[PATCH 1/1] comedi: ni_usb6501: fix transfer-buffer overflows

[PATCH 1/1] comedi: ni_usb6501: fix transfer-buffer overflows

[Xiaohui Zhang]

Similar to the handling of vmk80xx_alloc_usb_buffers in commit
a23461c47482("comedi: vmk80xx: fix transfer-buffer overflows"),
we thought a patch might be needed here as well.

The driver uses endpoint-sized USB transfer buffers but up until
recently had no sanity checks on the sizes.

Signed-off-by: Xiaohui Zhang <xiaohuizhang@ruc.edu.cn>
---
 drivers/comedi/drivers/ni_usb6501.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/comedi/drivers/ni_usb6501.c b/drivers/comedi/drivers/ni_usb6501.c
index 0dd9edf7bced..8303bfc305c5 100644
--- a/drivers/comedi/drivers/ni_usb6501.c
+++ b/drivers/comedi/drivers/ni_usb6501.c
@@ -90,6 +90,7 @@
 #include <linux/comedi/comedi_usb.h>
 
 #define	NI6501_TIMEOUT	1000
+#define MIN_BUF_SIZE	64
 
 /* Port request packets */
 static const u8 READ_PORT_REQUEST[]	= {0x00, 0x01, 0x00, 0x10,
@@ -459,12 +460,12 @@ static int ni6501_alloc_usb_buffers(struct comedi_device *dev)
 	struct ni6501_private *devpriv = dev->private;
 	size_t size;
 
-	size = usb_endpoint_maxp(devpriv->ep_rx);
+	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
 	devpriv->usb_rx_buf = kzalloc(size, GFP_KERNEL);
 	if (!devpriv->usb_rx_buf)
 		return -ENOMEM;
 
-	size = usb_endpoint_maxp(devpriv->ep_tx);
+	size = max(usb_endpoint_maxp(devpriv->ep_tx), MIN_BUF_SIZE);
 	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
 	if (!devpriv->usb_tx_buf)
 		return -ENOMEM;
-- 
2.17.1

Re: [PATCH 1/1] comedi: ni_usb6501: fix transfer-buffer overflows

[Ian Abbott]

On 07/06/2022 12:18, Xiaohui Zhang wrote:
> Similar to the handling of vmk80xx_alloc_usb_buffers in commit
> a23461c47482("comedi: vmk80xx: fix transfer-buffer overflows"),
> we thought a patch might be needed here as well.
> 
> The driver uses endpoint-sized USB transfer buffers but up until
> recently had no sanity checks on the sizes.
> 
> Signed-off-by: Xiaohui Zhang <xiaohuizhang@ruc.edu.cn>
> ---
>   drivers/comedi/drivers/ni_usb6501.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/comedi/drivers/ni_usb6501.c b/drivers/comedi/drivers/ni_usb6501.c
> index 0dd9edf7bced..8303bfc305c5 100644
> --- a/drivers/comedi/drivers/ni_usb6501.c
> +++ b/drivers/comedi/drivers/ni_usb6501.c
> @@ -90,6 +90,7 @@
>   #include <linux/comedi/comedi_usb.h>
>   
>   #define	NI6501_TIMEOUT	1000
> +#define MIN_BUF_SIZE	64
>   
>   /* Port request packets */
>   static const u8 READ_PORT_REQUEST[]	= {0x00, 0x01, 0x00, 0x10,
> @@ -459,12 +460,12 @@ static int ni6501_alloc_usb_buffers(struct comedi_device *dev)
>   	struct ni6501_private *devpriv = dev->private;
>   	size_t size;
>   
> -	size = usb_endpoint_maxp(devpriv->ep_rx);
> +	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
>   	devpriv->usb_rx_buf = kzalloc(size, GFP_KERNEL);
>   	if (!devpriv->usb_rx_buf)
>   		return -ENOMEM;
>   
> -	size = usb_endpoint_maxp(devpriv->ep_tx);
> +	size = max(usb_endpoint_maxp(devpriv->ep_tx), MIN_BUF_SIZE);
>   	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
>   	if (!devpriv->usb_tx_buf)
>   		return -ENOMEM;

The code change looks OK but this patch should have been sent as a "v2" 
patch and should have a brief description of the v2 changes after the 
"---" line.

