[PATCH] VMCI: Use memdup_user() rather than duplicating its implementation

From: SF Markus Elfring
Date: Fri Aug 19 2016 - 15:21:18 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Fri, 19 Aug 2016 21:12:41 +0200

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>
---
drivers/misc/vmw_vmci/vmci_host.c | 19 ++++---------------
1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/drivers/misc/vmw_vmci/vmci_host.c b/drivers/misc/vmw_vmci/vmci_host.c
index 9ec262a..0a20475 100644
--- a/drivers/misc/vmw_vmci/vmci_host.c
+++ b/drivers/misc/vmw_vmci/vmci_host.c
@@ -759,27 +759,16 @@ static int vmci_host_do_ctx_set_cpt_state(struct vmci_host_dev *vmci_host_dev,
if (copy_from_user(&set_info, uptr, sizeof(set_info)))
return -EFAULT;

- cpt_buf = kmalloc(set_info.buf_size, GFP_KERNEL);
- if (!cpt_buf) {
- vmci_ioctl_err(
- "cannot allocate memory to set cpt state (type=%d)\n",
- set_info.cpt_type);
- return -ENOMEM;
- }
-
- if (copy_from_user(cpt_buf, (void __user *)(uintptr_t)set_info.cpt_buf,
- set_info.buf_size)) {
- retval = -EFAULT;
- goto out;
- }
+ cpt_buf = memdup_user((void __user *)(uintptr_t)set_info.cpt_buf,
+ set_info.buf_size);
+ if (IS_ERR(cpt_buf))
+ return PTR_ERR(cpt_buf);

cid = vmci_ctx_get_id(vmci_host_dev->context);
set_info.result = vmci_ctx_set_chkpt_state(cid, set_info.cpt_type,
set_info.buf_size, cpt_buf);

retval = copy_to_user(uptr, &set_info, sizeof(set_info)) ? -EFAULT : 0;
-
-out:
kfree(cpt_buf);
return retval;
}
--
2.9.3