Revision 9de455b20705f36384a711d4a20bcf7ba1ab180b authored by Atsushi Nemoto on 12 December 2006, 17:14:55 UTC, committed by Linus Torvalds on 13 December 2006, 17:27:08 UTC
To allow a more effective copy_user_highpage() on certain architectures, a vma argument is added to the function and cow_user_page() allowing the implementation of these functions to check for the VM_EXEC bit. The main part of this patch was originally written by Ralf Baechle; Atushi Nemoto did the the debugging. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 parent 77fff4a
util.c
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/module.h>
#include <linux/err.h>
#include <asm/uaccess.h>
/**
* __kzalloc - allocate memory. The memory is set to zero.
* @size: how many bytes of memory are required.
* @flags: the type of memory to allocate.
*/
void *__kzalloc(size_t size, gfp_t flags)
{
void *ret = kmalloc_track_caller(size, flags);
if (ret)
memset(ret, 0, size);
return ret;
}
EXPORT_SYMBOL(__kzalloc);
/*
* kstrdup - allocate space for and copy an existing string
*
* @s: the string to duplicate
* @gfp: the GFP mask used in the kmalloc() call when allocating memory
*/
char *kstrdup(const char *s, gfp_t gfp)
{
size_t len;
char *buf;
if (!s)
return NULL;
len = strlen(s) + 1;
buf = kmalloc_track_caller(len, gfp);
if (buf)
memcpy(buf, s, len);
return buf;
}
EXPORT_SYMBOL(kstrdup);
/**
* kmemdup - duplicate region of memory
*
* @src: memory region to duplicate
* @len: memory region length
* @gfp: GFP mask to use
*/
void *kmemdup(const void *src, size_t len, gfp_t gfp)
{
void *p;
p = kmalloc_track_caller(len, gfp);
if (p)
memcpy(p, src, len);
return p;
}
EXPORT_SYMBOL(kmemdup);
/*
* strndup_user - duplicate an existing string from user space
*
* @s: The string to duplicate
* @n: Maximum number of bytes to copy, including the trailing NUL.
*/
char *strndup_user(const char __user *s, long n)
{
char *p;
long length;
length = strnlen_user(s, n);
if (!length)
return ERR_PTR(-EFAULT);
if (length > n)
return ERR_PTR(-EINVAL);
p = kmalloc(length, GFP_KERNEL);
if (!p)
return ERR_PTR(-ENOMEM);
if (copy_from_user(p, s, length)) {
kfree(p);
return ERR_PTR(-EFAULT);
}
p[length - 1] = '\0';
return p;
}
EXPORT_SYMBOL(strndup_user);
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...