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v3.5.6
 
  1/*
  2 * linux/ipc/msgutil.c
  3 * Copyright (C) 1999, 2004 Manfred Spraul
  4 *
  5 * This file is released under GNU General Public Licence version 2 or
  6 * (at your option) any later version.
  7 *
  8 * See the file COPYING for more details.
  9 */
 10
 11#include <linux/spinlock.h>
 12#include <linux/init.h>
 13#include <linux/security.h>
 14#include <linux/slab.h>
 15#include <linux/ipc.h>
 16#include <linux/msg.h>
 17#include <linux/ipc_namespace.h>
 18#include <linux/utsname.h>
 19#include <asm/uaccess.h>
 
 
 20
 21#include "util.h"
 22
 23DEFINE_SPINLOCK(mq_lock);
 24
 25/*
 26 * The next 2 defines are here bc this is the only file
 27 * compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE
 28 * and not CONFIG_IPC_NS.
 29 */
 30struct ipc_namespace init_ipc_ns = {
 31	.count		= ATOMIC_INIT(1),
 32	.user_ns = &init_user_ns,
 
 
 
 
 33};
 34
 35atomic_t nr_ipc_ns = ATOMIC_INIT(1);
 36
 37struct msg_msgseg {
 38	struct msg_msgseg* next;
 39	/* the next part of the message follows immediately */
 40};
 41
 42#define DATALEN_MSG	(PAGE_SIZE-sizeof(struct msg_msg))
 43#define DATALEN_SEG	(PAGE_SIZE-sizeof(struct msg_msgseg))
 
 44
 45struct msg_msg *load_msg(const void __user *src, int len)
 46{
 47	struct msg_msg *msg;
 48	struct msg_msgseg **pseg;
 49	int err;
 50	int alen;
 51
 52	alen = len;
 53	if (alen > DATALEN_MSG)
 54		alen = DATALEN_MSG;
 55
 56	msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL);
 
 57	if (msg == NULL)
 58		return ERR_PTR(-ENOMEM);
 59
 60	msg->next = NULL;
 61	msg->security = NULL;
 62
 63	if (copy_from_user(msg + 1, src, alen)) {
 64		err = -EFAULT;
 65		goto out_err;
 66	}
 67
 68	len -= alen;
 69	src = ((char __user *)src) + alen;
 70	pseg = &msg->next;
 71	while (len > 0) {
 72		struct msg_msgseg *seg;
 73		alen = len;
 74		if (alen > DATALEN_SEG)
 75			alen = DATALEN_SEG;
 76		seg = kmalloc(sizeof(*seg) + alen,
 77						 GFP_KERNEL);
 78		if (seg == NULL) {
 79			err = -ENOMEM;
 80			goto out_err;
 81		}
 82		*pseg = seg;
 83		seg->next = NULL;
 84		if (copy_from_user(seg + 1, src, alen)) {
 85			err = -EFAULT;
 86			goto out_err;
 87		}
 88		pseg = &seg->next;
 89		len -= alen;
 90		src = ((char __user *)src) + alen;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 91	}
 92
 93	err = security_msg_msg_alloc(msg);
 94	if (err)
 95		goto out_err;
 96
 97	return msg;
 98
 99out_err:
100	free_msg(msg);
101	return ERR_PTR(err);
102}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
103
104int store_msg(void __user *dest, struct msg_msg *msg, int len)
 
 
 
 
 
 
105{
106	int alen;
 
 
 
 
 
107	struct msg_msgseg *seg;
108
109	alen = len;
110	if (alen > DATALEN_MSG)
111		alen = DATALEN_MSG;
112	if (copy_to_user(dest, msg + 1, alen))
113		return -1;
114
115	len -= alen;
116	dest = ((char __user *)dest) + alen;
117	seg = msg->next;
118	while (len > 0) {
119		alen = len;
120		if (alen > DATALEN_SEG)
121			alen = DATALEN_SEG;
122		if (copy_to_user(dest, seg + 1, alen))
123			return -1;
124		len -= alen;
125		dest = ((char __user *)dest) + alen;
126		seg = seg->next;
127	}
128	return 0;
129}
130
131void free_msg(struct msg_msg *msg)
132{
133	struct msg_msgseg *seg;
134
135	security_msg_msg_free(msg);
136
137	seg = msg->next;
138	kfree(msg);
139	while (seg != NULL) {
140		struct msg_msgseg *tmp = seg->next;
 
 
141		kfree(seg);
142		seg = tmp;
143	}
144}
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * linux/ipc/msgutil.c
  4 * Copyright (C) 1999, 2004 Manfred Spraul
 
 
 
 
 
