x86: switch to RAW_COPY_USER

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
2017-03-25 19:33:21 -04:00
parent a41e0d7542
commit beba3a20bf
6 changed files with 24 additions and 395 deletions

View File

@@ -8,113 +8,48 @@
#include <asm/asm.h>
#include <asm/page.h>
unsigned long __must_check __copy_to_user_ll
(void __user *to, const void *from, unsigned long n);
unsigned long __must_check __copy_from_user_ll
(void *to, const void __user *from, unsigned long n);
unsigned long __must_check __copy_from_user_ll_nozero
(void *to, const void __user *from, unsigned long n);
unsigned long __must_check __copy_user_ll
(void *to, const void *from, unsigned long n);
unsigned long __must_check __copy_from_user_ll_nocache_nozero
(void *to, const void __user *from, unsigned long n);
/**
* __copy_to_user_inatomic: - Copy a block of data into user space, with less checking.
* @to: Destination address, in user space.
* @from: Source address, in kernel space.
* @n: Number of bytes to copy.
*
* Context: User context only.
*
* Copy data from kernel space to user space. Caller must check
* the specified block with access_ok() before calling this function.
* The caller should also make sure he pins the user space address
* so that we don't result in page fault and sleep.
*/
static __always_inline unsigned long __must_check
__copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
check_object_size(from, n, true);
return __copy_to_user_ll(to, from, n);
}
/**
* __copy_to_user: - Copy a block of data into user space, with less checking.
* @to: Destination address, in user space.
* @from: Source address, in kernel space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from kernel space to user space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be copied.
* On success, this will be zero.
*/
static __always_inline unsigned long __must_check
__copy_to_user(void __user *to, const void *from, unsigned long n)
{
might_fault();
return __copy_to_user_inatomic(to, from, n);
return __copy_user_ll((__force void *)to, from, n);
}
static __always_inline unsigned long
__copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
return __copy_from_user_ll_nozero(to, from, n);
}
/**
* __copy_from_user: - Copy a block of data from user space, with less checking.
* @to: Destination address, in kernel space.
* @from: Source address, in user space.
* @n: Number of bytes to copy.
*
* Context: User context only. This function may sleep if pagefaults are
* enabled.
*
* Copy data from user space to kernel space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be copied.
* On success, this will be zero.
*
* If some data could not be copied, this function will pad the copied
* data to the requested size using zero bytes.
*
* An alternate version - __copy_from_user_inatomic() - may be called from
* atomic context and will fail rather than sleep. In this case the
* uncopied bytes will *NOT* be padded with zeros. See fs/filemap.h
* for explanation of why this is needed.
*/
static __always_inline unsigned long
__copy_from_user(void *to, const void __user *from, unsigned long n)
{
might_fault();
check_object_size(to, n, false);
if (__builtin_constant_p(n)) {
unsigned long ret;
switch (n) {
case 1:
ret = 0;
__uaccess_begin();
__get_user_size(*(u8 *)to, from, 1, ret, 1);
__get_user_asm_nozero(*(u8 *)to, from, ret,
"b", "b", "=q", 1);
__uaccess_end();
return ret;
case 2:
ret = 0;
__uaccess_begin();
__get_user_size(*(u16 *)to, from, 2, ret, 2);
__get_user_asm_nozero(*(u16 *)to, from, ret,
"w", "w", "=r", 2);
__uaccess_end();
return ret;
case 4:
ret = 0;
__uaccess_begin();
__get_user_size(*(u32 *)to, from, 4, ret, 4);
__get_user_asm_nozero(*(u32 *)to, from, ret,
"l", "k", "=r", 4);
__uaccess_end();
return ret;
}
}
return __copy_from_user_ll(to, from, n);
return __copy_user_ll(to, (__force const void *)from, n);
}
static __always_inline unsigned long