2019-05-06 07:39:49

by Stanislaw Gruszka

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Subject: [PATCH 5.1] rtw88: fix subscript above array bounds compiler warning

My compiler complains about:

drivers/net/wireless/realtek/rtw88/phy.c: In function ‘rtw_phy_rf_power_2_rssi’:
drivers/net/wireless/realtek/rtw88/phy.c:430:26: warning: array subscript is above array bounds [-Warray-bounds]
linear = db_invert_table[i][j];

According to comment power_db should be in range 1 ~ 96 .
To fix add check for boundaries before access the array.

Signed-off-by: Stanislaw Gruszka <[email protected]>
---
RFC -> v1
- add check before accessing the array insted of
rtw_phy_power_2_db() change.
v1 -> v2:
- return 1 for power_db < 1

drivers/net/wireless/realtek/rtw88/phy.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtw88/phy.c b/drivers/net/wireless/realtek/rtw88/phy.c
index 4381b360b5b5..9ca52a4d025a 100644
--- a/drivers/net/wireless/realtek/rtw88/phy.c
+++ b/drivers/net/wireless/realtek/rtw88/phy.c
@@ -423,6 +423,11 @@ static u64 rtw_phy_db_2_linear(u8 power_db)
u8 i, j;
u64 linear;

+ if (power_db > 96)
+ power_db = 96;
+ else if (power_db < 1)
+ return 1;
+
/* 1dB ~ 96dB */
i = (power_db - 1) >> 3;
j = (power_db - 1) - (i << 3);
--
2.20.1


2019-05-06 08:29:44

by Tony Chuang

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Subject: RE: [PATCH 5.1] rtw88: fix subscript above array bounds compiler warning

> Subject: [PATCH 5.1] rtw88: fix subscript above array bounds compiler warning
>
> My compiler complains about:
>
> drivers/net/wireless/realtek/rtw88/phy.c: In function
> ‘rtw_phy_rf_power_2_rssi’:
> drivers/net/wireless/realtek/rtw88/phy.c:430:26: warning: array subscript is
> above array bounds [-Warray-bounds]
> linear = db_invert_table[i][j];
>
> According to comment power_db should be in range 1 ~ 96 .
> To fix add check for boundaries before access the array.
>
> Signed-off-by: Stanislaw Gruszka <[email protected]>
> ---
> RFC -> v1
> - add check before accessing the array insted of
> rtw_phy_power_2_db() change.
> v1 -> v2:
> - return 1 for power_db < 1
>
> drivers/net/wireless/realtek/rtw88/phy.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/net/wireless/realtek/rtw88/phy.c
> b/drivers/net/wireless/realtek/rtw88/phy.c
> index 4381b360b5b5..9ca52a4d025a 100644
> --- a/drivers/net/wireless/realtek/rtw88/phy.c
> +++ b/drivers/net/wireless/realtek/rtw88/phy.c
> @@ -423,6 +423,11 @@ static u64 rtw_phy_db_2_linear(u8 power_db)
> u8 i, j;
> u64 linear;
>
> + if (power_db > 96)
> + power_db = 96;
> + else if (power_db < 1)
> + return 1;
> +
> /* 1dB ~ 96dB */
> i = (power_db - 1) >> 3;
> j = (power_db - 1) - (i << 3);
> --

Thanks. For this patch.

Acked-by: Yan-Hsuan Chuang <[email protected]>

Yan-Hsuan

2019-05-06 08:44:08

by Stanislaw Gruszka

[permalink] [raw]
Subject: Re: [PATCH 5.1] rtw88: fix subscript above array bounds compiler warning

This is for 5.2 and v2 obviously.

Stanislaw

On Mon, May 06, 2019 at 09:39:17AM +0200, Stanislaw Gruszka wrote:
> My compiler complains about:
>
> drivers/net/wireless/realtek/rtw88/phy.c: In function ???rtw_phy_rf_power_2_rssi???:
> drivers/net/wireless/realtek/rtw88/phy.c:430:26: warning: array subscript is above array bounds [-Warray-bounds]
> linear = db_invert_table[i][j];
>
> According to comment power_db should be in range 1 ~ 96 .
> To fix add check for boundaries before access the array.
>
> Signed-off-by: Stanislaw Gruszka <[email protected]>
> ---
> RFC -> v1
> - add check before accessing the array insted of
> rtw_phy_power_2_db() change.
> v1 -> v2:
> - return 1 for power_db < 1
>
> drivers/net/wireless/realtek/rtw88/phy.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/net/wireless/realtek/rtw88/phy.c b/drivers/net/wireless/realtek/rtw88/phy.c
> index 4381b360b5b5..9ca52a4d025a 100644
> --- a/drivers/net/wireless/realtek/rtw88/phy.c
> +++ b/drivers/net/wireless/realtek/rtw88/phy.c
> @@ -423,6 +423,11 @@ static u64 rtw_phy_db_2_linear(u8 power_db)
> u8 i, j;
> u64 linear;
>
> + if (power_db > 96)
> + power_db = 96;
> + else if (power_db < 1)
> + return 1;
> +
> /* 1dB ~ 96dB */
> i = (power_db - 1) >> 3;
> j = (power_db - 1) - (i << 3);
> --
> 2.20.1
>

2019-05-28 11:32:51

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH 5.1] rtw88: fix subscript above array bounds compiler warning

Stanislaw Gruszka <[email protected]> wrote:

> My compiler complains about:
>
> drivers/net/wireless/realtek/rtw88/phy.c: In function ‘rtw_phy_rf_power_2_rssi’:
> drivers/net/wireless/realtek/rtw88/phy.c:430:26: warning: array subscript is above array bounds [-Warray-bounds]
> linear = db_invert_table[i][j];
>
> According to comment power_db should be in range 1 ~ 96 .
> To fix add check for boundaries before access the array.
>
> Signed-off-by: Stanislaw Gruszka <[email protected]>
> Acked-by: Yan-Hsuan Chuang <[email protected]>

Patch applied to wireless-drivers.git, thanks.

8a03447dd311 rtw88: fix subscript above array bounds compiler warning

--
https://patchwork.kernel.org/patch/10930671/

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