amdgpu_discovery_sysfs_ips() allocates ip_hw_instance with
kzalloc_flex() and initializes its embedded kobject before calling
kobject_add().

If kobject_add() fails, the return value is ignored and execution
continues without dropping the initial kobject reference. The failed
kobject is not retained in the kset list, so the normal sysfs teardown
path cannot find it. As a result, ip_hw_instance_release() is never
called and the ip_hw_instance allocation is leaked.

Call kobject_put() when kobject_add() fails so the initial reference is
dropped and ip_hw_instance_release() can free the allocation. Keep the
existing best-effort sysfs behavior by continuing with the remaining IP
entries after the failed registration.

The issue was identified by a static analysis tool I developed and
confirmed by manual review.

Fixes: a6c40b178092 ("drm/amdgpu: Show IP discovery in sysfs")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
index a404d8aa13ee..4b1ad1c0a10b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
@@ -1314,6 +1314,8 @@ static int amdgpu_discovery_sysfs_ips(struct amdgpu_device *adev,
 			ip_hw_instance->kobj.kset = &ip_hw_id->hw_id_kset;
 			res = kobject_add(&ip_hw_instance->kobj, NULL,
 					  "%d", ip_hw_instance->num_instance);
+			if (res)
+				kobject_put(&ip_hw_instance->kobj);
 next_ip:
 			if (reg_base_64)
 				ip_offset += struct_size(ip, base_address_64,
-- 
2.43.0

On 19-Sep-26 10:25 PM, Guangshuo Li wrote:
> amdgpu_discovery_sysfs_ips() allocates ip_hw_instance with
> kzalloc_flex() and initializes its embedded kobject before calling
> kobject_add().
> 
> If kobject_add() fails, the return value is ignored and execution
> continues without dropping the initial kobject reference. The failed
> kobject is not retained in the kset list, so the normal sysfs teardown
> path cannot find it. As a result, ip_hw_instance_release() is never
> called and the ip_hw_instance allocation is leaked.
> 
> Call kobject_put() when kobject_add() fails so the initial reference is
> dropped and ip_hw_instance_release() can free the allocation. Keep the
> existing best-effort sysfs behavior by continuing with the remaining IP
> entries after the failed registration.
> 
> The issue was identified by a static analysis tool I developed and
> confirmed by manual review.
> 
> Fixes: a6c40b178092 ("drm/amdgpu: Show IP discovery in sysfs")
> Cc: stable@vger.kernel.org
> Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> index a404d8aa13ee..4b1ad1c0a10b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> @@ -1314,6 +1314,8 @@ static int amdgpu_discovery_sysfs_ips(struct amdgpu_device *adev,
>   			ip_hw_instance->kobj.kset = &ip_hw_id->hw_id_kset;
>   			res = kobject_add(&ip_hw_instance->kobj, NULL,
>   					  "%d", ip_hw_instance->num_instance);
> +			if (res)
> +				kobject_put(&ip_hw_instance->kobj);

Adding a message that this instance got skipped also will help.

Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>

Thanks,
Lijo

>   next_ip:
>   			if (reg_base_64)
>   				ip_offset += struct_size(ip, base_address_64,

Applied.  Thanks!

On Mon, Sep 21, 2026 at 1:16 AM Lazar, Lijo <lijo.lazar@amd.com> wrote:
>
>
>
> On 19-Sep-26 10:25 PM, Guangshuo Li wrote:
> > amdgpu_discovery_sysfs_ips() allocates ip_hw_instance with
> > kzalloc_flex() and initializes its embedded kobject before calling
> > kobject_add().
> >
> > If kobject_add() fails, the return value is ignored and execution
> > continues without dropping the initial kobject reference. The failed
> > kobject is not retained in the kset list, so the normal sysfs teardown
> > path cannot find it. As a result, ip_hw_instance_release() is never
> > called and the ip_hw_instance allocation is leaked.
> >
> > Call kobject_put() when kobject_add() fails so the initial reference is
> > dropped and ip_hw_instance_release() can free the allocation. Keep the
> > existing best-effort sysfs behavior by continuing with the remaining IP
> > entries after the failed registration.
> >
> > The issue was identified by a static analysis tool I developed and
> > confirmed by manual review.
> >
> > Fixes: a6c40b178092 ("drm/amdgpu: Show IP discovery in sysfs")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> > index a404d8aa13ee..4b1ad1c0a10b 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> > @@ -1314,6 +1314,8 @@ static int amdgpu_discovery_sysfs_ips(struct amdgpu_device *adev,
> >                       ip_hw_instance->kobj.kset = &ip_hw_id->hw_id_kset;
> >                       res = kobject_add(&ip_hw_instance->kobj, NULL,
> >                                         "%d", ip_hw_instance->num_instance);
> > +                     if (res)
> > +                             kobject_put(&ip_hw_instance->kobj);
>
> Adding a message that this instance got skipped also will help.
>
> Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
>
> Thanks,
> Lijo
>
> >   next_ip:
> >                       if (reg_base_64)
> >                               ip_offset += struct_size(ip, base_address_64,
>