[PATCH v2] usb: gadget: aspeed_udc: Add check for dma_alloc_coherent

[PATCH v2] usb: gadget: aspeed_udc: Add check for dma_alloc_coherent

[Jiasheng Jiang]

Add the check for the return value of dma_alloc_coherent
in order to avoid NULL pointer dereference.

Fixes: 055276c13205 ("usb: gadget: add Aspeed ast2600 udc driver")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
Changelog:

v1 -> v2:

1. Add "goto err;" when allocation fails.
---
 drivers/usb/gadget/udc/aspeed_udc.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
index 01968e2167f9..7dc2457c7460 100644
--- a/drivers/usb/gadget/udc/aspeed_udc.c
+++ b/drivers/usb/gadget/udc/aspeed_udc.c
@@ -1516,6 +1516,10 @@ static int ast_udc_probe(struct platform_device *pdev)
 					  AST_UDC_EP_DMA_SIZE *
 					  AST_UDC_NUM_ENDPOINTS,
 					  &udc->ep0_buf_dma, GFP_KERNEL);
+	if (!udc->ep0_buf) {
+		rc = -ENOMEM;
+		goto err;
+	}
 
 	udc->gadget.speed = USB_SPEED_UNKNOWN;
 	udc->gadget.max_speed = USB_SPEED_HIGH;
-- 
2.25.1

[PATCH v2] usb: gadget: aspeed_udc: Add check for dma_alloc_coherent

[Greg KH]

On Tue, Dec 13, 2022 at 08:21:16PM +0800, Jiasheng Jiang wrote:
> Add the check for the return value of dma_alloc_coherent
> in order to avoid NULL pointer dereference.
> 
> Fixes: 055276c13205 ("usb: gadget: add Aspeed ast2600 udc driver")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>

Again, please prove that you tested this and follow the requirements at:
	Documentation/process/researcher-guidelines.rst
in order for us to be able to accept your changes.

thanks,

greg k-h

[PATCH v2] usb: gadget: aspeed_udc: Add check for dma_alloc_coherent

[Jiasheng Jiang]

Add the check for the return value of dma_alloc_coherent in order to
avoid NULL pointer dereference.

This flaw was found using an experimental static analysis tool we are
developing, APP-Miner, which has not been disclosed.

The allyesconfig build using GCC 9.3.0 shows no new warning. As we
don't have a UDC device to test with, no runtime testing was able to
be performed.

Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
Changelog:

v1 -> v2:

1. Add "goto err;" when allocation fails.
---
 drivers/usb/gadget/udc/aspeed_udc.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/gadget/udc/aspeed_udc.c b/drivers/usb/gadget/udc/aspeed_udc.c
index 01968e2167f9..7dc2457c7460 100644
--- a/drivers/usb/gadget/udc/aspeed_udc.c
+++ b/drivers/usb/gadget/udc/aspeed_udc.c
@@ -1516,6 +1516,10 @@ static int ast_udc_probe(struct platform_device *pdev)
 					  AST_UDC_EP_DMA_SIZE *
 					  AST_UDC_NUM_ENDPOINTS,
 					  &udc->ep0_buf_dma, GFP_KERNEL);
+	if (!udc->ep0_buf) {
+		rc = -ENOMEM;
+		goto err;
+	}
 
 	udc->gadget.speed = USB_SPEED_UNKNOWN;
 	udc->gadget.max_speed = USB_SPEED_HIGH;
-- 
2.25.1

[PATCH v2] usb: gadget: aspeed_udc: Add check for dma_alloc_coherent

[Greg KH]

On Wed, Dec 14, 2022 at 10:54:14AM +0800, Jiasheng Jiang wrote:
> Add the check for the return value of dma_alloc_coherent in order to
> avoid NULL pointer dereference.
> 
> This flaw was found using an experimental static analysis tool we are
> developing, APP-Miner, which has not been disclosed.
> 
> The allyesconfig build using GCC 9.3.0 shows no new warning. As we
> don't have a UDC device to test with, no runtime testing was able to
> be performed.
> 
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
> Changelog:
> 
> v1 -> v2:
> 
> 1. Add "goto err;" when allocation fails.

You already sent a previous v2 that differs from this one, this should
be v3, right?