2017-12-10 20:02:16

by Nicolas Iooss

[permalink] [raw]
Subject: [PATCH 1/1] rtlwifi: always initialize variables given to RT_TRACE()

In rtl_rx_ampdu_apply(), when rtlpriv->cfg->ops->get_btc_status()
returns false, RT_TRACE() is called with the values of variables
reject_agg and agg_size, which have not been initialized.

Always initialize these variables in order to prevent using
uninitialized values.

This issue has been found with clang. The compiler reported:

drivers/net/wireless/realtek/rtlwifi/base.c:1665:6: error: variable
'agg_size' is used uninitialized whenever 'if' condition is false
[-Werror,-Wsometimes-uninitialized]
if (rtlpriv->cfg->ops->get_btc_status())
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/realtek/rtlwifi/base.c:1671:31: note:
uninitialized use occurs here
reject_agg, ctrl_agg_size, agg_size);
^~~~~~~~

drivers/net/wireless/realtek/rtlwifi/base.c:1665:6: error: variable
'reject_agg' is used uninitialized whenever 'if' condition
is false [-Werror,-Wsometimes-uninitialized]
if (rtlpriv->cfg->ops->get_btc_status())
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/realtek/rtlwifi/base.c:1671:4: note:
uninitialized use occurs here
reject_agg, ctrl_agg_size, agg_size);
^~~~~~~~~~

Fixes: 2635664e6e4a ("rtlwifi: Add rx ampdu cfg for btcoexist.")
Signed-off-by: Nicolas Iooss <[email protected]>
---
drivers/net/wireless/realtek/rtlwifi/base.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtlwifi/base.c b/drivers/net/wireless/realtek/rtlwifi/base.c
index cad2272ae21b..704741d6f495 100644
--- a/drivers/net/wireless/realtek/rtlwifi/base.c
+++ b/drivers/net/wireless/realtek/rtlwifi/base.c
@@ -1726,7 +1726,7 @@ int rtl_tx_agg_oper(struct ieee80211_hw *hw,
void rtl_rx_ampdu_apply(struct rtl_priv *rtlpriv)
{
struct rtl_btc_ops *btc_ops = rtlpriv->btcoexist.btc_ops;
- u8 reject_agg, ctrl_agg_size = 0, agg_size;
+ u8 reject_agg = 0, ctrl_agg_size = 0, agg_size = 0;

if (rtlpriv->cfg->ops->get_btc_status())
btc_ops->btc_get_ampdu_cfg(rtlpriv, &reject_agg,
--
2.15.0


2017-12-14 12:44:14

by Kalle Valo

[permalink] [raw]
Subject: Re: [1/1] rtlwifi: always initialize variables given to RT_TRACE()

Nicolas Iooss <[email protected]> wrote:

> In rtl_rx_ampdu_apply(), when rtlpriv->cfg->ops->get_btc_status()
> returns false, RT_TRACE() is called with the values of variables
> reject_agg and agg_size, which have not been initialized.
>
> Always initialize these variables in order to prevent using
> uninitialized values.
>
> This issue has been found with clang. The compiler reported:
>
> drivers/net/wireless/realtek/rtlwifi/base.c:1665:6: error: variable
> 'agg_size' is used uninitialized whenever 'if' condition is false
> [-Werror,-Wsometimes-uninitialized]
> if (rtlpriv->cfg->ops->get_btc_status())
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/realtek/rtlwifi/base.c:1671:31: note:
> uninitialized use occurs here
> reject_agg, ctrl_agg_size, agg_size);
> ^~~~~~~~
>
> drivers/net/wireless/realtek/rtlwifi/base.c:1665:6: error: variable
> 'reject_agg' is used uninitialized whenever 'if' condition
> is false [-Werror,-Wsometimes-uninitialized]
> if (rtlpriv->cfg->ops->get_btc_status())
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/realtek/rtlwifi/base.c:1671:4: note:
> uninitialized use occurs here
> reject_agg, ctrl_agg_size, agg_size);
> ^~~~~~~~~~
>
> Fixes: 2635664e6e4a ("rtlwifi: Add rx ampdu cfg for btcoexist.")
> Signed-off-by: Nicolas Iooss <[email protected]>

Patch applied to wireless-drivers-next.git, thanks.

e4779162f737 rtlwifi: always initialize variables given to RT_TRACE()

--
https://patchwork.kernel.org/patch/10103995/

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

2017-12-11 17:35:01

by Larry Finger

[permalink] [raw]
Subject: Re: [PATCH 1/1] rtlwifi: always initialize variables given to RT_TRACE()

On 12/10/2017 01:51 PM, Nicolas Iooss wrote:
> In rtl_rx_ampdu_apply(), when rtlpriv->cfg->ops->get_btc_status()
> returns false, RT_TRACE() is called with the values of variables
> reject_agg and agg_size, which have not been initialized.
>
> Always initialize these variables in order to prevent using
> uninitialized values.
>
> This issue has been found with clang. The compiler reported:
>
> drivers/net/wireless/realtek/rtlwifi/base.c:1665:6: error: variable
> 'agg_size' is used uninitialized whenever 'if' condition is false
> [-Werror,-Wsometimes-uninitialized]
> if (rtlpriv->cfg->ops->get_btc_status())
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/realtek/rtlwifi/base.c:1671:31: note:
> uninitialized use occurs here
> reject_agg, ctrl_agg_size, agg_size);
> ^~~~~~~~
>
> drivers/net/wireless/realtek/rtlwifi/base.c:1665:6: error: variable
> 'reject_agg' is used uninitialized whenever 'if' condition
> is false [-Werror,-Wsometimes-uninitialized]
> if (rtlpriv->cfg->ops->get_btc_status())
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/realtek/rtlwifi/base.c:1671:4: note:
> uninitialized use occurs here
> reject_agg, ctrl_agg_size, agg_size);
> ^~~~~~~~~~
>
> Fixes: 2635664e6e4a ("rtlwifi: Add rx ampdu cfg for btcoexist.")
> Signed-off-by: Nicolas Iooss <[email protected]>

Looks good. Acked-by: Larry Finger <[email protected]>

Thanks,

Larry

> ---
> drivers/net/wireless/realtek/rtlwifi/base.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/realtek/rtlwifi/base.c b/drivers/net/wireless/realtek/rtlwifi/base.c
> index cad2272ae21b..704741d6f495 100644
> --- a/drivers/net/wireless/realtek/rtlwifi/base.c
> +++ b/drivers/net/wireless/realtek/rtlwifi/base.c
> @@ -1726,7 +1726,7 @@ int rtl_tx_agg_oper(struct ieee80211_hw *hw,
> void rtl_rx_ampdu_apply(struct rtl_priv *rtlpriv)
> {
> struct rtl_btc_ops *btc_ops = rtlpriv->btcoexist.btc_ops;
> - u8 reject_agg, ctrl_agg_size = 0, agg_size;
> + u8 reject_agg = 0, ctrl_agg_size = 0, agg_size = 0;
>
> if (rtlpriv->cfg->ops->get_btc_status())
> btc_ops->btc_get_ampdu_cfg(rtlpriv, &reject_agg,
>