diff mbox series

rpmsg: virtio: fix possible double free in rpmsg_probe()

Message ID 20220418093144.40859-1-hbh25y@gmail.com (mailing list archive)
State Changes Requested
Headers show
Series rpmsg: virtio: fix possible double free in rpmsg_probe() | expand

Commit Message

Hangyu Hua April 18, 2022, 9:31 a.m. UTC
vch will be free in virtio_rpmsg_release_device() when
rpmsg_ns_register_device() fails. There is no need to call kfree() again.

Fix this by changing error path from free_vch to free_ctrldev.

Fixes: c486682ae1e2 ("rpmsg: virtio: Register the rpmsg_char device")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
---
 drivers/rpmsg/virtio_rpmsg_bus.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

Comments

Arnaud POULIQUEN April 22, 2022, 3:29 p.m. UTC | #1
On 4/18/22 11:31, Hangyu Hua wrote:
> vch will be free in virtio_rpmsg_release_device() when
> rpmsg_ns_register_device() fails. There is no need to call kfree() again.
> 
> Fix this by changing error path from free_vch to free_ctrldev.
> 
> Fixes: c486682ae1e2 ("rpmsg: virtio: Register the rpmsg_char device")
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>

Tested-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>

Thanks,
Arnaud

> ---
>  drivers/rpmsg/virtio_rpmsg_bus.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
> index 3ede25b1f2e4..603233f0686e 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -973,7 +973,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  
>  		err = rpmsg_ns_register_device(rpdev_ns);
>  		if (err)
> -			goto free_vch;
> +			goto free_ctrldev;
>  	}
>  
>  	/*
> @@ -997,8 +997,6 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  
>  	return 0;
>  
> -free_vch:
> -	kfree(vch);
>  free_ctrldev:
>  	rpmsg_virtio_del_ctrl_dev(rpdev_ctrl);
>  free_coherent:
Mathieu Poirier April 25, 2022, 4:55 p.m. UTC | #2
On Mon, Apr 18, 2022 at 05:31:44PM +0800, Hangyu Hua wrote:
> vch will be free in virtio_rpmsg_release_device() when
> rpmsg_ns_register_device() fails. There is no need to call kfree() again.
> 
> Fix this by changing error path from free_vch to free_ctrldev.
> 
> Fixes: c486682ae1e2 ("rpmsg: virtio: Register the rpmsg_char device")
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
> ---
>  drivers/rpmsg/virtio_rpmsg_bus.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
> index 3ede25b1f2e4..603233f0686e 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -973,7 +973,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  
>  		err = rpmsg_ns_register_device(rpdev_ns);
>  		if (err)
> -			goto free_vch;

Please add a comment that highlights where 'vch' will be free'd to avoid
receiving patches that will introduce another kfree().  Same for your other
patch.

In the next revision please use a cover letter and add Arnaud's patches to it.

Thanks,
Mathieu

> +			goto free_ctrldev;
>  	}
>  
>  	/*
> @@ -997,8 +997,6 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  
>  	return 0;
>  
> -free_vch:
> -	kfree(vch);
>  free_ctrldev:
>  	rpmsg_virtio_del_ctrl_dev(rpdev_ctrl);
>  free_coherent:
> -- 
> 2.25.1
>
Hangyu Hua April 26, 2022, 1:40 a.m. UTC | #3
On 2022/4/26 00:55, Mathieu Poirier wrote:
> On Mon, Apr 18, 2022 at 05:31:44PM +0800, Hangyu Hua wrote:
>> vch will be free in virtio_rpmsg_release_device() when
>> rpmsg_ns_register_device() fails. There is no need to call kfree() again.
>>
>> Fix this by changing error path from free_vch to free_ctrldev.
>>
>> Fixes: c486682ae1e2 ("rpmsg: virtio: Register the rpmsg_char device")
>> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
>> ---
>>   drivers/rpmsg/virtio_rpmsg_bus.c | 4 +---
>>   1 file changed, 1 insertion(+), 3 deletions(-)
>>
>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
>> index 3ede25b1f2e4..603233f0686e 100644
>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
>> @@ -973,7 +973,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
>>   
>>   		err = rpmsg_ns_register_device(rpdev_ns);
>>   		if (err)
>> -			goto free_vch;
> 
> Please add a comment that highlights where 'vch' will be free'd to avoid
> receiving patches that will introduce another kfree().  Same for your other
> patch.
> 
> In the next revision please use a cover letter and add Arnaud's patches to it.
> 
> Thanks,
> Mathieu
> 

Thanks! I will send a v2 later.

>> +			goto free_ctrldev;
>>   	}
>>   
>>   	/*
>> @@ -997,8 +997,6 @@ static int rpmsg_probe(struct virtio_device *vdev)
>>   
>>   	return 0;
>>   
>> -free_vch:
>> -	kfree(vch);
>>   free_ctrldev:
>>   	rpmsg_virtio_del_ctrl_dev(rpdev_ctrl);
>>   free_coherent:
>> -- 
>> 2.25.1
>>
diff mbox series

Patch

diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 3ede25b1f2e4..603233f0686e 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -973,7 +973,7 @@  static int rpmsg_probe(struct virtio_device *vdev)
 
 		err = rpmsg_ns_register_device(rpdev_ns);
 		if (err)
-			goto free_vch;
+			goto free_ctrldev;
 	}
 
 	/*
@@ -997,8 +997,6 @@  static int rpmsg_probe(struct virtio_device *vdev)
 
 	return 0;
 
-free_vch:
-	kfree(vch);
 free_ctrldev:
 	rpmsg_virtio_del_ctrl_dev(rpdev_ctrl);
 free_coherent: