[PATCH] staging: greybus: Remove module from list before freeing in gb_audio_module_release

[PATCH] staging: greybus: Remove module from list before freeing in gb_audio_module_release

[Atharva Tiwari]

Previously,the module was freed without detaching it from the list which could lead to memory leak
this patch uses list_del to safely remove the module from the list

Signed-off-by: Atharva Tiwari <evepolonium@gmail.com>
---
 drivers/staging/greybus/audio_manager_module.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/greybus/audio_manager_module.c b/drivers/staging/greybus/audio_manager_module.c
index 4a4dfb42f50f..7e52c3f95692 100644
--- a/drivers/staging/greybus/audio_manager_module.c
+++ b/drivers/staging/greybus/audio_manager_module.c
@@ -69,7 +69,8 @@ static void gb_audio_module_release(struct kobject *kobj)
 	struct gb_audio_manager_module *module = to_gb_audio_module(kobj);
 
 	pr_info("Destroying audio module #%d\n", module->id);
-	/* TODO -> delete from list */
+	if (module->list.prev && module->list.next)
+		list_del(&module->list);
 	kfree(module);
 }
 
-- 
2.39.5

Re: [PATCH] staging: greybus: Remove module from list before freeing in gb_audio_module_release

[Greg Kroah-Hartman]

On Mon, Dec 23, 2024 at 08:41:12PM +0530, Atharva Tiwari wrote:
> Previously,the module was freed without detaching it from the list which could lead to memory leak
> this patch uses list_del to safely remove the module from the list
> 
> Signed-off-by: Atharva Tiwari <evepolonium@gmail.com>
> ---
>  drivers/staging/greybus/audio_manager_module.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/greybus/audio_manager_module.c b/drivers/staging/greybus/audio_manager_module.c
> index 4a4dfb42f50f..7e52c3f95692 100644
> --- a/drivers/staging/greybus/audio_manager_module.c
> +++ b/drivers/staging/greybus/audio_manager_module.c
> @@ -69,7 +69,8 @@ static void gb_audio_module_release(struct kobject *kobj)
>  	struct gb_audio_manager_module *module = to_gb_audio_module(kobj);
>  
>  	pr_info("Destroying audio module #%d\n", module->id);
> -	/* TODO -> delete from list */
> +	if (module->list.prev && module->list.next)

For lists, you really shouldn't poke around in the prev and next
pointers, right?

Have you tested this?  This feels like an odd change, is it a real
system that is using this code anymore?

thanks,

greg k-h

[PATCH] staging: greybus: Remove Module from list before freeing in gb_audio_module_release

[Atharva Tiwari]

Yes I have tested the patch with greybus drivers enabled on Debian 12.It works as expected, and i did not get any errors or warning during the compilation

Please let me know if further changes are required.

Best regards,
Atharva Tiwari

Re: [PATCH] staging: greybus: Remove Module from list before freeing in gb_audio_module_release

[Greg KH]

On Tue, Dec 24, 2024 at 10:49:17AM +0530, Atharva Tiwari wrote:
> Yes I have tested the patch with greybus drivers enabled on Debian 12.It works as expected, and i did not get any errors or warning during the compilation

I have no context here, sorry.

Remember, some of use get over 1000 emails a day to do something with,
always respond with proper email quoting and context of what is going
on.

Also, just bulding code does not mean it works :)

thanks,

greg k-h

Re: [PATCH] staging: greybus: Remove Module from list before freeing in gb_audio_module_release

[Dan Carpenter]

On Tue, Dec 24, 2024 at 10:49:17AM +0530, Atharva Tiwari wrote:
> Yes I have tested the patch with greybus drivers enabled on Debian 12.It works as expected, and i did not get any errors or warning during the compilation
> 
> Please let me know if further changes are required.
> 

You're trying to ensure that the list is initialized but instead of testing
for that, the correct way is to initialize it earlier in the process.

regards,
dan carpenter