2021-06-30 09:16:54

by Yajun Deng

[permalink] [raw]
Subject: [PATCH] net: x25: Optimize the code in {compat_}x25_subscr_ioctl()

Combine the redundant return values, make it more concise.

Signed-off-by: Yajun Deng <[email protected]>
---
net/x25/af_x25.c | 19 ++++++++-----------
net/x25/x25_link.c | 21 ++++++++++-----------
2 files changed, 18 insertions(+), 22 deletions(-)

diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index 3583354a7d7f..53c40fc7c1fd 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -1625,21 +1625,19 @@ static int compat_x25_subscr_ioctl(unsigned int cmd,
struct net_device *dev;
int rc = -EINVAL;

- rc = -EFAULT;
- if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
+ if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32))) {
+ rc = -EFAULT;
goto out;
+ }

- rc = -EINVAL;
dev = x25_dev_get(x25_subscr.device);
- if (dev == NULL)
+ if (!dev)
goto out;

nb = x25_get_neigh(dev);
- if (nb == NULL)
+ if (!nb)
goto out_dev_put;

- dev_put(dev);
-
if (cmd == SIOCX25GSUBSCRIP) {
read_lock_bh(&x25_neigh_list_lock);
x25_subscr.extended = nb->extended;
@@ -1648,7 +1646,6 @@ static int compat_x25_subscr_ioctl(unsigned int cmd,
rc = copy_to_user(x25_subscr32, &x25_subscr,
sizeof(*x25_subscr32)) ? -EFAULT : 0;
} else {
- rc = -EINVAL;
if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
rc = 0;
write_lock_bh(&x25_neigh_list_lock);
@@ -1658,11 +1655,11 @@ static int compat_x25_subscr_ioctl(unsigned int cmd,
}
}
x25_neigh_put(nb);
-out:
- return rc;
+
out_dev_put:
dev_put(dev);
- goto out;
+out:
+ return rc;
}

static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
diff --git a/net/x25/x25_link.c b/net/x25/x25_link.c
index 5460b9146dd8..01a13ec88ce8 100644
--- a/net/x25/x25_link.c
+++ b/net/x25/x25_link.c
@@ -360,19 +360,19 @@ int x25_subscr_ioctl(unsigned int cmd, void __user *arg)
if (cmd != SIOCX25GSUBSCRIP && cmd != SIOCX25SSUBSCRIP)
goto out;

- rc = -EFAULT;
- if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr)))
+ if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr))) {
+ rc = -EFAULT;
goto out;
+ }

- rc = -EINVAL;
- if ((dev = x25_dev_get(x25_subscr.device)) == NULL)
+ dev = x25_dev_get(x25_subscr.device);
+ if (!dev)
goto out;

- if ((nb = x25_get_neigh(dev)) == NULL)
+ nb = x25_get_neigh(dev);
+ if (!nb)
goto out_dev_put;

- dev_put(dev);
-
if (cmd == SIOCX25GSUBSCRIP) {
read_lock_bh(&x25_neigh_list_lock);
x25_subscr.extended = nb->extended;
@@ -381,7 +381,6 @@ int x25_subscr_ioctl(unsigned int cmd, void __user *arg)
rc = copy_to_user(arg, &x25_subscr,
sizeof(x25_subscr)) ? -EFAULT : 0;
} else {
- rc = -EINVAL;
if (!(x25_subscr.extended && x25_subscr.extended != 1)) {
rc = 0;
write_lock_bh(&x25_neigh_list_lock);
@@ -391,11 +390,11 @@ int x25_subscr_ioctl(unsigned int cmd, void __user *arg)
}
}
x25_neigh_put(nb);
-out:
- return rc;
+
out_dev_put:
dev_put(dev);
- goto out;
+out:
+ return rc;
}


--
2.32.0


2021-07-01 05:59:09

by Martin Schiller

[permalink] [raw]
Subject: Re: [PATCH] net: x25: Optimize the code in {compat_}x25_subscr_ioctl()

