[PATCH next] drm/amdgpu: Fix error codes if copy_to_user() fails

[PATCH next] drm/amdgpu: Fix error codes if copy_to_user() fails

[Dan Carpenter]

The copy_to_user() function returns the number of bytes that it wasn't
able to copy, but we should return -EFAULT to the user.

Fixes: 4d82724f7f2b ("drm/amdgpu: Add mapping info option for GEM_OP ioctl")
Fixes: f9db1fc52ceb ("drm/amdgpu: Add ioctl to get all gem handles for a process")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index 63eb75a579ce..2b58bc805374 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -1067,7 +1067,8 @@ int amdgpu_gem_op_ioctl(struct drm_device *dev, void *data,
 		drm_exec_fini(&exec);
 
 		if (num_mappings > 0 && num_mappings <= args->num_entries)
-			r = copy_to_user(u64_to_user_ptr(args->value), vm_entries, num_mappings * sizeof(*vm_entries));
+			if (copy_to_user(u64_to_user_ptr(args->value), vm_entries, num_mappings * sizeof(*vm_entries)))
+				r = -EFAULT;
 
 		args->num_entries = num_mappings;
 
@@ -1159,7 +1160,8 @@ int amdgpu_gem_list_handles_ioctl(struct drm_device *dev, void *data,
 	args->num_entries = bo_index;
 
 	if (!ret)
-		ret = copy_to_user(u64_to_user_ptr(args->entries), bo_entries, num_bos * sizeof(*bo_entries));
+		if (copy_to_user(u64_to_user_ptr(args->entries), bo_entries, num_bos * sizeof(*bo_entries)))
+			ret = -EFAULT;
 
 	kvfree(bo_entries);
 
-- 
2.47.2

Re: [PATCH next] drm/amdgpu: Fix error codes if copy_to_user() fails

[Alex Deucher]

Applied.  Thanks!

On Fri, Sep 5, 2025 at 8:59 AM Francis, David <David.Francis@amd.com> wrote:
>
> [AMD Official Use Only - AMD Internal Distribution Only]
>
> Whoops. Yep, story checks out.
>
> This is
> Reviewed-By: David Francis <David.Francis@amd.com>
> ________________________________
> From: Dan Carpenter <dan.carpenter@linaro.org>
> Sent: Thursday, September 4, 2025 2:58 PM
> To: Francis, David <David.Francis@amd.com>
> Cc: Deucher, Alexander <Alexander.Deucher@amd.com>; Koenig, Christian <Christian.Koenig@amd.com>; David Airlie <airlied@gmail.com>; Simona Vetter <simona@ffwll.ch>; Arvind Yadav <Arvind.Yadav@amd.com>; Sharma, Shashank <Shashank.Sharma@amd.com>; Thomas Zimmermann <tzimmermann@suse.de>; amd-gfx@lists.freedesktop.org <amd-gfx@lists.freedesktop.org>; dri-devel@lists.freedesktop.org <dri-devel@lists.freedesktop.org>; linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>; kernel-janitors@vger.kernel.org <kernel-janitors@vger.kernel.org>
> Subject: [PATCH next] drm/amdgpu: Fix error codes if copy_to_user() fails
>
> The copy_to_user() function returns the number of bytes that it wasn't
> able to copy, but we should return -EFAULT to the user.
>
> Fixes: 4d82724f7f2b ("drm/amdgpu: Add mapping info option for GEM_OP ioctl")
> Fixes: f9db1fc52ceb ("drm/amdgpu: Add ioctl to get all gem handles for a process")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> index 63eb75a579ce..2b58bc805374 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> @@ -1067,7 +1067,8 @@ int amdgpu_gem_op_ioctl(struct drm_device *dev, void *data,
>                  drm_exec_fini(&exec);
>
>                  if (num_mappings > 0 && num_mappings <= args->num_entries)
> -                       r = copy_to_user(u64_to_user_ptr(args->value), vm_entries, num_mappings * sizeof(*vm_entries));
> +                       if (copy_to_user(u64_to_user_ptr(args->value), vm_entries, num_mappings * sizeof(*vm_entries)))
> +                               r = -EFAULT;
>
>                  args->num_entries = num_mappings;
>
> @@ -1159,7 +1160,8 @@ int amdgpu_gem_list_handles_ioctl(struct drm_device *dev, void *data,
>          args->num_entries = bo_index;
>
>          if (!ret)
> -               ret = copy_to_user(u64_to_user_ptr(args->entries), bo_entries, num_bos * sizeof(*bo_entries));
> +               if (copy_to_user(u64_to_user_ptr(args->entries), bo_entries, num_bos * sizeof(*bo_entries)))
> +                       ret = -EFAULT;
>
>          kvfree(bo_entries);
>
> --
> 2.47.2
>