[PATCH] Input: synaptics-rmi4 - Fix an unchecked out of memory error path

[PATCH] Input: synaptics-rmi4 - Fix an unchecked out of memory error path

[Christophe JAILLET]

When extending the rmi_spi buffers, we must check that no out of memory
error occurs, otherwise we may access data above the currently allocated
memory.

Propagate the error code returned by 'rmi_spi_manage_pools()' instead.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/input/rmi4/rmi_spi.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/input/rmi4/rmi_spi.c b/drivers/input/rmi4/rmi_spi.c
index 76edbf2c1bce..082defc329a8 100644
--- a/drivers/input/rmi4/rmi_spi.c
+++ b/drivers/input/rmi4/rmi_spi.c
@@ -147,8 +147,11 @@ static int rmi_spi_xfer(struct rmi_spi_xport *rmi_spi,
 	if (len > RMI_SPI_XFER_SIZE_LIMIT)
 		return -EINVAL;
 
-	if (rmi_spi->xfer_buf_size < len)
-		rmi_spi_manage_pools(rmi_spi, len);
+	if (rmi_spi->xfer_buf_size < len) {
+		ret = rmi_spi_manage_pools(rmi_spi, len);
+		if (ret < 0)
+			return ret;
+	}
 
 	if (addr == 0)
 		/*
-- 
2.14.1

Re: [PATCH] Input: synaptics-rmi4 - Fix an unchecked out of memory error path

[Andrew Duggan]

On 04/02/2018 07:03 AM, Christophe JAILLET wrote:
> When extending the rmi_spi buffers, we must check that no out of memory
> error occurs, otherwise we may access data above the currently allocated
> memory.
>
> Propagate the error code returned by 'rmi_spi_manage_pools()' instead.
Yep, that definitely looks like an oversight on my part. Thanks for the fix.

Andrew

> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

Reviewed-by: Andrew Duggan <aduggan@synaptics.com>

> ---
>   drivers/input/rmi4/rmi_spi.c | 7 +++++--
>   1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/input/rmi4/rmi_spi.c b/drivers/input/rmi4/rmi_spi.c
> index 76edbf2c1bce..082defc329a8 100644
> --- a/drivers/input/rmi4/rmi_spi.c
> +++ b/drivers/input/rmi4/rmi_spi.c
> @@ -147,8 +147,11 @@ static int rmi_spi_xfer(struct rmi_spi_xport *rmi_spi,
>   	if (len > RMI_SPI_XFER_SIZE_LIMIT)
>   		return -EINVAL;
>   
> -	if (rmi_spi->xfer_buf_size < len)
> -		rmi_spi_manage_pools(rmi_spi, len);
> +	if (rmi_spi->xfer_buf_size < len) {
> +		ret = rmi_spi_manage_pools(rmi_spi, len);
> +		if (ret < 0)
> +			return ret;
> +	}
>   
>   	if (addr == 0)
>   		/*

Re: [PATCH] Input: synaptics-rmi4 - Fix an unchecked out of memory error path

[Dmitry Torokhov]

On Mon, Apr 02, 2018 at 05:52:52PM -0700, Andrew Duggan wrote:
> 
> On 04/02/2018 07:03 AM, Christophe JAILLET wrote:
> > When extending the rmi_spi buffers, we must check that no out of memory
> > error occurs, otherwise we may access data above the currently allocated
> > memory.
> > 
> > Propagate the error code returned by 'rmi_spi_manage_pools()' instead.
> Yep, that definitely looks like an oversight on my part. Thanks for the fix.
> 
> Andrew
> 
> > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> 
> Reviewed-by: Andrew Duggan <aduggan@synaptics.com>

Applied, thank you.

> 
> > ---
> >   drivers/input/rmi4/rmi_spi.c | 7 +++++--
> >   1 file changed, 5 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/input/rmi4/rmi_spi.c b/drivers/input/rmi4/rmi_spi.c
> > index 76edbf2c1bce..082defc329a8 100644
> > --- a/drivers/input/rmi4/rmi_spi.c
> > +++ b/drivers/input/rmi4/rmi_spi.c
> > @@ -147,8 +147,11 @@ static int rmi_spi_xfer(struct rmi_spi_xport *rmi_spi,
> >   	if (len > RMI_SPI_XFER_SIZE_LIMIT)
> >   		return -EINVAL;
> > -	if (rmi_spi->xfer_buf_size < len)
> > -		rmi_spi_manage_pools(rmi_spi, len);
> > +	if (rmi_spi->xfer_buf_size < len) {
> > +		ret = rmi_spi_manage_pools(rmi_spi, len);
> > +		if (ret < 0)
> > +			return ret;
> > +	}
> >   	if (addr == 0)
> >   		/*
> 

-- 
Dmitry

Re: [PATCH] Input: synaptics-rmi4 - Fix an unchecked out of memory error path

[Sasha Levin]

Hi Christophe JAILLET.

[This is an automated email]

This commit has been processed by the -stable helper bot and determined
to be a high probability candidate for -stable trees. (score: 7.5278)

The bot has tested the following trees: v4.15.15, v4.14.32, v4.9.92, v4.4.126, 

v4.15.15: Build OK!
v4.14.32: Build OK!
v4.9.92: Build OK!
v4.4.126: Failed to apply! Possible dependencies:
    8d99758dee31: ("Input: synaptics-rmi4 - add SPI transport driver")
    ff8f83708b3e: ("Input: synaptics-rmi4 - add support for 2D sensors and F11")
    fdf51604f104: ("Input: synaptics-rmi4 - add I2C transport driver")
    2b6a321da9a2: ("Input: synaptics-rmi4 - add support for Synaptics RMI4 devices")
    2b6a321da9a2: ("Input: synaptics-rmi4 - add support for Synaptics RMI4 devices")
    fdf51604f104: ("Input: synaptics-rmi4 - add I2C transport driver")
    2b6a321da9a2: ("Input: synaptics-rmi4 - add support for Synaptics RMI4 devices")
    2b6a321da9a2: ("Input: synaptics-rmi4 - add support for Synaptics RMI4 devices")


Please let us know if you'd like to have this patch included in a stable tree.

--
Thanks.
Sasha