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/*
* iovec manipulation routines.
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Fixes:
* Andrew Lunn : Errors in iovec copying.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/net.h>
#include <asm/segment.h>
extern inline int min(int x, int y)
{
return x>y?y:x;
}
int verify_iovec(struct msghdr *m, struct iovec *iov, char *address, int mode)
{
int err=0;
int len=0;
int ct;
if(m->msg_name!=NULL)
{
if(mode==VERIFY_READ) {
err=move_addr_to_kernel(m->msg_name, m->msg_namelen, address);
} else
err=verify_area(mode, m->msg_name, m->msg_namelen);
if(err<0)
return err;
m->msg_name = address;
}
if(m->msg_control!=NULL)
{
err=verify_area(mode, m->msg_control, m->msg_controllen);
if(err)
return err;
}
for(ct=0;ct<m->msg_iovlen;ct++)
{
err=verify_area(VERIFY_READ, &m->msg_iov[ct], sizeof(struct iovec));
if(err)
return err;
memcpy_fromfs(&iov[ct], &m->msg_iov[ct], sizeof(struct iovec));
err=verify_area(mode, iov[ct].iov_base, iov[ct].iov_len);
if(err)
return err;
len+=iov[ct].iov_len;
}
m->msg_iov=&iov[0];
return len;
}
/*
* Copy kernel to iovec.
*/
void memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len)
{
while(len>0)
{
if(iov->iov_len)
{
int copy = min(iov->iov_len,len);
memcpy_tofs(iov->iov_base,kdata,copy);
kdata+=copy;
len-=copy;
iov->iov_len-=copy;
iov->iov_base+=copy;
}
iov++;
}
}
/*
* Copy iovec to kernel.
*/
void memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len)
{
while(len>0)
{
if(iov->iov_len)
{
int copy=min(len,iov->iov_len);
memcpy_fromfs(kdata, iov->iov_base, copy);
len-=copy;
kdata+=copy;
iov->iov_base+=copy;
iov->iov_len-=copy;
}
iov++;
}
}
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