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

From: Gary R Hook
Date: Mon Mar 05 2018 - 14:41:21 EST


On 03/05/2018 07:10 AM, SF Markus Elfring wrote:
From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
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 <elfring@xxxxxxxxxxxxxxxxxxxxx>

Acked-by: Gary R Hook <gary.hook@xxxxxxx>

---
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);