https://bugs.gentoo.org/show_bug.cgi?id=450536
Patch by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>

Probe the preferred version
--- vsftpd-3.0.2/sysdeputil.c.org       2013-01-05 18:32:13.241288839 +0100
+++ vsftpd-3.0.2/sysdeputil.c   2013-01-05 19:41:53.038148078 +0100
@@ -561,11 +561,17 @@
 }

   #ifndef VSF_SYSDEP_HAVE_LIBCAP
+static struct __user_cap_header_struct sys_cap_head;
 static int
 do_checkcap(void)
 {
+  int retval;
+
+  /* Store preferred version in sys_cap_head */
+  vsf_sysutil_memclr(&sys_cap_head, sizeof(sys_cap_head));
   /* EFAULT (EINVAL if page 0 mapped) vs. ENOSYS */
-  int retval = capset(0, 0);
+  retval = capset(&sys_cap_head, 0);
+
   if (!vsf_sysutil_retval_is_error(retval) ||
       vsf_sysutil_get_error() != kVSFSysUtilErrNOSYS)
   {
@@ -579,17 +585,13 @@
 {
   /* n.b. yes I know I should be using libcap!! */
   int retval;
-  struct __user_cap_header_struct cap_head;
-  struct __user_cap_data_struct cap_data;
+  struct __user_cap_data_struct cap_data[2];
   __u32 cap_mask = 0;
   if (!caps)
   {
     bug("asked to adopt no capabilities");
   }
-  vsf_sysutil_memclr(&cap_head, sizeof(cap_head));
   vsf_sysutil_memclr(&cap_data, sizeof(cap_data));
-  cap_head.version = _LINUX_CAPABILITY_VERSION;
-  cap_head.pid = 0;
   if (caps & kCapabilityCAP_CHOWN)
   {
     cap_mask |= (1 << CAP_CHOWN);
@@ -598,9 +600,9 @@
   {
     cap_mask |= (1 << CAP_NET_BIND_SERVICE);
   }
-  cap_data.effective = cap_data.permitted = cap_mask;
-  cap_data.inheritable = 0;
-  retval = capset(&cap_head, &cap_data);
+  cap_data[0].effective = cap_data[0].permitted = cap_mask;
+  cap_data[0].inheritable = 0;
+  retval = capset(&sys_cap_head, &cap_data[0]);
   if (retval != 0)
   {
     die("capset");