[PATCH] security: remove unused parameter from security_task_setscheduler()

From: KOSAKI Motohiro
Date: Thu Oct 14 2010 - 15:21:18 EST


All security modules shouldn't change sched_param parameter of
security_task_setscheduler(). This is not only meaningless, but also
make a harmful result if caller pass a static variable.

This patch remove policy and sched_param parameter from
security_task_setscheduler() becuase none of security module is
using it.

Cc: James Morris <jmorris@xxxxxxxxx>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
---
arch/mips/kernel/mips-mt-fpaff.c | 2 +-
include/linux/security.h | 14 +++++---------
kernel/cpuset.c | 4 ++--
kernel/sched.c | 4 ++--
security/commoncap.c | 5 +----
security/security.c | 5 ++---
security/selinux/hooks.c | 4 ++--
security/smack/smack_lsm.c | 5 ++---
8 files changed, 17 insertions(+), 26 deletions(-)

diff --git a/arch/mips/kernel/mips-mt-fpaff.c b/arch/mips/kernel/mips-mt-fpaff.c
index 2340f11..9a526ba 100644
--- a/arch/mips/kernel/mips-mt-fpaff.c
+++ b/arch/mips/kernel/mips-mt-fpaff.c
@@ -103,7 +103,7 @@ asmlinkage long mipsmt_sys_sched_setaffinity(pid_t pid, unsigned int len,
if (!check_same_owner(p) && !capable(CAP_SYS_NICE))
goto out_unlock;

- retval = security_task_setscheduler(p, 0, NULL);
+ retval = security_task_setscheduler(p)
if (retval)
goto out_unlock;

diff --git a/include/linux/security.h b/include/linux/security.h
index a22219a..294a0b2 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -74,7 +74,7 @@ extern int cap_file_mmap(struct file *file, unsigned long reqprot,
extern int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags);
extern int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
unsigned long arg4, unsigned long arg5);
-extern int cap_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp);
+extern int cap_task_setscheduler(struct task_struct *p);
extern int cap_task_setioprio(struct task_struct *p, int ioprio);
extern int cap_task_setnice(struct task_struct *p, int nice);
extern int cap_syslog(int type, bool from_file);
@@ -1501,8 +1501,7 @@ struct security_operations {
int (*task_getioprio) (struct task_struct *p);
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_setscheduler) (struct task_struct *p);
int (*task_getscheduler) (struct task_struct *p);
int (*task_movememory) (struct task_struct *p);
int (*task_kill) (struct task_struct *p,
@@ -1752,8 +1751,7 @@ int security_task_setioprio(struct task_struct *p, int ioprio);
int security_task_getioprio(struct task_struct *p);
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_setscheduler(struct task_struct *p);
int security_task_getscheduler(struct task_struct *p);
int security_task_movememory(struct task_struct *p);
int security_task_kill(struct task_struct *p, struct siginfo *info,
@@ -2320,11 +2318,9 @@ static inline int security_task_setrlimit(struct task_struct *p,
return 0;
}

-static inline int security_task_setscheduler(struct task_struct *p,
- int policy,
- struct sched_param *lp)
+static inline int security_task_setscheduler(struct task_struct *p)
{
- return cap_task_setscheduler(p, policy, lp);
+ return cap_task_setscheduler(p);
}

static inline int security_task_getscheduler(struct task_struct *p)
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index b23c097..51b143e 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1397,7 +1397,7 @@ static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cont,
if (tsk->flags & PF_THREAD_BOUND)
return -EINVAL;

- ret = security_task_setscheduler(tsk, 0, NULL);
+ ret = security_task_setscheduler(tsk);
if (ret)
return ret;
if (threadgroup) {
@@ -1405,7 +1405,7 @@ static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cont,

rcu_read_lock();
list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) {
- ret = security_task_setscheduler(c, 0, NULL);
+ ret = security_task_setscheduler(c);
if (ret) {
rcu_read_unlock();
return ret;
diff --git a/kernel/sched.c b/kernel/sched.c
index dc85ceb..df6579d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4645,7 +4645,7 @@ recheck:
}

if (user) {
- retval = security_task_setscheduler(p, policy, param);
+ retval = security_task_setscheduler(p);
if (retval)
return retval;
}
@@ -4887,7 +4887,7 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
if (!check_same_owner(p) && !capable(CAP_SYS_NICE))
goto out_unlock;

- retval = security_task_setscheduler(p, 0, NULL);
+ retval = security_task_setscheduler(p);
if (retval)
goto out_unlock;

diff --git a/security/commoncap.c b/security/commoncap.c
index 9d172e6..5e632b4 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -719,14 +719,11 @@ static int cap_safe_nice(struct task_struct *p)
/**
* cap_task_setscheduler - Detemine if scheduler policy change is permitted
* @p: The task to affect
- * @policy: The policy to effect
- * @lp: The parameters to the scheduling policy
*
* Detemine if the requested scheduler policy change is permitted for the
* specified task, returning 0 if permission is granted, -ve if denied.
*/
-int cap_task_setscheduler(struct task_struct *p, int policy,
- struct sched_param *lp)
+int cap_task_setscheduler(struct task_struct *p)
{
return cap_safe_nice(p);
}
diff --git a/security/security.c b/security/security.c
index c53949f..34a3f2c 100644
--- a/security/security.c
+++ b/security/security.c
@@ -786,10 +786,9 @@ int security_task_setrlimit(struct task_struct *p, unsigned int resource,
return security_ops->task_setrlimit(p, resource, new_rlim);
}

-int security_task_setscheduler(struct task_struct *p,
- int policy, struct sched_param *lp)
+int security_task_setscheduler(struct task_struct *p)
{
- return security_ops->task_setscheduler(p, policy, lp);
+ return security_ops->task_setscheduler(p);
}

int security_task_getscheduler(struct task_struct *p)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 4796ddd..db2b331 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3354,11 +3354,11 @@ static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
return 0;
}

-static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
+static int selinux_task_setscheduler(struct task_struct *p)
{
int rc;

- rc = cap_task_setscheduler(p, policy, lp);
+ rc = cap_task_setscheduler(p);
if (rc)
return rc;

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index c448d57..174aec4 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1281,12 +1281,11 @@ static int smack_task_getioprio(struct task_struct *p)
*
* Return 0 if read access is permitted
*/
-static int smack_task_setscheduler(struct task_struct *p, int policy,
- struct sched_param *lp)
+static int smack_task_setscheduler(struct task_struct *p)
{
int rc;

- rc = cap_task_setscheduler(p, policy, lp);
+ rc = cap_task_setscheduler(p);
if (rc == 0)
rc = smk_curacc_on_task(p, MAY_WRITE);
return rc;
--
1.6.5.2



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