Merge "lib: align source before using optimized implementation" (bcde0fdb) · Commits · e / devices / android_kernel_xiaomi_markw

lib/strncpy_from_user.c

+17 −0

Original line number	Diff line number	Diff line
		@@ -13,6 +13,8 @@
		(((long) dst \| (long) src) & (sizeof(long) - 1))
		#endif

		#define CHECK_ALIGN(v, a) ((((unsigned long)(v)) & ((a) - 1)) == 0)

		/*
		* Do a strncpy, return length of string without final '\0'.
		* 'count' is the user-supplied count (return 'count' if we
		@@ -34,6 +36,21 @@ static inline long do_strncpy_from_user(char dst, const char __user src, long
		if (IS_UNALIGNED(src, dst))
		goto byte_at_a_time;

		/* Copy a byte at a time until we align to 8 bytes */
		while (max && (!CHECK_ALIGN(src + res, 8))) {
		char c;
		int ret;

		ret = __get_user(c, src + res);
		if (ret)
		return -ret;
		dst[res] = c;
		if (!c)
		return res;
		res++;
		max--;
		}

		while (max >= sizeof(unsigned long)) {
		unsigned long c, data;