145 lines
2.7 KiB
C
145 lines
2.7 KiB
C
/*
|
|
* linux/ipc/msgutil.c
|
|
* Copyright (C) 1999, 2004 Manfred Spraul
|
|
*
|
|
* This file is released under GNU General Public Licence version 2 or
|
|
* (at your option) any later version.
|
|
*
|
|
* See the file COPYING for more details.
|
|
*/
|
|
|
|
#include <linux/spinlock.h>
|
|
#include <linux/init.h>
|
|
#include <linux/security.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/ipc.h>
|
|
#include <linux/msg.h>
|
|
#include <linux/ipc_namespace.h>
|
|
#include <linux/utsname.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#include "util.h"
|
|
|
|
DEFINE_SPINLOCK(mq_lock);
|
|
|
|
/*
|
|
* The next 2 defines are here bc this is the only file
|
|
* compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE
|
|
* and not CONFIG_IPC_NS.
|
|
*/
|
|
struct ipc_namespace init_ipc_ns = {
|
|
.count = ATOMIC_INIT(1),
|
|
.user_ns = &init_user_ns,
|
|
};
|
|
|
|
atomic_t nr_ipc_ns = ATOMIC_INIT(1);
|
|
|
|
struct msg_msgseg {
|
|
struct msg_msgseg* next;
|
|
/* the next part of the message follows immediately */
|
|
};
|
|
|
|
#define DATALEN_MSG (PAGE_SIZE-sizeof(struct msg_msg))
|
|
#define DATALEN_SEG (PAGE_SIZE-sizeof(struct msg_msgseg))
|
|
|
|
struct msg_msg *load_msg(const void __user *src, int len)
|
|
{
|
|
struct msg_msg *msg;
|
|
struct msg_msgseg **pseg;
|
|
int err;
|
|
int alen;
|
|
|
|
alen = len;
|
|
if (alen > DATALEN_MSG)
|
|
alen = DATALEN_MSG;
|
|
|
|
msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL);
|
|
if (msg == NULL)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
msg->next = NULL;
|
|
msg->security = NULL;
|
|
|
|
if (copy_from_user(msg + 1, src, alen)) {
|
|
err = -EFAULT;
|
|
goto out_err;
|
|
}
|
|
|
|
len -= alen;
|
|
src = ((char __user *)src) + alen;
|
|
pseg = &msg->next;
|
|
while (len > 0) {
|
|
struct msg_msgseg *seg;
|
|
alen = len;
|
|
if (alen > DATALEN_SEG)
|
|
alen = DATALEN_SEG;
|
|
seg = kmalloc(sizeof(*seg) + alen,
|
|
GFP_KERNEL);
|
|
if (seg == NULL) {
|
|
err = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
*pseg = seg;
|
|
seg->next = NULL;
|
|
if (copy_from_user(seg + 1, src, alen)) {
|
|
err = -EFAULT;
|
|
goto out_err;
|
|
}
|
|
pseg = &seg->next;
|
|
len -= alen;
|
|
src = ((char __user *)src) + alen;
|
|
}
|
|
|
|
err = security_msg_msg_alloc(msg);
|
|
if (err)
|
|
goto out_err;
|
|
|
|
return msg;
|
|
|
|
out_err:
|
|
free_msg(msg);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
int store_msg(void __user *dest, struct msg_msg *msg, int len)
|
|
{
|
|
int alen;
|
|
struct msg_msgseg *seg;
|
|
|
|
alen = len;
|
|
if (alen > DATALEN_MSG)
|
|
alen = DATALEN_MSG;
|
|
if (copy_to_user(dest, msg + 1, alen))
|
|
return -1;
|
|
|
|
len -= alen;
|
|
dest = ((char __user *)dest) + alen;
|
|
seg = msg->next;
|
|
while (len > 0) {
|
|
alen = len;
|
|
if (alen > DATALEN_SEG)
|
|
alen = DATALEN_SEG;
|
|
if (copy_to_user(dest, seg + 1, alen))
|
|
return -1;
|
|
len -= alen;
|
|
dest = ((char __user *)dest) + alen;
|
|
seg = seg->next;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void free_msg(struct msg_msg *msg)
|
|
{
|
|
struct msg_msgseg *seg;
|
|
|
|
security_msg_msg_free(msg);
|
|
|
|
seg = msg->next;
|
|
kfree(msg);
|
|
while (seg != NULL) {
|
|
struct msg_msgseg *tmp = seg->next;
|
|
kfree(seg);
|
|
seg = tmp;
|
|
}
|
|
}
|