[PATCH v2] nvmem/mxs-ocotp: fix buffer overflow in read

[PATCH v2] nvmem/mxs-ocotp: fix buffer overflow in read

[Stanislav Meduna]

This patch fixes the issue where the mxs_ocotp_read is reading
the ocotp in reg_size steps but decrements the remaining size
by 1. The number of iterations is thus four times higher,
overwriting the area behind the output buffer.

Fixes: c01e9a11ab6f ("nvmem: add driver for ocotp in i.MX23 and i.MX28")
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Stanislav Meduna <stano@meduna.org>
---
 drivers/nvmem/mxs-ocotp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/nvmem/mxs-ocotp.c b/drivers/nvmem/mxs-ocotp.c
index 8ba19bb..2bb3c57 100644
--- a/drivers/nvmem/mxs-ocotp.c
+++ b/drivers/nvmem/mxs-ocotp.c
@@ -94,7 +94,7 @@ static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size,
 	if (ret)
 		goto close_banks;

-	while (val_size) {
+	while (val_size >= reg_size) {
 		if ((offset < OCOTP_DATA_OFFSET) || (offset % 16)) {
 			/* fill up non-data register */
 			*buf = 0;
@@ -103,7 +103,7 @@ static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size,
 		}

 		buf++;
-		val_size--;
+		val_size -= reg_size;
 		offset += reg_size;
 	}

-- 
2.1.4

[PATCH v2] nvmem/mxs-ocotp: fix buffer overflow in read

[Stefan Wahren]

Hi Srinivas,
hi Greg,

Am 27.04.2016 um 14:39 schrieb Stanislav Meduna:
> This patch fixes the issue where the mxs_ocotp_read is reading
> the ocotp in reg_size steps but decrements the remaining size
> by 1. The number of iterations is thus four times higher,
> overwriting the area behind the output buffer.
>
> Fixes: c01e9a11ab6f ("nvmem: add driver for ocotp in i.MX23 and i.MX28")
> Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
> Signed-off-by: Stanislav Meduna <stano@meduna.org>

any change to get this critical fix into 4.6?

Regards
Stefan

> ---
>  drivers/nvmem/mxs-ocotp.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/nvmem/mxs-ocotp.c b/drivers/nvmem/mxs-ocotp.c
> index 8ba19bb..2bb3c57 100644
> --- a/drivers/nvmem/mxs-ocotp.c
> +++ b/drivers/nvmem/mxs-ocotp.c
> @@ -94,7 +94,7 @@ static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size,
>  	if (ret)
>  		goto close_banks;
>
> -	while (val_size) {
> +	while (val_size >= reg_size) {
>  		if ((offset < OCOTP_DATA_OFFSET) || (offset % 16)) {
>  			/* fill up non-data register */
>  			*buf = 0;
> @@ -103,7 +103,7 @@ static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size,
>  		}
>
>  		buf++;
> -		val_size--;
> +		val_size -= reg_size;
>  		offset += reg_size;
>  	}
>

[PATCH v2] nvmem/mxs-ocotp: fix buffer overflow in read

[Greg Kroah-Hartman]

On Mon, May 02, 2016 at 03:55:53PM +0200, Stefan Wahren wrote:
> Hi Srinivas,
> hi Greg,
> 
> Am 27.04.2016 um 14:39 schrieb Stanislav Meduna:
> > This patch fixes the issue where the mxs_ocotp_read is reading
> > the ocotp in reg_size steps but decrements the remaining size
> > by 1. The number of iterations is thus four times higher,
> > overwriting the area behind the output buffer.
> >
> > Fixes: c01e9a11ab6f ("nvmem: add driver for ocotp in i.MX23 and i.MX28")
> > Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
> > Signed-off-by: Stanislav Meduna <stano@meduna.org>
> 
> any change to get this critical fix into 4.6?

This is the first I've seen this patch :(

Can you resend it in a format I can apply it in?

thanks,

greg k-h

[PATCH v2] nvmem/mxs-ocotp: fix buffer overflow in read

[Stefan Wahren]

Hi Stano,

Am 02.05.2016 um 16:44 schrieb Greg Kroah-Hartman:
> On Mon, May 02, 2016 at 03:55:53PM +0200, Stefan Wahren wrote:
>> Hi Srinivas,
>> hi Greg,
>>
>> Am 27.04.2016 um 14:39 schrieb Stanislav Meduna:
>>> This patch fixes the issue where the mxs_ocotp_read is reading
>>> the ocotp in reg_size steps but decrements the remaining size
>>> by 1. The number of iterations is thus four times higher,
>>> overwriting the area behind the output buffer.
>>>
>>> Fixes: c01e9a11ab6f ("nvmem: add driver for ocotp in i.MX23 and i.MX28")
>>> Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
>>> Signed-off-by: Stanislav Meduna <stano@meduna.org>
>> any change to get this critical fix into 4.6?
> This is the first I've seen this patch :(

sorry for this.

>
> Can you resend it in a format I can apply it in?

Could you please resend V2 to Greg?

Thanks
Stefan

>
> thanks,
>
> greg k-h
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v2] nvmem/mxs-ocotp: fix buffer overflow in read

[Srinivas Kandagatla]

Hi Stefan,


On 02/05/16 15:50, Stefan Wahren wrote:
> Hi Stano,
>
> Am 02.05.2016 um 16:44 schrieb Greg Kroah-Hartman:
>> On Mon, May 02, 2016 at 03:55:53PM +0200, Stefan Wahren wrote:
>>> Hi Srinivas,
>>> hi Greg,
>>>
>>> Am 27.04.2016 um 14:39 schrieb Stanislav Meduna:
>>>> This patch fixes the issue where the mxs_ocotp_read is reading
>>>> the ocotp in reg_size steps but decrements the remaining size
>>>> by 1. The number of iterations is thus four times higher,
>>>> overwriting the area behind the output buffer.
>>>>
>>>> Fixes: c01e9a11ab6f ("nvmem: add driver for ocotp in i.MX23 and i.MX28")
>>>> Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
>>>> Signed-off-by: Stanislav Meduna <stano@meduna.org>
>>> any change to get this critical fix into 4.6?
>> This is the first I've seen this patch :(
>
> sorry for this.
>
>>
>> Can you resend it in a format I can apply it in?
>
> Could you please resend V2 to Greg?

I will re-send this patch to Greg in next few mins..

thanks,
srini

>
> Thanks
> Stefan
>
>>
>> thanks,
>>
>> greg k-h
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>