2024-06-14 17:33:11

by Dan Carpenter

Subject: [PATCH] wifi: ath12k: fix potential NULL dereference

In this condition if "sband" is NULL then it leads to a NULL dereference
on the next line when it does "idx -= sband->n_channels;".

The condition can just be deleted, because if "sband" is NULL or the
"idx" is out of bounds, then the correct thing is to at this point is to
return -ENOENT. There are no additional sbands available to try.

Fixes: 70e3be54bbdd ("wifi: ath12k: fix survey dump collection in 6 GHz")
Signed-off-by: Dan Carpenter <[email protected]>
---
drivers/net/wireless/ath/ath12k/mac.c | 5 -----
1 file changed, 5 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index 509c02bffdae..e5456383dabd 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -8314,11 +8314,6 @@ static int ath12k_mac_op_get_survey(struct ieee80211_hw *hw, int idx,

if (!sband)
sband = hw->wiphy->bands[NL80211_BAND_6GHZ];
- if (!sband || idx >= sband->n_channels) {
- idx -= sband->n_channels;
- sband = NULL;
- }
-
if (!sband || idx >= sband->n_channels)
return -ENOENT;

--
2.43.0

2024-06-15 22:41:56

by Jeff Johnson

Subject: Re: [PATCH] wifi: ath12k: fix potential NULL dereference

On 6/14/2024 10:32 AM, Dan Carpenter wrote:
> In this condition if "sband" is NULL then it leads to a NULL dereference
> on the next line when it does "idx -= sband->n_channels;".
>
> The condition can just be deleted, because if "sband" is NULL or the
> "idx" is out of bounds, then the correct thing is to at this point is to
> return -ENOENT. There are no additional sbands available to try.
>
> Fixes: 70e3be54bbdd ("wifi: ath12k: fix survey dump collection in 6 GHz")
> Signed-off-by: Dan Carpenter <[email protected]>
> ---
> drivers/net/wireless/ath/ath12k/mac.c | 5 -----
> 1 file changed, 5 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
> index 509c02bffdae..e5456383dabd 100644
> --- a/drivers/net/wireless/ath/ath12k/mac.c
> +++ b/drivers/net/wireless/ath/ath12k/mac.c
> @@ -8314,11 +8314,6 @@ static int ath12k_mac_op_get_survey(struct ieee80211_hw *hw, int idx,
>
> if (!sband)
> sband = hw->wiphy->bands[NL80211_BAND_6GHZ];
> - if (!sband || idx >= sband->n_channels) {
> - idx -= sband->n_channels;
> - sband = NULL;
> - }
> -
> if (!sband || idx >= sband->n_channels)
> return -ENOENT;
>
This duplicates
https://lore.kernel.org/all/[email protected]/