  5 */
  6
  7#include <linux/spinlock.h>
  8#include <linux/init.h>
  9#include <linux/security.h>
 10#include <linux/slab.h>
 11#include <linux/ipc.h>
 12#include <linux/msg.h>
 13#include <linux/ipc_namespace.h>
 14#include <linux/utsname.h>
 15#include <linux/proc_ns.h>
 16#include <linux/uaccess.h>
 17#include <linux/sched.h>
 18
 19#include "util.h"
 20
 21DEFINE_SPINLOCK(mq_lock);
 22
 23/*
 24 * The next 2 defines are here bc this is the only file
 25 * compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE
 26 * and not CONFIG_IPC_NS.
 27 */
 28struct ipc_namespace init_ipc_ns = {
 29	.count		= REFCOUNT_INIT(1),
 30	.user_ns = &init_user_ns,
 31	.ns.inum = PROC_IPC_INIT_INO,
 32#ifdef CONFIG_IPC_NS
 33	.ns.ops = &ipcns_operations,
 34#endif
 35};
 36
 
 
 37struct msg_msgseg {
 38	struct msg_msgseg *next;
 39	/* the next part of the message follows immediately */
 40};
 41
 42#define DATALEN_MSG	((size_t)PAGE_SIZE-sizeof(struct msg_msg))
 43#define DATALEN_SEG	((size_t)PAGE_SIZE-sizeof(struct msg_msgseg))
 44
 45
 46static struct msg_msg *alloc_msg(size_t len)
 47{
 48	struct msg_msg *msg;
 49	struct msg_msgseg **pseg;
 50	size_t alen;
 
 
 
 
 
 51
 52	alen = min(len, DATALEN_MSG);
 53	msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL_ACCOUNT);
 54	if (msg == NULL)
 55		return NULL;
 56
 57	msg->next = NULL;
 58	msg->security = NULL;
 59
 
 
 
 
 
 60	len -= alen;
 
 61	pseg = &msg->next;
 62	while (len > 0) {
 63		struct msg_msgseg *seg;
 64
 65		cond_resched();
 66
 67		alen = min(len, DATALEN_SEG);
 68		seg = kmalloc(sizeof(*seg) + alen, GFP_KERNEL_ACCOUNT);
 69		if (seg == NULL)
 
 70			goto out_err;
 
 71		*pseg = seg;
 72		seg->next = NULL;
 
 
 
 
 73		pseg = &seg->next;
 74		len -= alen;
 75	}
 76
 77	return msg;
 78
 79out_err:
 80	free_msg(msg);
 81	return NULL;
 82}
 83
 84struct msg_msg *load_msg(const void __user *src, size_t len)
 85{
 86	struct msg_msg *msg;
 87	struct msg_msgseg *seg;
 88	int err = -EFAULT;
 89	size_t alen;
 90
 91	msg = alloc_msg(len);
 92	if (msg == NULL)
 93		return ERR_PTR(-ENOMEM);
 94
 95	alen = min(len, DATALEN_MSG);
 96	if (copy_from_user(msg + 1, src, alen))
 97		goto out_err;
 98
 99	for (seg = msg->next; seg != NULL; seg = seg->next) {
100		len -= alen;
101		src = (char __user *)src + alen;
102		alen = min(len, DATALEN_SEG);
103		if (copy_from_user(seg + 1, src, alen))
104			goto out_err;
105	}
106
107	err = security_msg_msg_alloc(msg);
108	if (err)
109		goto out_err;
110
111	return msg;
112
113out_err:
114	free_msg(msg);
115	return ERR_PTR(err);
116}
117#ifdef CONFIG_CHECKPOINT_RESTORE
118struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst)
119{
120	struct msg_msgseg *dst_pseg, *src_pseg;
121	size_t len = src->m_ts;
122	size_t alen;
123
124	if (src->m_ts > dst->m_ts)
125		return ERR_PTR(-EINVAL);
126
127	alen = min(len, DATALEN_MSG);
128	memcpy(dst + 1, src + 1, alen);
129
130	for (dst_pseg = dst->next, src_pseg = src->next;
131	     src_pseg != NULL;
132	     dst_pseg = dst_pseg->next, src_pseg = src_pseg->next) {
133
134		len -= alen;
135		alen = min(len, DATALEN_SEG);
136		memcpy(dst_pseg + 1, src_pseg + 1, alen);
137	}
138
139	dst->m_type = src->m_type;
140	dst->m_ts = src->m_ts;
141
142	return dst;
143}
144#else
145struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst)
146{
147	return ERR_PTR(-ENOSYS);
148}
149#endif
150int store_msg(void __user *dest, struct msg_msg *msg, size_t len)
151{
152	size_t alen;
153	struct msg_msgseg *seg;
154
155	alen = min(len, DATALEN_MSG);
 
 
156	if (copy_to_user(dest, msg + 1, alen))
157		return -1;
158
159	for (seg = msg->next; seg != NULL; seg = seg->next) {
160		len -= alen;
161		dest = (char __user *)dest + alen;
162		alen = min(len, DATALEN_SEG);
 
 
 
163		if (copy_to_user(dest, seg + 1, alen))
164			return -1;
 
 
 
165	}
166	return 0;
167}
168
169void free_msg(struct msg_msg *msg)
170{
171	struct msg_msgseg *seg;
172
173	security_msg_msg_free(msg);
174
175	seg = msg->next;
176	kfree(msg);
177	while (seg != NULL) {
178		struct msg_msgseg *tmp = seg->next;
179
180		cond_resched();
181		kfree(seg);
182		seg = tmp;
183	}
184}