[PATCH 4/4] drm/amdgpu: Use memdup_user in ta_if_load_debugfs_write

[Tvrtko Ursulin]

Replace kzalloc() + copy_from_user() with memdup_user().

This shrinks the source code and improves separation between the kernel
and userspace slabs.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at igalia.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_psp_ta.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp_ta.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp_ta.c
index 38face981c3e..e0a604b6c633 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp_ta.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp_ta.c
@@ -141,7 +141,7 @@ static const struct file_operations ta_invoke_debugfs_fops = {
  *    - TA ID (4bytes)
  */
 
-static ssize_t ta_if_load_debugfs_write(struct file *fp, const char *buf, size_t len, loff_t *off)
+static ssize_t ta_if_load_debugfs_write(struct file *fp, const char __user *buf, size_t len, loff_t *off)
 {
 	uint32_t ta_type    = 0;
 	uint32_t ta_bin_len = 0;
@@ -171,13 +171,9 @@ static ssize_t ta_if_load_debugfs_write(struct file *fp, const char *buf, size_t
 
 	copy_pos += sizeof(uint32_t);
 
-	ta_bin = kzalloc(ta_bin_len, GFP_KERNEL);
-	if (!ta_bin)
-		return -ENOMEM;
-	if (copy_from_user((void *)ta_bin, &buf[copy_pos], ta_bin_len)) {
-		ret = -EFAULT;
-		goto err_free_bin;
-	}
+	ta_bin = memdup_user(&buf[copy_pos], ta_bin_len);
+	if (IS_ERR(ta_bin))
+		return PTR_ERR(ta_bin);
 
 	/* Set TA context and functions */
 	set_ta_context_funcs(psp, ta_type, &context);
@@ -231,7 +227,7 @@ static ssize_t ta_if_load_debugfs_write(struct file *fp, const char *buf, size_t
 		goto err_free_ta_shared_buf;
 	}
 
-	if (copy_to_user((char *)buf, (void *)&context->session_id, sizeof(uint32_t)))
+	if (copy_to_user((char __user *)buf, (void *)&context->session_id, sizeof(uint32_t)))
 		ret = -EFAULT;
 
 err_free_ta_shared_buf:
-- 
2.48.0