* 30 May 2002: Cleanup, Robert M. Love <rml@tech9.net>
*/
+#include <linux/capability.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/security.h>
+#include <linux/syscalls.h>
#include <asm/uaccess.h>
unsigned securebits = SECUREBITS_DEFAULT; /* systemwide security settings */
EXPORT_SYMBOL(cap_bset);
/*
- * This global lock protects task->cap_* for all tasks including current.
+ * This lock protects task->cap_* for all tasks including current.
* Locking rule: acquire this prior to tasklist_lock.
*/
-spinlock_t task_capability_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(task_capability_lock);
/*
* For sys_getproccap() and sys_setproccap(), any of the three
* uninteresting and/or not to be changed.
*/
-/*
+/**
* sys_capget - get the capabilities of a given process.
+ * @header: pointer to struct that contains capability version and
+ * target pid data
+ * @dataptr: pointer to struct that contains the effective, permitted,
+ * and inheritable capabilities that are returned
+ *
+ * Returns 0 on success and < 0 on error.
*/
asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr)
{
int ret = 0;
pid_t pid;
__u32 version;
- task_t *target;
+ struct task_struct *target;
struct __user_cap_data_struct data;
if (get_user(version, &header->version))
* cap_set_pg - set capabilities for all processes in a given process
* group. We call this holding task_capability_lock and tasklist_lock.
*/
-static inline void cap_set_pg(int pgrp, kernel_cap_t *effective,
+static inline int cap_set_pg(int pgrp, kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted)
{
- task_t *g, *target;
- struct list_head *l;
- struct pid *pid;
+ struct task_struct *g, *target;
+ int ret = -EPERM;
+ int found = 0;
- for_each_task_pid(pgrp, PIDTYPE_PGID, g, l, pid) {
+ do_each_task_pid(pgrp, PIDTYPE_PGID, g) {
target = g;
- while_each_thread(g, target)
- security_capset_set(target, effective, inheritable, permitted);
- }
+ while_each_thread(g, target) {
+ if (!security_capset_check(target, effective,
+ inheritable,
+ permitted)) {
+ security_capset_set(target, effective,
+ inheritable,
+ permitted);
+ ret = 0;
+ }
+ found = 1;
+ }
+ } while_each_task_pid(pgrp, PIDTYPE_PGID, g);
+
+ if (!found)
+ ret = 0;
+ return ret;
}
/*
* cap_set_all - set capabilities for all processes other than init
* and self. We call this holding task_capability_lock and tasklist_lock.
*/
-static inline void cap_set_all(kernel_cap_t *effective,
+static inline int cap_set_all(kernel_cap_t *effective,
kernel_cap_t *inheritable,
kernel_cap_t *permitted)
{
- task_t *g, *target;
+ struct task_struct *g, *target;
+ int ret = -EPERM;
+ int found = 0;
do_each_thread(g, target) {
if (target == current || target->pid == 1)
continue;
+ found = 1;
+ if (security_capset_check(target, effective, inheritable,
+ permitted))
+ continue;
+ ret = 0;
security_capset_set(target, effective, inheritable, permitted);
} while_each_thread(g, target);
+
+ if (!found)
+ ret = 0;
+ return ret;
}
-/*
- * sys_capset - set capabilities for a given process, all processes, or all
+/**
+ * sys_capset - set capabilities for a process or a group of processes
+ * @header: pointer to struct that contains capability version and
+ * target pid data
+ * @data: pointer to struct that contains the effective, permitted,
+ * and inheritable capabilities
+ *
+ * Set capabilities for a given process, all processes, or all
* processes in a given process group.
*
* The restrictions on setting capabilities are specified as:
* I: any raised capabilities must be a subset of the (old current) permitted
* P: any raised capabilities must be a subset of the (old current) permitted
* E: must be set to a subset of (new target) permitted
+ *
+ * Returns 0 on success and < 0 on error.
*/
asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
{
kernel_cap_t inheritable, permitted, effective;
__u32 version;
- task_t *target;
+ struct task_struct *target;
int ret;
pid_t pid;
if (get_user(pid, &header->pid))
return -EFAULT;
- if (pid && !capable(CAP_SETPCAP))
+ if (pid && pid != current->pid && !capable(CAP_SETPCAP))
return -EPERM;
if (copy_from_user(&effective, &data->effective, sizeof(effective)) ||
} else
target = current;
- ret = -EPERM;
-
- if (security_capset_check(target, &effective, &inheritable, &permitted))
- goto out;
-
- if (!cap_issubset(inheritable, cap_combine(target->cap_inheritable,
- current->cap_permitted)))
- goto out;
-
- /* verify restrictions on target's new Permitted set */
- if (!cap_issubset(permitted, cap_combine(target->cap_permitted,
- current->cap_permitted)))
- goto out;
-
- /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
- if (!cap_issubset(effective, permitted))
- goto out;
-
ret = 0;
/* having verified that the proposed changes are legal,
we now put them into effect. */
if (pid < 0) {
if (pid == -1) /* all procs other than current and init */
- cap_set_all(&effective, &inheritable, &permitted);
+ ret = cap_set_all(&effective, &inheritable, &permitted);
else /* all procs in process group */
- cap_set_pg(-pid, &effective, &inheritable, &permitted);
+ ret = cap_set_pg(-pid, &effective, &inheritable,
+ &permitted);
} else {
- security_capset_set(target, &effective, &inheritable, &permitted);
+ ret = security_capset_check(target, &effective, &inheritable,
+ &permitted);
+ if (!ret)
+ security_capset_set(target, &effective, &inheritable,
+ &permitted);
}
out:
return ret;
}
+
+int __capable(struct task_struct *t, int cap)
+{
+ if (security_capable(t, cap) == 0) {
+ t->flags |= PF_SUPERPRIV;
+ return 1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(__capable);
+
+int capable(int cap)
+{
+ /* here for now so we don't require task locking */
+ if (vx_check_bit(VXC_CAP_MASK, cap) && !vx_mcaps(1L << cap))
+ return 0;
+ return __capable(current, cap);
+}
+EXPORT_SYMBOL(capable);