[Libguestfs] [PATCH] Relax size checks for integer types

[Hilko Bengen]

I recenetly came across a Windows XP image, where one REG_QWORD value
(HKLM\Software\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Scripts\Shutdown\0\0\ExecTime)
would be displayed by hivexsh but hivex_value_qword() would return -1.

It turned out that the data length of this value was 16 bytes instead
of 8.

There is no problem in simply interpreting the first 4 (DWORD) or
8 (QWORD) bytes -- if there are enough bytes to be interpreted.
---
 lib/hivex.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/hivex.c b/lib/hivex.c
index a2bd43b..efc27f8 100644
--- a/lib/hivex.c
+++ b/lib/hivex.c
@@ -1624,7 +1624,7 @@ hivex_value_dword (hive_h *h, hive_value_h value)
   if (data == NULL)
     return -1;
 
-  if ((t != hive_t_dword && t != hive_t_dword_be) || len != 4) {
+  if ((t != hive_t_dword && t != hive_t_dword_be) || len < 4) {
     free (data);
     errno = EINVAL;
     return -1;
@@ -1650,7 +1650,7 @@ hivex_value_qword (hive_h *h, hive_value_h value)
   if (data == NULL)
     return -1;
 
-  if (t != hive_t_qword || len != 8) {
+  if (t != hive_t_qword || len < 8) {
     free (data);
     errno = EINVAL;
     return -1;
-- 
1.8.3.1