Re: [PATCH] drm/amd/amdgpu: Fix up locking etc in amdgpu_debugfs_gprwave_ioctl()

[Alex Deucher]

Applied.  Thanks!

Alex

On Thu, May 25, 2023 at 4:05 AM Dan Carpenter  wrote:
>
> There are two bugs here.
> 1) Drop the lock if copy_from_user() fails.
> 2) If the copy fails then the correct error code is -EFAULT instead of
>-EINVAL.
>
> I also broke up the long line and changed "sizeof rd->id" to
> "sizeof(rd->id)".
>
> Fixes: 164fb2940933 ("drm/amd/amdgpu: Update debugfs for XCC support (v3)")
> Signed-off-by: Dan Carpenter 
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 9 +
>  1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c 
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> index c657bed350ac..56e89e76ff17 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
> @@ -478,15 +478,16 @@ static ssize_t amdgpu_debugfs_gprwave_read(struct file 
> *f, char __user *buf, siz
>  static long amdgpu_debugfs_gprwave_ioctl(struct file *f, unsigned int cmd, 
> unsigned long data)
>  {
> struct amdgpu_debugfs_gprwave_data *rd = f->private_data;
> -   int r;
> +   int r = 0;
>
> mutex_lock(>lock);
>
> switch (cmd) {
> case AMDGPU_DEBUGFS_GPRWAVE_IOC_SET_STATE:
> -   r = copy_from_user(>id, (struct 
> amdgpu_debugfs_gprwave_iocdata *)data, sizeof rd->id);
> -   if (r)
> -   return r ? -EINVAL : 0;
> +   if (copy_from_user(>id,
> +  (struct amdgpu_debugfs_gprwave_iocdata 
> *)data,
> +  sizeof(rd->id)))
> +   r = -EFAULT;
> goto done;
> default:
> r = -EINVAL;
> --
> 2.39.2
>

[PATCH] drm/amd/amdgpu: Fix up locking etc in amdgpu_debugfs_gprwave_ioctl()

[Dan Carpenter]

There are two bugs here.
1) Drop the lock if copy_from_user() fails.
2) If the copy fails then the correct error code is -EFAULT instead of
   -EINVAL.

I also broke up the long line and changed "sizeof rd->id" to
"sizeof(rd->id)".

Fixes: 164fb2940933 ("drm/amd/amdgpu: Update debugfs for XCC support (v3)")
Signed-off-by: Dan Carpenter 
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 9 +
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index c657bed350ac..56e89e76ff17 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -478,15 +478,16 @@ static ssize_t amdgpu_debugfs_gprwave_read(struct file 
*f, char __user *buf, siz
 static long amdgpu_debugfs_gprwave_ioctl(struct file *f, unsigned int cmd, 
unsigned long data)
 {
struct amdgpu_debugfs_gprwave_data *rd = f->private_data;
-   int r;
+   int r = 0;
 
mutex_lock(>lock);
 
switch (cmd) {
case AMDGPU_DEBUGFS_GPRWAVE_IOC_SET_STATE:
-   r = copy_from_user(>id, (struct 
amdgpu_debugfs_gprwave_iocdata *)data, sizeof rd->id);
-   if (r)
-   return r ? -EINVAL : 0;
+   if (copy_from_user(>id,
+  (struct amdgpu_debugfs_gprwave_iocdata 
*)data,
+  sizeof(rd->id)))
+   r = -EFAULT;
goto done;
default:
r = -EINVAL;
-- 
2.39.2