mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 13:43:55 +08:00
8990571eb5
The find_pid/_vpid/_pid_ns functions are used to find the struct pid by its id, depending on whic id - global or virtual - is used. The find_vpid() is a macro that pushes the current->nsproxy->pid_ns on the stack to call another function - find_pid_ns(). It turned out, that this dereference together with the push itself cause the kernel text size to grow too much. Move all these out-of-line. Together with the previous patch this saves a bit less that 400 bytes from .text section. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
248 lines
6.1 KiB
C
248 lines
6.1 KiB
C
/*
|
|
* linux/kernel/capability.c
|
|
*
|
|
* Copyright (C) 1997 Andrew Main <zefram@fysh.org>
|
|
*
|
|
* Integrated into 2.1.97+, Andrew G. Morgan <morgan@kernel.org>
|
|
* 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 <linux/pid_namespace.h>
|
|
#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);
|
|
|
|
/*
|
|
* For sys_getproccap() and sys_setproccap(), any of the three
|
|
* capability set pointers may be NULL -- indicating that that set is
|
|
* 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;
|
|
struct task_struct *target;
|
|
struct __user_cap_data_struct data;
|
|
|
|
if (get_user(version, &header->version))
|
|
return -EFAULT;
|
|
|
|
if (version != _LINUX_CAPABILITY_VERSION) {
|
|
if (put_user(_LINUX_CAPABILITY_VERSION, &header->version))
|
|
return -EFAULT;
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (get_user(pid, &header->pid))
|
|
return -EFAULT;
|
|
|
|
if (pid < 0)
|
|
return -EINVAL;
|
|
|
|
spin_lock(&task_capability_lock);
|
|
read_lock(&tasklist_lock);
|
|
|
|
if (pid && pid != task_pid_vnr(current)) {
|
|
target = find_task_by_vpid(pid);
|
|
if (!target) {
|
|
ret = -ESRCH;
|
|
goto out;
|
|
}
|
|
} else
|
|
target = current;
|
|
|
|
ret = security_capget(target, &data.effective, &data.inheritable, &data.permitted);
|
|
|
|
out:
|
|
read_unlock(&tasklist_lock);
|
|
spin_unlock(&task_capability_lock);
|
|
|
|
if (!ret && copy_to_user(dataptr, &data, sizeof data))
|
|
return -EFAULT;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* 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 int cap_set_pg(int pgrp_nr, kernel_cap_t *effective,
|
|
kernel_cap_t *inheritable,
|
|
kernel_cap_t *permitted)
|
|
{
|
|
struct task_struct *g, *target;
|
|
int ret = -EPERM;
|
|
int found = 0;
|
|
struct pid *pgrp;
|
|
|
|
pgrp = find_vpid(pgrp_nr);
|
|
do_each_pid_task(pgrp, PIDTYPE_PGID, g) {
|
|
target = g;
|
|
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_pid_task(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 int cap_set_all(kernel_cap_t *effective,
|
|
kernel_cap_t *inheritable,
|
|
kernel_cap_t *permitted)
|
|
{
|
|
struct task_struct *g, *target;
|
|
int ret = -EPERM;
|
|
int found = 0;
|
|
|
|
do_each_thread(g, target) {
|
|
if (target == current || is_container_init(target->group_leader))
|
|
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 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:
|
|
*
|
|
* [pid is for the 'target' task. 'current' is the calling task.]
|
|
*
|
|
* 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;
|
|
struct task_struct *target;
|
|
int ret;
|
|
pid_t pid;
|
|
|
|
if (get_user(version, &header->version))
|
|
return -EFAULT;
|
|
|
|
if (version != _LINUX_CAPABILITY_VERSION) {
|
|
if (put_user(_LINUX_CAPABILITY_VERSION, &header->version))
|
|
return -EFAULT;
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (get_user(pid, &header->pid))
|
|
return -EFAULT;
|
|
|
|
if (pid && pid != task_pid_vnr(current) && !capable(CAP_SETPCAP))
|
|
return -EPERM;
|
|
|
|
if (copy_from_user(&effective, &data->effective, sizeof(effective)) ||
|
|
copy_from_user(&inheritable, &data->inheritable, sizeof(inheritable)) ||
|
|
copy_from_user(&permitted, &data->permitted, sizeof(permitted)))
|
|
return -EFAULT;
|
|
|
|
spin_lock(&task_capability_lock);
|
|
read_lock(&tasklist_lock);
|
|
|
|
if (pid > 0 && pid != task_pid_vnr(current)) {
|
|
target = find_task_by_vpid(pid);
|
|
if (!target) {
|
|
ret = -ESRCH;
|
|
goto out;
|
|
}
|
|
} else
|
|
target = current;
|
|
|
|
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 */
|
|
ret = cap_set_all(&effective, &inheritable, &permitted);
|
|
|
|
else /* all procs in process group */
|
|
ret = cap_set_pg(-pid, &effective, &inheritable,
|
|
&permitted);
|
|
} else {
|
|
ret = security_capset_check(target, &effective, &inheritable,
|
|
&permitted);
|
|
if (!ret)
|
|
security_capset_set(target, &effective, &inheritable,
|
|
&permitted);
|
|
}
|
|
|
|
out:
|
|
read_unlock(&tasklist_lock);
|
|
spin_unlock(&task_capability_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int __capable(struct task_struct *t, int cap)
|
|
{
|
|
if (security_capable(t, cap) == 0) {
|
|
t->flags |= PF_SUPERPRIV;
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int capable(int cap)
|
|
{
|
|
return __capable(current, cap);
|
|
}
|
|
EXPORT_SYMBOL(capable);
|