Re: [PATCH] crypto: ccp: Use memdup_user() rather than duplicating its implementation

[Gary R Hook]

On 03/05/2018 07:10 AM, SF Markus Elfring wrote:

From: Markus Elfring <elfr...@users.sourceforge.net>
Date: Mon, 5 Mar 2018 13:50:13 +0100

Reuse existing functionality from memdup_user() instead of keeping
duplicate source code.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfr...@users.sourceforge.net>

Acked-by: Gary R Hook <gary.h...@amd.com>

---
  drivers/crypto/ccp/psp-dev.c | 15 +--------------
  1 file changed, 1 insertion(+), 14 deletions(-)

diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
index fcfa5b1eae61..8255258cd040 100644
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -367,8 +367,6 @@ static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp)

void *psp_copy_user_blob(u64 __user uaddr, u32 len)

  {
-       void *data;
-
        if (!uaddr || !len)
                return ERR_PTR(-EINVAL);

@@ -376,18 +374,7 @@ void *psp_copy_user_blob(u64 __user uaddr, u32 len)

        if (len > SEV_FW_BLOB_MAX_SIZE)
                return ERR_PTR(-EINVAL);

- data = kmalloc(len, GFP_KERNEL);

-       if (!data)
-               return ERR_PTR(-ENOMEM);
-
-       if (copy_from_user(data, (void __user *)(uintptr_t)uaddr, len))
-               goto e_free;
-
-       return data;
-
-e_free:
-       kfree(data);
-       return ERR_PTR(-EFAULT);
+       return memdup_user((void __user *)(uintptr_t)uaddr, len);
  }
  EXPORT_SYMBOL_GPL(psp_copy_user_blob);