Re: [PATCH 21/46] selinux: Two function calls less in range_read() after error detection

From: Casey Schaufler
Date: Tue Jan 17 2017 - 11:35:36 EST


On 1/15/2017 7:21 AM, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> Date: Sat, 14 Jan 2017 20:20:15 +0100
>
> Adjust a jump target to avoid two calls of the function "kfree" at the end
> after a memory allocation failed for the local variable "rt".
>
> Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> ---
> security/selinux/ss/policydb.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
> index 4cd96ce51322..0d2f64558c0a 100644
> --- a/security/selinux/ss/policydb.c
> +++ b/security/selinux/ss/policydb.c
> @@ -1857,7 +1857,7 @@ static int range_read(struct policydb *p, void *fp)
> rt = kzalloc(sizeof(*rt), GFP_KERNEL);
> if (!rt) {
> rc = -ENOMEM;
> - goto out;
> + goto exit;

Why not "return rc;"?
goto to a return is wrong.

> }
>
> rc = next_entry(buf, fp, (sizeof(u32) * 2));
> @@ -1909,6 +1909,7 @@ static int range_read(struct policydb *p, void *fp)
> out:
> kfree(rt);
> kfree(r);
> +exit:
> return rc;
> }
>