* This needs 33-bit arithmetic. We have a carry...
*/
#define __range_ok(addr,size) ({ \
- unsigned long flag,sum; \
+ unsigned long flag,roksum; \
__chk_user_ptr(addr); \
asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0" \
- :"=&r" (flag), "=r" (sum) \
+ :"=&r" (flag), "=r" (roksum) \
:"1" (addr),"g" ((int)(size)),"rm" (current_thread_info()->addr_limit.seg)); \
flag; })
unsigned long __must_check __copy_from_user_ll_nocache_nozero(void *to,
const void __user *from, unsigned long n);
-/*
- * Here we special-case 1, 2 and 4-byte copy_*_user invocations. On a fault
- * we return the initial request size (1, 2 or 4), as copy_*_user should do.
- * If a store crosses a page boundary and gets a fault, the x86 will not write
- * anything, so this is accurate.
- */
-
/**
- * __copy_to_user: - Copy a block of data into user space, with less checking.
+ * __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. This function may sleep.
+ * 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 the we don't result in page fault and sleep.
*
- * Returns number of bytes that could not be copied.
- * On success, this will be zero.
+ * Here we special-case 1, 2 and 4-byte copy_*_user invocations. On a fault
+ * we return the initial request size (1, 2 or 4), as copy_*_user should do.
+ * If a store crosses a page boundary and gets a fault, the x86 will not write
+ * anything, so this is accurate.
*/
+
static __always_inline unsigned long __must_check
__copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
{
return __copy_to_user_ll(to, from, n);
}
-static __always_inline unsigned long __must_check
-__copy_to_user(void __user *to, const void *from, unsigned long n)
-{
- might_sleep();
- return __copy_to_user_inatomic(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.
+ * __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.
*
- * Copy data from user space to kernel space. Caller must check
+ * 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.
- *
- * 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 __must_check
+__copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ might_sleep();
+ return __copy_to_user_inatomic(to, from, n);
+}
+
static __always_inline unsigned long
__copy_from_user_inatomic(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.
+ *
+ * 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)
{
* If there is a limit on the length of a valid string, you may wish to
* consider using strnlen_user() instead.
*/
-#define strlen_user(str) strnlen_user(str, ~0UL >> 1)
+#define strlen_user(str) strnlen_user(str, LONG_MAX)
long strnlen_user(const char __user *str, long n);
unsigned long __must_check clear_user(void __user *mem, unsigned long len);