2022-05-17 07:49:05

by Baochen Qiang

Subject: [PATCH] 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 <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Baochen Qiang <[email protected]>
---
drivers/net/wireless/ath/ath11k/mac.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index ee1590b16eff..7d574ad67e59 100644
--- 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",

base-commit: 14c24bc11b43da59fe41d79d3c1b29decc3d21f3
--
2.25.1

2022-05-23 07:18:16

by Kalle Valo

Subject: Re: [PATCH] ath11k: Fix warning on variable 'sar' dereference before check

Baochen Qiang <[email protected]> wrote:

> 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 <[email protected]>
> Reported-by: Dan Carpenter <[email protected]>
> Signed-off-by: Baochen Qiang <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>

Patch applied to ath-next branch of ath.git, thanks.

77bbbd5e0ed3 ath11k: Fix warning on variable 'sar' dereference before check

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches