2015-11-06 15:18:52

by Ivan Safonov

Subject: [PATCH 2/3] staging: rtl8188eu: if/else replaced by min_t

Duplicated code removed.

Signed-off-by: Ivan Safonov <[email protected]>
---
drivers/staging/rtl8188eu/core/rtw_cmd.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/staging/rtl8188eu/core/rtw_cmd.c b/drivers/staging/rtl8188eu/core/rtw_cmd.c
index c0fff77..80c602e 100644
--- a/drivers/staging/rtl8188eu/core/rtw_cmd.c
+++ b/drivers/staging/rtl8188eu/core/rtw_cmd.c
@@ -446,10 +446,7 @@ u8 rtw_joinbss_cmd(struct adapter *padapter, struct wlan_network *pnetwork)

psecuritypriv->authenticator_ie[0] = (unsigned char)psecnetwork->IELength;

- if ((psecnetwork->IELength-12) < (256-1))
- memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], psecnetwork->IELength-12);
- else
- memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], (256-1));
+ memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], min_t(int, psecnetwork->IELength - 12, 256 - 1));

psecnetwork->IELength = 0;
/* Added by Albert 2009/02/18 */
--
2.4.10

2015-11-06 21:42:53

by Andy Shevchenko

Subject: Re: [PATCH 2/3] staging: rtl8188eu: if/else replaced by min_t

On Fri, Nov 6, 2015 at 5:18 PM, Ivan Safonov <[email protected]> wrote:
> Duplicated code removed.
>
> Signed-off-by: Ivan Safonov <[email protected]>
> ---
> drivers/staging/rtl8188eu/core/rtw_cmd.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/staging/rtl8188eu/core/rtw_cmd.c b/drivers/staging/rtl8188eu/core/rtw_cmd.c
> index c0fff77..80c602e 100644
> --- a/drivers/staging/rtl8188eu/core/rtw_cmd.c
> +++ b/drivers/staging/rtl8188eu/core/rtw_cmd.c
> @@ -446,10 +446,7 @@ u8 rtw_joinbss_cmd(struct adapter *padapter, struct wlan_network *pnetwork)
>
> psecuritypriv->authenticator_ie[0] = (unsigned char)psecnetwork->IELength;
>
> - if ((psecnetwork->IELength-12) < (256-1))
> - memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], psecnetwork->IELength-12);
> - else
> - memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], (256-1));
> + memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], min_t(int, psecnetwork->IELength - 12, 256 - 1));
>

Run checkpatch.pl.

256 looks like sizeof(…).

> psecnetwork->IELength = 0;
> /* Added by Albert 2009/02/18 */
> --
> 2.4.10
>
> --
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--
With Best Regards,
Andy Shevchenko

2015-11-06 21:58:20

by Dan Carpenter

Subject: Re: [PATCH 2/3] staging: rtl8188eu: if/else replaced by min_t

On Fri, Nov 06, 2015 at 11:42:50PM +0200, Andy Shevchenko wrote:
> On Fri, Nov 6, 2015 at 5:18 PM, Ivan Safonov <[email protected]> wrote:

> > psecuritypriv->authenticator_ie[0] = (unsigned char)psecnetwork->IELength;
> >
> > - if ((psecnetwork->IELength-12) < (256-1))
> > - memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], psecnetwork->IELength-12);
> > - else
> > - memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], (256-1));
> > + memcpy(&psecuritypriv->authenticator_ie[1], &psecnetwork->IEs[12], min_t(int, psecnetwork->IELength - 12, 256 - 1));
> >
>
> Run checkpatch.pl.

The long line was there in the original so it's forgivable but probably
should be changed in v2.

The main thing though is that this looks to introduce a memory
corruption but because the original used unsigned comparison and we have
changed it to doing "int" comparison. It should be u32 like in the
original code. Or size_t would be ok too.

>
> 256 looks like sizeof(…).

Yup.

regards,
dan carpenter