_TABLE_LEN >> 1)) {
                        ath11k_warn(ar->ab, "Ignore bad frequency index %u, max allowed %u\n",