Re: [PATCH 1/2] security: add cred argument to security_capable()

[Casey Schaufler <casey@schaufler-ca.com>]

On 2/9/2011 10:11 PM, Chris Wright wrote:
> Expand security_capable() to include cred, so that it can be usable in a
> wider range of call sites.

I'll bite. What to plan to use this for? I wouldn't see this getting
accepted on its own without a user. I don't see anything wrong with
the change other than that it is not used by anything.


> Cc: James Morris <jmorris@namei.org>
> Cc: Eric Paris <eparis@redhat.com>
> Cc: Serge Hallyn <serge.hallyn@canonical.com>
> Cc: linux-security-module@vger.kernel.org
> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
> ---
>
>  include/linux/security.h |    6 +++---
>  kernel/capability.c      |    2 +-
>  security/security.c      |    5 ++---
>  3 files changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index c642bb8..b2b7f97 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -1662,7 +1662,7 @@ int security_capset(struct cred *new, const struct cred *old,
>  		    const kernel_cap_t *effective,
>  		    const kernel_cap_t *inheritable,
>  		    const kernel_cap_t *permitted);
> -int security_capable(int cap);
> +int security_capable(const struct cred *cred, int cap);
>  int security_real_capable(struct task_struct *tsk, int cap);
>  int security_real_capable_noaudit(struct task_struct *tsk, int cap);
>  int security_sysctl(struct ctl_table *table, int op);
> @@ -1856,9 +1856,9 @@ static inline int security_capset(struct cred *new,
>  	return cap_capset(new, old, effective, inheritable, permitted);
>  }
>  
> -static inline int security_capable(int cap)
> +static inline int security_capable(const struct cred *cred, int cap)
>  {
> -	return cap_capable(current, current_cred(), cap, SECURITY_CAP_AUDIT);
> +	return cap_capable(current, cred, cap, SECURITY_CAP_AUDIT);
>  }
>  
>  static inline int security_real_capable(struct task_struct *tsk, int cap)
> diff --git a/kernel/capability.c b/kernel/capability.c
> index 2f05303..9e9385f 100644
> --- a/kernel/capability.c
> +++ b/kernel/capability.c
> @@ -306,7 +306,7 @@ int capable(int cap)
>  		BUG();
>  	}
>  
> -	if (security_capable(cap) == 0) {
> +	if (security_capable(current_cred(), cap) == 0) {
>  		current->flags |= PF_SUPERPRIV;
>  		return 1;
>  	}
> diff --git a/security/security.c b/security/security.c
> index 739e403..7b7308a 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -154,10 +154,9 @@ int security_capset(struct cred *new, const struct cred *old,
>  				    effective, inheritable, permitted);
>  }
>  
> -int security_capable(int cap)
> +int security_capable(const struct cred *cred, int cap)
>  {
> -	return security_ops->capable(current, current_cred(), cap,
> -				     SECURITY_CAP_AUDIT);
> +	return security_ops->capable(current, cred, cap, SECURITY_CAP_AUDIT);
>  }
>  
>  int security_real_capable(struct task_struct *tsk, int cap)