From fc8f1d0e51b7135ab336318557181df394455843 Mon Sep 17 00:00:00 2001
From: midipix <writeonce@midipix.org>
Date: Jun 29 2016 23:16:37 +0000
Subject: __ntapi_tt_dev_mount_points_to_statfs: refactor, explicit string comparison.


---

diff --git a/src/fs/ntapi_tt_mount.c b/src/fs/ntapi_tt_mount.c
index 6b6dce2..344f5c1 100644
--- a/src/fs/ntapi_tt_mount.c
+++ b/src/fs/ntapi_tt_mount.c
@@ -280,39 +280,53 @@ int32_t __stdcall	__ntapi_tt_dev_mount_points_to_statfs(
 	__in		nt_mount_points *	mount_points,
 	__in_out	nt_statfs *		statfs)
 {
-	int32_t				status;
-	uint32_t			hash;
-	uint32_t			i;
+	int32_t		status;
+	uint32_t	i;
 
 	nt_mount_mgr_mount_point *	mount_point;
-	char *				symlink;
+	wchar16_t *			symlink;
 
 	mount_point = mount_points->mount_points;
 	statfs->nt_drive_letter = 0;
 
 
 	for (i = 0; i < mount_points->number; i++, mount_point++) {
-		symlink = (char *)mount_points + mount_point->symlink_name_offset;
-
-		/* both prefixes of interest happen to be of the same length */
-		hash = __ntapi->tt_buffer_crc32(
-			0, symlink, __DOS_DEVICES_PREFIX_LEN);
-
-		if (hash == __DOS_DEVICES_PREFIX_HASH)
+		symlink  = (wchar16_t *)mount_points;
+		symlink += mount_point->symlink_name_offset / sizeof(wchar16_t);
+
+		if (symlink[0] != '\\')
+			return NT_STATUS_UNEXPECTED_IO_ERROR;
+
+		if ((symlink[1] == 'D')
+				&& (symlink[2] == 'o')
+				&& (symlink[3] == 's')
+				&& (symlink[4] == 'D')
+				&& (symlink[5] == 'e')
+				&& (symlink[6] == 'v')
+				&& (symlink[7] == 'i')
+				&& (symlink[8] == 'c')
+				&& (symlink[9] == 'e')
+				&& (symlink[10] == 's'))
 			statfs->nt_drive_letter = ((nt_dos_devices_name *)(symlink))->letter;
-		else if (hash == __VOLUME_PATH_PREFIX_HASH) {
-			status = __ntapi_tt_utf16_string_to_guid(
-				(nt_guid_str_utf16 *)(symlink \
-					+ __VOLUME_PATH_PREFIX_LEN \
-					- sizeof(wchar16_t)),
-				&statfs->nt_volume_guid);
-
-			if (status != NT_STATUS_SUCCESS)
+
+		else if ((symlink[1] == '?')
+				&& (symlink[2] == '?')
+				&& (symlink[3] == '\\')
+				&& (symlink[4] == 'V')
+				&& (symlink[5] == 'o')
+				&& (symlink[6] == 'l')
+				&& (symlink[7] == 'u')
+				&& (symlink[8] == 'm')
+				&& (symlink[9] == 'e')
+				&& (symlink[10] == '{')) {
+			if ((status = __ntapi_tt_utf16_string_to_guid(
+					(nt_guid_str_utf16 *)&symlink[10],
+					&statfs->nt_volume_guid)))
 				return status;
 		}
 	}
 
-	return 0;
+	return NT_STATUS_SUCCESS;
 }