Re: [PATCH 2/6] SECURITY: add task_struct to setrlimit

From: Eric Paris
Date: Mon Aug 31 2009 - 15:08:20 EST


On Mon, 2009-08-31 at 20:56 +0200, Jiri Slaby wrote:
> Add task_struct to task_setrlimit of security_operations to be able to set
> rlimit of different task than current.
>
> Signed-off-by: Jiri Slaby <jirislaby@xxxxxxxxx>
> Cc: James Morris <jmorris@xxxxxxxxx>
> Cc: Eric Paris <eparis@xxxxxxxxxxxxxx>

It looks ok to me. We still seem to have complete SELinux control and I
don't see that you missed anything elsewhere in the security subsystem.

Acked-by: Eric Paris <eparis@xxxxxxxxxx>


> ---
> include/linux/security.h | 9 ++++++---
> kernel/sys.c | 2 +-
> security/capability.c | 3 ++-
> security/security.c | 5 +++--
> security/selinux/hooks.c | 7 ++++---
> 5 files changed, 16 insertions(+), 10 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 0f81525..880a21c 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -1520,7 +1520,8 @@ struct security_operations {
> int (*task_setnice) (struct task_struct *p, int nice);
> int (*task_setioprio) (struct task_struct *p, int ioprio);
> int (*task_getioprio) (struct task_struct *p);
> - int (*task_setrlimit) (unsigned int resource, struct rlimit *new_rlim);
> + int (*task_setrlimit) (struct task_struct *p, unsigned int resource,
> + struct rlimit *new_rlim);
> int (*task_setscheduler) (struct task_struct *p, int policy,
> struct sched_param *lp);
> int (*task_getscheduler) (struct task_struct *p);
> @@ -1775,7 +1776,8 @@ int security_task_setgroups(struct group_info *group_info);
> int security_task_setnice(struct task_struct *p, int nice);
> int security_task_setioprio(struct task_struct *p, int ioprio);
> int security_task_getioprio(struct task_struct *p);
> -int security_task_setrlimit(unsigned int resource, struct rlimit *new_rlim);
> +int security_task_setrlimit(struct task_struct *p, unsigned int resource,
> + struct rlimit *new_rlim);
> int security_task_setscheduler(struct task_struct *p,
> int policy, struct sched_param *lp);
> int security_task_getscheduler(struct task_struct *p);
> @@ -2385,7 +2387,8 @@ static inline int security_task_getioprio(struct task_struct *p)
> return 0;
> }
>
> -static inline int security_task_setrlimit(unsigned int resource,
> +static inline int security_task_setrlimit(struct task_struct *p,
> + unsigned int resource,
> struct rlimit *new_rlim)
> {
> return 0;
> diff --git a/kernel/sys.c b/kernel/sys.c
> index a7e36b6..ae7be2e 100644
> --- a/kernel/sys.c
> +++ b/kernel/sys.c
> @@ -1254,7 +1254,7 @@ SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
> if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open)
> return -EPERM;
>
> - retval = security_task_setrlimit(resource, &new_rlim);
> + retval = security_task_setrlimit(current, resource, &new_rlim);
> if (retval)
> return retval;
>
> diff --git a/security/capability.c b/security/capability.c
> index 6c38f4d..90d6daf 100644
> --- a/security/capability.c
> +++ b/security/capability.c
> @@ -447,7 +447,8 @@ static int cap_task_getioprio(struct task_struct *p)
> return 0;
> }
>
> -static int cap_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
> +static int cap_task_setrlimit(struct task_struct *p, unsigned int resource,
> + struct rlimit *new_rlim)
> {
> return 0;
> }
> diff --git a/security/security.c b/security/security.c
> index 0b7f9eb..b2c21dc 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -779,9 +779,10 @@ int security_task_getioprio(struct task_struct *p)
> return security_ops->task_getioprio(p);
> }
>
> -int security_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
> +int security_task_setrlimit(struct task_struct *p, unsigned int resource,
> + struct rlimit *new_rlim)
> {
> - return security_ops->task_setrlimit(resource, new_rlim);
> + return security_ops->task_setrlimit(p, resource, new_rlim);
> }
>
> int security_task_setscheduler(struct task_struct *p,
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index 496e626..839622a 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -3355,16 +3355,17 @@ static int selinux_task_getioprio(struct task_struct *p)
> return current_has_perm(p, PROCESS__GETSCHED);
> }
>
> -static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
> +static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
> + struct rlimit *new_rlim)
> {
> - struct rlimit *old_rlim = current->signal->rlim + resource;
> + struct rlimit *old_rlim = p->signal->rlim + resource;
>
> /* Control the ability to change the hard limit (whether
> lowering or raising it), so that the hard limit can
> later be used as a safe reset point for the soft limit
> upon context transitions. See selinux_bprm_committing_creds. */
> if (old_rlim->rlim_max != new_rlim->rlim_max)
> - return current_has_perm(current, PROCESS__SETRLIMIT);
> + return current_has_perm(p, PROCESS__SETRLIMIT);
>
> return 0;
> }


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