diff mbox series

[v2] dmaengine: ti: edma: fix OF node reference leaks in edma_driver

Message ID 20241218011520.2579828-1-joe@pf.is.s.u-tokyo.ac.jp (mailing list archive)
State Superseded
Headers show
Series [v2] dmaengine: ti: edma: fix OF node reference leaks in edma_driver | expand

Commit Message

Joe Hattori Dec. 18, 2024, 1:15 a.m. UTC
The .probe() of edma_driver calls of_parse_phandle_with_fixed_args() but
does not release the obtained OF nodes. Thus add a of_node_put() call.

This bug was found by an experimental verification tool that I am
developing.

Fixes: 1be5336bc7ba ("dmaengine: edma: New device tree binding")
Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
---
Changes in v2:
- Get rid of the .node field in struct edma_tc and put the node in
  .probe().
---
 drivers/dma/ti/edma.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

Comments

Dan Carpenter Dec. 18, 2024, 9:09 a.m. UTC | #1
On Wed, Dec 18, 2024 at 10:15:20AM +0900, Joe Hattori wrote:
>  drivers/dma/ti/edma.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
> index 343e986e66e7..4ece125b2ae7 100644
> --- a/drivers/dma/ti/edma.c
> +++ b/drivers/dma/ti/edma.c
> @@ -208,7 +208,6 @@ struct edma_desc {
>  struct edma_cc;
>  
>  struct edma_tc {
> -	struct device_node		*node;
>  	u16				id;
>  };
>  
> @@ -2460,19 +2459,19 @@ static int edma_probe(struct platform_device *pdev)
>  			goto err_reg1;
>  		}
>  
> -		for (i = 0;; i++) {
> +		for (i = 0; i < ecc->num_tc; i++) {
>  			ret = of_parse_phandle_with_fixed_args(node, "ti,tptcs",
>  							       1, i, &tc_args);
> -			if (ret || i == ecc->num_tc)

I feel bad for not saying this earlier, but probably this
"i < ecc->num_tc" change should be done as patch 1/2?  It's sort of
related because if we didn't do this then we'd have to do this we'd
have to re-write it to for the i == ecc->num_tc to add another
of_node_put(tc_args.np).  But really it needs to be reviewed
separately.  It's such a weird thing, that I have to think that it
was done deliberately for some reason although I can't figure out why.

The rest of the patch is nice.  So much simpler than v1.

regards,
dan carpenter
Joe Hattori Dec. 19, 2024, 2:07 a.m. UTC | #2
Thank you for your review.

On 12/18/24 18:09, Dan Carpenter wrote:
> On Wed, Dec 18, 2024 at 10:15:20AM +0900, Joe Hattori wrote:
>>   drivers/dma/ti/edma.c | 7 +++----
>>   1 file changed, 3 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
>> index 343e986e66e7..4ece125b2ae7 100644
>> --- a/drivers/dma/ti/edma.c
>> +++ b/drivers/dma/ti/edma.c
>> @@ -208,7 +208,6 @@ struct edma_desc {
>>   struct edma_cc;
>>   
>>   struct edma_tc {
>> -	struct device_node		*node;
>>   	u16				id;
>>   };
>>   
>> @@ -2460,19 +2459,19 @@ static int edma_probe(struct platform_device *pdev)
>>   			goto err_reg1;
>>   		}
>>   
>> -		for (i = 0;; i++) {
>> +		for (i = 0; i < ecc->num_tc; i++) {
>>   			ret = of_parse_phandle_with_fixed_args(node, "ti,tptcs",
>>   							       1, i, &tc_args);
>> -			if (ret || i == ecc->num_tc)
> 
> I feel bad for not saying this earlier, but probably this
> "i < ecc->num_tc" change should be done as patch 1/2?  It's sort of
> related because if we didn't do this then we'd have to do this we'd
> have to re-write it to for the i == ecc->num_tc to add another
> of_node_put(tc_args.np).  But really it needs to be reviewed
> separately.  It's such a weird thing, that I have to think that it
> was done deliberately for some reason although I can't figure out why.

Totally. Separated the loop condition change as 1/2 and the rest as 2/2 
in the v3 patch.

> 
> The rest of the patch is nice.  So much simpler than v1.

Thanks :)

> 
> regards,
> dan carpenter
> 

Best,
Joe
diff mbox series

Patch

diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
index 343e986e66e7..4ece125b2ae7 100644
--- a/drivers/dma/ti/edma.c
+++ b/drivers/dma/ti/edma.c
@@ -208,7 +208,6 @@  struct edma_desc {
 struct edma_cc;
 
 struct edma_tc {
-	struct device_node		*node;
 	u16				id;
 };
 
@@ -2460,19 +2459,19 @@  static int edma_probe(struct platform_device *pdev)
 			goto err_reg1;
 		}
 
-		for (i = 0;; i++) {
+		for (i = 0; i < ecc->num_tc; i++) {
 			ret = of_parse_phandle_with_fixed_args(node, "ti,tptcs",
 							       1, i, &tc_args);
-			if (ret || i == ecc->num_tc)
+			if (ret)
 				break;
 
-			ecc->tc_list[i].node = tc_args.np;
 			ecc->tc_list[i].id = i;
 			queue_priority_mapping[i][1] = tc_args.args[0];
 			if (queue_priority_mapping[i][1] > lowest_priority) {
 				lowest_priority = queue_priority_mapping[i][1];
 				info->default_queue = i;
 			}
+			of_node_put(tc_args.np);
 		}
 
 		/* See if we have optional dma-channel-mask array */