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

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: 553f973a0d7b ("drm/amd/amdgpu: Update debugfs for XCC support (v3)")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index c657bed..56e89e7 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -478,15 +478,16 @@ done:
 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(&rd->lock);
 
        switch (cmd) {
        case AMDGPU_DEBUGFS_GPRWAVE_IOC_SET_STATE:
-               r = copy_from_user(&rd->id, (struct amdgpu_debugfs_gprwave_iocdata *)data, sizeof rd->id);
-               if (r)
-                       return r ? -EINVAL : 0;
+               if (copy_from_user(&rd->id,
+                                  (struct amdgpu_debugfs_gprwave_iocdata *)data,
+                                  sizeof(rd->id)))
+                       r = -EFAULT;
                goto done;
        default:
                r = -EINVAL;