#include <asm/uaccess.h>
/*
- * This lock protects task->cap_* for all tasks including current.
- * Locking rule: acquire this prior to tasklist_lock.
- */
-static DEFINE_SPINLOCK(task_capability_lock);
-
-/*
* Leveraged for setting/resetting capabilities
*/
EXPORT_SYMBOL(__cap_full_set);
EXPORT_SYMBOL(__cap_init_eff_set);
-#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
int file_caps_enabled = 1;
static int __init file_caps_disable(char *str)
return 1;
}
__setup("no_file_caps", file_caps_disable);
-#endif
/*
* More recent versions of libcap are available from:
}
/*
- * If we have configured with filesystem capability support, then the
- * only thing that can change the capabilities of the current process
- * is the current process. As such, we can't be in this code at the
- * same time as we are in the process of setting capabilities in this
- * process. The net result is that we can limit our use of locks to
- * when we are reading the caps of another process.
+ * The only thing that can change the capabilities of the current
+ * process is the current process. As such, we can't be in this code
+ * at the same time as we are in the process of setting capabilities
+ * in this process. The net result is that we can limit our use of
+ * locks to when we are reading the caps of another process.
*/
static inline int cap_get_target_pid(pid_t pid, kernel_cap_t *pEp,
kernel_cap_t *pIp, kernel_cap_t *pPp)
if (pid && (pid != task_pid_vnr(current))) {
struct task_struct *target;
- spin_lock(&task_capability_lock);
- read_lock(&tasklist_lock);
+ rcu_read_lock();
target = find_task_by_vpid(pid);
if (!target)
else
ret = security_capget(target, pEp, pIp, pPp);
- read_unlock(&tasklist_lock);
- spin_unlock(&task_capability_lock);
+ rcu_read_unlock();
} else
ret = security_capget(current, pEp, pIp, pPp);
return ret;
}
-/*
- * Atomically modify the effective capabilities returning the original
- * value. No permission check is performed here - it is assumed that the
- * caller is permitted to set the desired effective capabilities.
- */
-kernel_cap_t cap_set_effective(const kernel_cap_t pE_new)
-{
- kernel_cap_t pE_old;
-
- spin_lock(&task_capability_lock);
-
- pE_old = current->cred->cap_effective;
- current->cred->cap_effective = pE_new;
-
- spin_unlock(&task_capability_lock);
-
- return pE_old;
-}
-
-EXPORT_SYMBOL(cap_set_effective);
-
/**
* sys_capget - get the capabilities of a given process.
* @header: pointer to struct that contains capability version and
*
* Returns 0 on success and < 0 on error.
*/
-asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr)
+SYSCALL_DEFINE2(capget, cap_user_header_t, header, cap_user_data_t, dataptr)
{
int ret = 0;
pid_t pid;
kernel_cap_t pE, pI, pP;
ret = cap_validate_magic(header, &tocopy);
- if (ret != 0)
- return ret;
+ if ((dataptr == NULL) || (ret != 0))
+ return ((dataptr == NULL) && (ret == -EINVAL)) ? 0 : ret;
if (get_user(pid, &header->pid))
return -EFAULT;
return -EINVAL;
ret = cap_get_target_pid(pid, &pE, &pI, &pP);
-
if (!ret) {
struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
unsigned i;
*
* Returns 0 on success and < 0 on error.
*/
-asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data)
+SYSCALL_DEFINE2(capset, cap_user_header_t, header, const cap_user_data_t, data)
{
struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
- unsigned i, tocopy;
+ unsigned i, tocopy, copybytes;
kernel_cap_t inheritable, permitted, effective;
+ struct cred *new;
int ret;
pid_t pid;
if (pid != 0 && pid != task_pid_vnr(current))
return -EPERM;
- if (copy_from_user(&kdata, data, tocopy
- * sizeof(struct __user_cap_data_struct)))
+ copybytes = tocopy * sizeof(struct __user_cap_data_struct);
+ if (copybytes > sizeof(kdata))
+ return -EFAULT;
+
+ if (copy_from_user(&kdata, data, copybytes))
return -EFAULT;
for (i = 0; i < tocopy; i++) {
i++;
}
- ret = audit_log_capset(pid, &effective, &inheritable, &permitted);
- if (ret)
- return ret;
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ ret = security_capset(new, current_cred(),
+ &effective, &inheritable, &permitted);
+ if (ret < 0)
+ goto error;
+
+ audit_log_capset(pid, new, current_cred());
+
+ return commit_creds(new);
- /* This lock is required even when filesystem capability support is
- * configured - it protects the sys_capget() call from returning
- * incorrect data in the case that the targeted process is not the
- * current one.
- */
- spin_lock(&task_capability_lock);
-
- ret = security_capset_check(&effective, &inheritable, &permitted);
- /* Having verified that the proposed changes are legal, we now put them
- * into effect.
- */
- if (!ret)
- security_capset_set(&effective, &inheritable, &permitted);
- spin_unlock(&task_capability_lock);
+error:
+ abort_creds(new);
return ret;
}
BUG();
}
- if (has_capability(current, cap)) {
+ if (security_capable(cap) == 0) {
current->flags |= PF_SUPERPRIV;
return 1;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff