Re: [PATCH v3] mmc: tmio-mmc: fix bad pointer math

[Ulf Hansson]

On 12 July 2017 at 17:40, Chris Brandt  wrote:
> The existing code gives an incorrect pointer value.
> The buffer pointer 'buf' was of type unsigned short *, and 'count' was a
> number in bytes. A cast of buf should have been used.
>
> However, instead of casting, just change the code to use u32 pointers.
>
> Reported-by: Dan Carpenter 
> Fixes: 8185e51f358a: ("mmc: tmio-mmc: add support for 32bit data port")
> Signed-off-by: Chris Brandt 
> Reviewed-by: Geert Uytterhoeven 

Thanks, applied for fixes and added a stable tag.

Kind regards
Uffe

> ---
> v3:
>  * Merged lines
>  * Added Reviewed-by
> v2:
>  * Use u32 pointers instead of casting
> ---
>  drivers/mmc/host/tmio_mmc_core.c | 19 +--
>  1 file changed, 9 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/mmc/host/tmio_mmc_core.c 
> b/drivers/mmc/host/tmio_mmc_core.c
> index 77e7b56a9099..db779732fd2e 100644
> --- a/drivers/mmc/host/tmio_mmc_core.c
> +++ b/drivers/mmc/host/tmio_mmc_core.c
> @@ -415,30 +415,29 @@ static void tmio_mmc_transfer_data(struct tmio_mmc_host 
> *host,
>  * Transfer the data
>  */
> if (host->pdata->flags & TMIO_MMC_32BIT_DATA_PORT) {
> -   u8 data[4] = { };
> +   u32 data = 0;
> +   u32 *buf32 = (u32 *)buf;
>
> if (is_read)
> -   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT, (u32 *)buf,
> +   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT, buf32,
>count >> 2);
> else
> -   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT, (u32 
> *)buf,
> +   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT, buf32,
> count >> 2);
>
> /* if count was multiple of 4 */
> if (!(count & 0x3))
> return;
>
> -   buf8 = (u8 *)(buf + (count >> 2));
> +   buf32 += count >> 2;
> count %= 4;
>
> if (is_read) {
> -   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT,
> -  (u32 *)data, 1);
> -   memcpy(buf8, data, count);
> +   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT, , 1);
> +   memcpy(buf32, , count);
> } else {
> -   memcpy(data, buf8, count);
> -   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT,
> -   (u32 *)data, 1);
> +   memcpy(, buf32, count);
> +   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT, , 1);
> }
>
> return;
> --
> 2.13.0
>
>

Re: [PATCH v3] mmc: tmio-mmc: fix bad pointer math

[Wolfram Sang]

On Wed, Jul 12, 2017 at 08:40:01AM -0700, Chris Brandt wrote:
> The existing code gives an incorrect pointer value.
> The buffer pointer 'buf' was of type unsigned short *, and 'count' was a
> number in bytes. A cast of buf should have been used.
> 
> However, instead of casting, just change the code to use u32 pointers.
> 
> Reported-by: Dan Carpenter 
> Fixes: 8185e51f358a: ("mmc: tmio-mmc: add support for 32bit data port")
> Signed-off-by: Chris Brandt 
> Reviewed-by: Geert Uytterhoeven 

Acked-by: Wolfram Sang 



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[PATCH v3] mmc: tmio-mmc: fix bad pointer math

[Chris Brandt]

The existing code gives an incorrect pointer value.
The buffer pointer 'buf' was of type unsigned short *, and 'count' was a
number in bytes. A cast of buf should have been used.

However, instead of casting, just change the code to use u32 pointers.

Reported-by: Dan Carpenter 
Fixes: 8185e51f358a: ("mmc: tmio-mmc: add support for 32bit data port")
Signed-off-by: Chris Brandt 
Reviewed-by: Geert Uytterhoeven 
---
v3:
 * Merged lines
 * Added Reviewed-by
v2:
 * Use u32 pointers instead of casting
---
 drivers/mmc/host/tmio_mmc_core.c | 19 +--
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c
index 77e7b56a9099..db779732fd2e 100644
--- a/drivers/mmc/host/tmio_mmc_core.c
+++ b/drivers/mmc/host/tmio_mmc_core.c
@@ -415,30 +415,29 @@ static void tmio_mmc_transfer_data(struct tmio_mmc_host 
*host,
 * Transfer the data
 */
if (host->pdata->flags & TMIO_MMC_32BIT_DATA_PORT) {
-   u8 data[4] = { };
+   u32 data = 0;
+   u32 *buf32 = (u32 *)buf;
 
if (is_read)
-   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT, (u32 *)buf,
+   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT, buf32,
   count >> 2);
else
-   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT, (u32 *)buf,
+   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT, buf32,
count >> 2);
 
/* if count was multiple of 4 */
if (!(count & 0x3))
return;
 
-   buf8 = (u8 *)(buf + (count >> 2));
+   buf32 += count >> 2;
count %= 4;
 
if (is_read) {
-   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT,
-  (u32 *)data, 1);
-   memcpy(buf8, data, count);
+   sd_ctrl_read32_rep(host, CTL_SD_DATA_PORT, , 1);
+   memcpy(buf32, , count);
} else {
-   memcpy(data, buf8, count);
-   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT,
-   (u32 *)data, 1);
+   memcpy(, buf32, count);
+   sd_ctrl_write32_rep(host, CTL_SD_DATA_PORT, , 1);
}
 
return;
-- 
2.13.0