2021-08-08 07:13:26

by Kangmin Park

Subject: [PATCH v3 net] ipv4: fix error path in fou_create()

sock is always NULL when udp_sock_create() is failed and fou is
always NULL when kzalloc() is failed in error label.

So, add error_sock and error_alloc label and fix the error path
in those cases.

Signed-off-by: Kangmin Park <[email protected]>
---
v3:
- change commit message
- fix error path
---
net/ipv4/fou.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index e5f69b0bf3df..f1d99e776bb8 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c
@@ -572,13 +572,13 @@ static int fou_create(struct net *net, struct fou_cfg *cfg,
/* Open UDP socket */
err = udp_sock_create(net, &cfg->udp_config, &sock);
if (err < 0)
- goto error;
+ goto error_sock;

/* Allocate FOU port structure */
fou = kzalloc(sizeof(*fou), GFP_KERNEL);
if (!fou) {
err = -ENOMEM;
- goto error;
+ goto error_alloc;
}

sk = sock->sk;
@@ -627,9 +627,10 @@ static int fou_create(struct net *net, struct fou_cfg *cfg,

error:
kfree(fou);
+error_alloc:
if (sock)
udp_tunnel_sock_release(sock);
-
+error_sock:
return err;
}

--
2.26.2

2021-08-08 20:07:05

by David Ahern

Subject: Re: [PATCH v3 net] ipv4: fix error path in fou_create()

On 8/8/21 1:05 AM, Kangmin Park wrote:
> sock is always NULL when udp_sock_create() is failed and fou is
> always NULL when kzalloc() is failed in error label.
>
> So, add error_sock and error_alloc label and fix the error path
> in those cases.
>
> Signed-off-by: Kangmin Park <[email protected]>
> ---
> v3:
> - change commit message
> - fix error path
> ---
> net/ipv4/fou.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
> index e5f69b0bf3df..f1d99e776bb8 100644
> --- a/net/ipv4/fou.c
> +++ b/net/ipv4/fou.c
> @@ -572,13 +572,13 @@ static int fou_create(struct net *net, struct fou_cfg *cfg,
> /* Open UDP socket */
> err = udp_sock_create(net, &cfg->udp_config, &sock);
> if (err < 0)
> - goto error;
> + goto error_sock;
>
> /* Allocate FOU port structure */
> fou = kzalloc(sizeof(*fou), GFP_KERNEL);
> if (!fou) {
> err = -ENOMEM;
> - goto error;
> + goto error_alloc;
> }
>
> sk = sock->sk;
> @@ -627,9 +627,10 @@ static int fou_create(struct net *net, struct fou_cfg *cfg,
>
> error:
> kfree(fou);
> +error_alloc:
> if (sock)
> udp_tunnel_sock_release(sock);
> -
> +error_sock:
> return err;
> }
>
>

since sock and fou are initialized to NULL, kfree(NULL) is allowed and
there is an 'if (sock)' check before the release, no fix is really needed.