arm64: dts: rockchip: add efuse device node for rk3366

[firefly-linux-kernel-4.4.55.git] / lib / strncpy_from_user.c

diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c
index ead8c4a068d12a5f1f9967d448130337cc870ef1..05efc1fa97f08941d763996d38ce08afbbaba459 100644 (file)
--- a/lib/strncpy_from_user.c
+++ b/lib/strncpy_from_user.c
@@ -1,5 +1,6 @@
 #include <linux/compiler.h>
 #include <linux/export.h>
+#include <linux/thread_info.h>
 #include <linux/uaccess.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
@@ -39,8 +40,8 @@ static inline long do_strncpy_from_user(char *dst, const char __user *src, long
                unsigned long c, data;
 
                /* Fall back to byte-at-a-time if we get a page fault */
-               if (unlikely(__get_user(c,(unsigned long __user *)(src+res))))
-                       break;
+               unsafe_get_user(c, (unsigned long __user *)(src+res), byte_at_a_time);
+
                *(unsigned long *)(dst+res) = c;
                if (has_zero(c, &data, &constants)) {
                        data = prep_zero_mask(c, data, &constants);
@@ -55,8 +56,7 @@ byte_at_a_time:
        while (max) {
                char c;
 
-               if (unlikely(__get_user(c,src+res)))
-                       return -EFAULT;
+               unsafe_get_user(c,src+res, efault);
                dst[res] = c;
                if (!c)
                        return res;
@@ -75,6 +75,7 @@ byte_at_a_time:
         * Nope: we hit the address space limit, and we still had more
         * characters the caller would have wanted. That's an EFAULT.
         */
+efault:
        return -EFAULT;
 }
 
@@ -107,49 +108,14 @@ long strncpy_from_user(char *dst, const char __user *src, long count)
        src_addr = (unsigned long)src;
        if (likely(src_addr < max_addr)) {
                unsigned long max = max_addr - src_addr;
-               return do_strncpy_from_user(dst, src, count, max);
+               long retval;
+
+               check_object_size(dst, count, false);
+               user_access_begin();
+               retval = do_strncpy_from_user(dst, src, count, max);
+               user_access_end();
+               return retval;
        }
        return -EFAULT;
 }
 EXPORT_SYMBOL(strncpy_from_user);
-
-/**
- * strncpy_from_unsafe: - Copy a NUL terminated string from unsafe address.
- * @dst:   Destination address, in kernel space.  This buffer must be at
- *         least @count bytes long.
- * @src:   Unsafe address.
- * @count: Maximum number of bytes to copy, including the trailing NUL.
- *
- * Copies a NUL-terminated string from unsafe address to kernel buffer.
- *
- * On success, returns the length of the string INCLUDING the trailing NUL.
- *
- * If access fails, returns -EFAULT (some data may have been copied
- * and the trailing NUL added).
- *
- * If @count is smaller than the length of the string, copies @count-1 bytes,
- * sets the last byte of @dst buffer to NUL and returns @count.
- */
-long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count)
-{
-       mm_segment_t old_fs = get_fs();
-       const void *src = unsafe_addr;
-       long ret;
-
-       if (unlikely(count <= 0))
-               return 0;
-
-       set_fs(KERNEL_DS);
-       pagefault_disable();
-
-       do {
-               ret = __copy_from_user_inatomic(dst++,
-                                               (const void __user __force *)src++, 1);
-       } while (dst[-1] && ret == 0 && src - unsafe_addr < count);
-
-       dst[-1] = '\0';
-       pagefault_enable();
-       set_fs(old_fs);
-
-       return ret < 0 ? ret : src - unsafe_addr;
-}