Reviewed-by: Ian Abbott <abbotti@mev.co.uk>

-- 
-=( Ian Abbott <abbotti@mev.co.uk> || MEV Ltd. is a company  )=-
-=( registered in England & Wales.  Regd. number: 02862268.  )=-
-=( Regd. addr.: S11 & 12 Building 67, Europa Business Park, )=-
-=( Bird Hall Lane, STOCKPORT, SK3 0XA, UK. || www.mev.co.uk )=-

Re: [PATCH 1/1] comedi: ni_usb6501: fix transfer-buffer overflows

[Greg Kroah-Hartman]

On Tue, Jun 07, 2022 at 07:18:02PM +0800, Xiaohui Zhang wrote:
> Similar to the handling of vmk80xx_alloc_usb_buffers in commit
> a23461c47482("comedi: vmk80xx: fix transfer-buffer overflows"),
> we thought a patch might be needed here as well.
> 
> The driver uses endpoint-sized USB transfer buffers but up until
> recently had no sanity checks on the sizes.
> 
> Signed-off-by: Xiaohui Zhang <xiaohuizhang@ruc.edu.cn>
> ---
>  drivers/comedi/drivers/ni_usb6501.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/comedi/drivers/ni_usb6501.c b/drivers/comedi/drivers/ni_usb6501.c
> index 0dd9edf7bced..8303bfc305c5 100644
> --- a/drivers/comedi/drivers/ni_usb6501.c
> +++ b/drivers/comedi/drivers/ni_usb6501.c
> @@ -90,6 +90,7 @@
>  #include <linux/comedi/comedi_usb.h>
>  
>  #define	NI6501_TIMEOUT	1000
> +#define MIN_BUF_SIZE	64
>  
>  /* Port request packets */
>  static const u8 READ_PORT_REQUEST[]	= {0x00, 0x01, 0x00, 0x10,
> @@ -459,12 +460,12 @@ static int ni6501_alloc_usb_buffers(struct comedi_device *dev)
>  	struct ni6501_private *devpriv = dev->private;
>  	size_t size;
>  
> -	size = usb_endpoint_maxp(devpriv->ep_rx);
> +	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
>  	devpriv->usb_rx_buf = kzalloc(size, GFP_KERNEL);
>  	if (!devpriv->usb_rx_buf)
>  		return -ENOMEM;
>  
> -	size = usb_endpoint_maxp(devpriv->ep_tx);
> +	size = max(usb_endpoint_maxp(devpriv->ep_tx), MIN_BUF_SIZE);
>  	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
>  	if (!devpriv->usb_tx_buf)
>  		return -ENOMEM;
> -- 
> 2.17.1
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- You did not specify a description of why the patch is needed, or
  possibly, any description at all, in the email body.  Please read the
  section entitled "The canonical patch format" in the kernel file,
  Documentation/SubmittingPatches for what is needed in order to
  properly describe the change.

- You did not write a descriptive Subject: for the patch, allowing Greg,
  and everyone else, to know what this patch is all about.  Please read
  the section entitled "The canonical patch format" in the kernel file,
  Documentation/SubmittingPatches for what a proper Subject: line should
  look like.

- This looks like a new version of a previously submitted patch, but you
  did not list below the --- line any changes from the previous version.
  Please read the section entitled "The canonical patch format" in the
  kernel file, Documentation/SubmittingPatches for what needs to be done
  here to properly describe this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.

thanks,

greg k-h's patch email bot

Re: [PATCH 1/1] comedi: ni_usb6501: fix transfer-buffer overflows

[Ian Abbott]

On 05/06/2022 13:43, Xiaohui Zhang wrote:
> From: xiaohuizhang98 <ruc_zhangxiaohui@163.com>
> 
> We detected a suspected bug with our code clone detection tool.
> 
> Similar to the handling of vmk80xx_alloc_usb_buffers in commit
> a23461c47482("comedi: vmk80xx: fix transfer-buffer overflows"),
> we thought a patch might be needed here as well.
> 
> The driver uses endpoint-sized USB transfer buffers but up until
> recently had no sanity checks on the sizes.
> 
> Signed-off-by: xiaohuizhang98 <ruc_zhangxiaohui@163.com>
> ---
>   drivers/comedi/drivers/ni_usb6501.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/comedi/drivers/ni_usb6501.c b/drivers/comedi/drivers/ni_usb6501.c
> index 0dd9edf7bced..3e2b9f4d840b 100644
> --- a/drivers/comedi/drivers/ni_usb6501.c
> +++ b/drivers/comedi/drivers/ni_usb6501.c
> @@ -90,6 +90,7 @@
>   #include <linux/comedi/comedi_usb.h>
>   
>   #define	NI6501_TIMEOUT	1000
> +#define MIN_BUF_SIZE	64
>   
>   /* Port request packets */
>   static const u8 READ_PORT_REQUEST[]	= {0x00, 0x01, 0x00, 0x10,
> @@ -459,12 +460,12 @@ static int ni6501_alloc_usb_buffers(struct comedi_device *dev)
>   	struct ni6501_private *devpriv = dev->private;
>   	size_t size;
>   
> -	size = usb_endpoint_maxp(devpriv->ep_rx);
> +	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
>   	devpriv->usb_rx_buf = kzalloc(size, GFP_KERNEL);
>   	if (!devpriv->usb_rx_buf)
>   		return -ENOMEM;
>   
> -	size = usb_endpoint_maxp(devpriv->ep_tx);
> +	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
>   	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
>   	if (!devpriv->usb_tx_buf)
>   		return -ENOMEM;

