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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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3bd080e4d8
Write-only variable. Link: http://lkml.kernel.org/r/20160708214356.GA6785@p183.telecom.by Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
183 lines
3.6 KiB
C
183 lines
3.6 KiB
C
/*
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* linux/ipc/msgutil.c
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* Copyright (C) 1999, 2004 Manfred Spraul
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*
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* This file is released under GNU General Public Licence version 2 or
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* (at your option) any later version.
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*
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* See the file COPYING for more details.
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*/
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#include <linux/spinlock.h>
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#include <linux/init.h>
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#include <linux/security.h>
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#include <linux/slab.h>
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#include <linux/ipc.h>
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#include <linux/msg.h>
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#include <linux/ipc_namespace.h>
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#include <linux/utsname.h>
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#include <linux/proc_ns.h>
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#include <linux/uaccess.h>
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#include "util.h"
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DEFINE_SPINLOCK(mq_lock);
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/*
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* The next 2 defines are here bc this is the only file
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* compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE
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* and not CONFIG_IPC_NS.
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*/
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struct ipc_namespace init_ipc_ns = {
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.count = ATOMIC_INIT(1),
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.user_ns = &init_user_ns,
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.ns.inum = PROC_IPC_INIT_INO,
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#ifdef CONFIG_IPC_NS
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.ns.ops = &ipcns_operations,
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#endif
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};
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struct msg_msgseg {
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struct msg_msgseg *next;
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/* the next part of the message follows immediately */
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};
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#define DATALEN_MSG ((size_t)PAGE_SIZE-sizeof(struct msg_msg))
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#define DATALEN_SEG ((size_t)PAGE_SIZE-sizeof(struct msg_msgseg))
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static struct msg_msg *alloc_msg(size_t len)
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{
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struct msg_msg *msg;
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struct msg_msgseg **pseg;
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size_t alen;
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alen = min(len, DATALEN_MSG);
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msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL);
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if (msg == NULL)
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return NULL;
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msg->next = NULL;
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msg->security = NULL;
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len -= alen;
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pseg = &msg->next;
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while (len > 0) {
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struct msg_msgseg *seg;
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alen = min(len, DATALEN_SEG);
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seg = kmalloc(sizeof(*seg) + alen, GFP_KERNEL);
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if (seg == NULL)
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goto out_err;
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*pseg = seg;
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seg->next = NULL;
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pseg = &seg->next;
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len -= alen;
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}
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return msg;
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out_err:
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free_msg(msg);
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return NULL;
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}
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struct msg_msg *load_msg(const void __user *src, size_t len)
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{
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struct msg_msg *msg;
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struct msg_msgseg *seg;
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int err = -EFAULT;
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size_t alen;
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msg = alloc_msg(len);
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if (msg == NULL)
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return ERR_PTR(-ENOMEM);
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alen = min(len, DATALEN_MSG);
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if (copy_from_user(msg + 1, src, alen))
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goto out_err;
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for (seg = msg->next; seg != NULL; seg = seg->next) {
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len -= alen;
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src = (char __user *)src + alen;
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alen = min(len, DATALEN_SEG);
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if (copy_from_user(seg + 1, src, alen))
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goto out_err;
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}
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err = security_msg_msg_alloc(msg);
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if (err)
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goto out_err;
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return msg;
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out_err:
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free_msg(msg);
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return ERR_PTR(err);
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}
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#ifdef CONFIG_CHECKPOINT_RESTORE
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struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst)
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{
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struct msg_msgseg *dst_pseg, *src_pseg;
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size_t len = src->m_ts;
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size_t alen;
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if (src->m_ts > dst->m_ts)
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return ERR_PTR(-EINVAL);
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alen = min(len, DATALEN_MSG);
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memcpy(dst + 1, src + 1, alen);
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for (dst_pseg = dst->next, src_pseg = src->next;
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src_pseg != NULL;
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dst_pseg = dst_pseg->next, src_pseg = src_pseg->next) {
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len -= alen;
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alen = min(len, DATALEN_SEG);
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memcpy(dst_pseg + 1, src_pseg + 1, alen);
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}
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dst->m_type = src->m_type;
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dst->m_ts = src->m_ts;
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return dst;
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}
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#else
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struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst)
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{
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return ERR_PTR(-ENOSYS);
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}
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#endif
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int store_msg(void __user *dest, struct msg_msg *msg, size_t len)
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{
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size_t alen;
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struct msg_msgseg *seg;
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alen = min(len, DATALEN_MSG);
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if (copy_to_user(dest, msg + 1, alen))
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return -1;
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for (seg = msg->next; seg != NULL; seg = seg->next) {
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len -= alen;
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dest = (char __user *)dest + alen;
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alen = min(len, DATALEN_SEG);
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if (copy_to_user(dest, seg + 1, alen))
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return -1;
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}
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return 0;
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}
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void free_msg(struct msg_msg *msg)
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{
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struct msg_msgseg *seg;
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security_msg_msg_free(msg);
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seg = msg->next;
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kfree(msg);
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while (seg != NULL) {
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struct msg_msgseg *tmp = seg->next;
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kfree(seg);
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seg = tmp;
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}
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}
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