[2/3] staging: wilc1000: One function call less in mac_ioctl() after error detection

Commit Message

SF Markus Elfring July 24, 2016, 8:22 p.m. UTC

From: Markus Elfring <[e-mail]>
Date: Sun, 24 Jul 2016 21:15:23 +0200

The kfree() function was called in two cases by the mac_ioctl() function
during error handling even if the passed variable did not contain a pointer
for a valid data item.

Improve this implementation detail by the introduction of another
jump label.

Signed-off-by: Markus Elfring <[e-mail]>
---
 drivers/staging/wilc1000/linux_wlan.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

Comments

Julian Calaby July 28, 2016, 12:02 p.m. UTC | #1

Hi Marcus,

On Mon, Jul 25, 2016 at 6:22 AM, SF Markus Elfring
<[e-mail]> wrote:
> From: Markus Elfring <[e-mail]>
> Date: Sun, 24 Jul 2016 21:15:23 +0200
>
> The kfree() function was called in two cases by the mac_ioctl() function
> during error handling even if the passed variable did not contain a pointer
> for a valid data item.
>
> Improve this implementation detail by the introduction of another
> jump label.
>
> Signed-off-by: Markus Elfring <[e-mail]>

This is pointless micro-optimisation: kfree(NULL) is perfectly valid
and buff is either malloc'd memory or NULL when it's called.

Thanks,

Patch

diff --git a/drivers/staging/wilc1000/linux_wlan.c b/drivers/staging/wilc1000/linux_wlan.c
index cdef645..7b1ebcc 100644
--- a/drivers/staging/wilc1000/linux_wlan.c
+++ b/drivers/staging/wilc1000/linux_wlan.c
@@ -1130,7 +1130,7 @@  static int mac_ioctl(struct net_device *ndev, struct ifreq *req, int cmd)
 				if (copy_to_user(wrq->u.data.pointer, buff, size)) {
 					netdev_err(ndev, "failed to copy\n");
 					ret = -EFAULT;
-					goto done;
+					goto free_buffer;
 				}
 			}
 		}
@@ -1144,11 +1144,9 @@  static int mac_ioctl(struct net_device *ndev, struct ifreq *req, int cmd)
 		goto done;
 	}
 	}
-
-done:
-
+free_buffer:
 	kfree(buff);
-
+done:
 	return ret;
 }