src: zero-initialize cap_data in node_credentials.cc

zero-initialize the cap_data array to prevent
MSan warnings about using uninitialized memory

Signed-off-by: Sam Kapust <samkapust@google.com>
PR-URL: #64347
Reviewed-By: Jan Martin <jan.krems@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: spkapust

src/node_credentials.cc

@@ -50,7 +50,7 @@ namespace credentials {
 static bool HasOnly(int capability) {
   DCHECK(cap_valid(capability));
 
-  struct __user_cap_data_struct cap_data[_LINUX_CAPABILITY_U32S_3];
+  struct __user_cap_data_struct cap_data[_LINUX_CAPABILITY_U32S_3] = {};
   struct __user_cap_header_struct cap_header_data = {
     _LINUX_CAPABILITY_VERSION_3,
     getpid()};