Actually, there is a typo in the last bit of the patch that was copied 
from the similar patch to vmk80xx.  It is using the wrong endpoint to 
determine the size for usb_tx_buf.

-- 
-=( Ian Abbott <abbotti@mev.co.uk> || MEV Ltd. is a company  )=-
-=( registered in England & Wales.  Regd. number: 02862268.  )=-
-=( Regd. addr.: S11 & 12 Building 67, Europa Business Park, )=-
-=( Bird Hall Lane, STOCKPORT, SK3 0XA, UK. || www.mev.co.uk )=-

Re: [PATCH 1/1] comedi: ni_usb6501: fix transfer-buffer overflows

[Greg Kroah-Hartman]

On Sun, Jun 05, 2022 at 08:43:22PM +0800, Xiaohui Zhang wrote:
> From: xiaohuizhang98 <ruc_zhangxiaohui@163.com>
> 
> We detected a suspected bug with our code clone detection tool.

What tool exactly?

Please read Documentation/process/researcher-guidelines.rst for how to
write a good changelog when you are using automated tools like this.

> 
> Similar to the handling of vmk80xx_alloc_usb_buffers in commit
> a23461c47482("comedi: vmk80xx: fix transfer-buffer overflows"),
> we thought a patch might be needed here as well.
> 
> The driver uses endpoint-sized USB transfer buffers but up until
> recently had no sanity checks on the sizes.
> 
> Signed-off-by: xiaohuizhang98 <ruc_zhangxiaohui@163.com>

I strongly doubt you sign legal documents like "xiaohuizhang98", right?

thanks,

greg k-h

[PATCH 1/1] comedi: ni_usb6501: fix transfer-buffer overflows

[Xiaohui Zhang]

From: xiaohuizhang98 <ruc_zhangxiaohui@163.com>

We detected a suspected bug with our code clone detection tool.

Similar to the handling of vmk80xx_alloc_usb_buffers in commit
a23461c47482("comedi: vmk80xx: fix transfer-buffer overflows"),
we thought a patch might be needed here as well.

The driver uses endpoint-sized USB transfer buffers but up until
recently had no sanity checks on the sizes.

Signed-off-by: xiaohuizhang98 <ruc_zhangxiaohui@163.com>
---
 drivers/comedi/drivers/ni_usb6501.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/comedi/drivers/ni_usb6501.c b/drivers/comedi/drivers/ni_usb6501.c
index 0dd9edf7bced..3e2b9f4d840b 100644
--- a/drivers/comedi/drivers/ni_usb6501.c
+++ b/drivers/comedi/drivers/ni_usb6501.c
@@ -90,6 +90,7 @@
 #include <linux/comedi/comedi_usb.h>
 
 #define	NI6501_TIMEOUT	1000
+#define MIN_BUF_SIZE	64
 
 /* Port request packets */
 static const u8 READ_PORT_REQUEST[]	= {0x00, 0x01, 0x00, 0x10,
@@ -459,12 +460,12 @@ static int ni6501_alloc_usb_buffers(struct comedi_device *dev)
 	struct ni6501_private *devpriv = dev->private;
 	size_t size;
 
-	size = usb_endpoint_maxp(devpriv->ep_rx);
+	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
 	devpriv->usb_rx_buf = kzalloc(size, GFP_KERNEL);
 	if (!devpriv->usb_rx_buf)
 		return -ENOMEM;
 
-	size = usb_endpoint_maxp(devpriv->ep_tx);
+	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
 	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
 	if (!devpriv->usb_tx_buf)
 		return -ENOMEM;
-- 
2.17.1