On 2021-06-30 11:15, Yajun Deng wrote:
> Combine the redundant return values, make it more concise.
>
> Signed-off-by: Yajun Deng <[email protected]>
> ---
> net/x25/af_x25.c | 19 ++++++++-----------
> net/x25/x25_link.c | 21 ++++++++++-----------
> 2 files changed, 18 insertions(+), 22 deletions(-)
>
> diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
> index 3583354a7d7f..53c40fc7c1fd 100644
> --- a/net/x25/af_x25.c
> +++ b/net/x25/af_x25.c
> @@ -1625,21 +1625,19 @@ static int compat_x25_subscr_ioctl(unsigned int
> cmd,
> struct net_device *dev;
> int rc = -EINVAL;
>
> - rc = -EFAULT;
> - if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
> + if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32)))
> {
> + rc = -EFAULT;
> goto out;
> + }
>
> - rc = -EINVAL;
> dev = x25_dev_get(x25_subscr.device);
> - if (dev == NULL)
> + if (!dev)
> goto out;
>
> nb = x25_get_neigh(dev);
> - if (nb == NULL)
> + if (!nb)
> goto out_dev_put;
>
> - dev_put(dev);
> -
> if (cmd == SIOCX25GSUBSCRIP) {
> read_lock_bh(&x25_neigh_list_lock);
> x25_subscr.extended = nb->extended;
> @@ -1648,7 +1646,6 @@ static int compat_x25_subscr_ioctl(unsigned int
> cmd,
> rc = copy_to_user(x25_subscr32, &x25_subscr,
> sizeof(*x25_subscr32)) ? -EFAULT : 0;
> } else {
> - rc = -EINVAL;
> if (x25_subscr.extended == 0 || x25_subscr.extended == 1) {
> rc = 0;
> write_lock_bh(&x25_neigh_list_lock);
> @@ -1658,11 +1655,11 @@ static int compat_x25_subscr_ioctl(unsigned int
> cmd,
> }
> }
> x25_neigh_put(nb);
> -out:
> - return rc;
> +
> out_dev_put:
> dev_put(dev);
> - goto out;
> +out:
> + return rc;
> }
>
> static int compat_x25_ioctl(struct socket *sock, unsigned int cmd,
> diff --git a/net/x25/x25_link.c b/net/x25/x25_link.c
> index 5460b9146dd8..01a13ec88ce8 100644
> --- a/net/x25/x25_link.c
> +++ b/net/x25/x25_link.c
> @@ -360,19 +360,19 @@ int x25_subscr_ioctl(unsigned int cmd, void
> __user *arg)
> if (cmd != SIOCX25GSUBSCRIP && cmd != SIOCX25SSUBSCRIP)
> goto out;
>
> - rc = -EFAULT;
> - if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr)))
> + if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr))) {
> + rc = -EFAULT;
> goto out;
> + }
>
> - rc = -EINVAL;
> - if ((dev = x25_dev_get(x25_subscr.device)) == NULL)
> + dev = x25_dev_get(x25_subscr.device);
> + if (!dev)
> goto out;
>
> - if ((nb = x25_get_neigh(dev)) == NULL)
> + nb = x25_get_neigh(dev);
> + if (!nb)
> goto out_dev_put;
>
> - dev_put(dev);
> -
> if (cmd == SIOCX25GSUBSCRIP) {
> read_lock_bh(&x25_neigh_list_lock);
> x25_subscr.extended = nb->extended;
> @@ -381,7 +381,6 @@ int x25_subscr_ioctl(unsigned int cmd, void __user
> *arg)
> rc = copy_to_user(arg, &x25_subscr,
> sizeof(x25_subscr)) ? -EFAULT : 0;
> } else {
> - rc = -EINVAL;
> if (!(x25_subscr.extended && x25_subscr.extended != 1)) {
> rc = 0;
> write_lock_bh(&x25_neigh_list_lock);
> @@ -391,11 +390,11 @@ int x25_subscr_ioctl(unsigned int cmd, void
> __user *arg)
> }
> }
> x25_neigh_put(nb);
> -out:
> - return rc;
> +
> out_dev_put:
> dev_put(dev);
> - goto out;
> +out:
> + return rc;
> }

Looks good to me.

Acked-by: Martin Schiller <[email protected]>