[Libguestfs] [PATCH] daemon: selinux: Add setfiles -m option to suppress extra excludes (RHBZ#1433577).

[Richard W.M. Jones]

---
 daemon/selinux-relabel.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/daemon/selinux-relabel.c b/daemon/selinux-relabel.c
index 112bee1..2f48ee6 100644
--- a/daemon/selinux-relabel.c
+++ b/daemon/selinux-relabel.c
@@ -27,6 +27,8 @@
 #include "actions.h"
 #include "optgroups.h"
 
+#include "ignore-value.h"
+
 GUESTFSD_EXT_CMD(str_setfiles, setfiles);
 
 #define MAX_ARGS 64
@@ -37,6 +39,20 @@ optgroup_selinuxrelabel_available (void)
   return prog_exists (str_setfiles);
 }
 
+static int
+setfiles_has_m_option (void)
+{
+  static int flag = -1;
+  CLEANUP_FREE char *err = NULL;
+
+  if (flag == -1) {
+    ignore_value (command (NULL, &err, str_setfiles, "-m", NULL));
+    flag = err && strstr (err, /* "invalid option -- " */ "'m'") == NULL;
+  }
+
+  return flag;
+}
+
 /* Takes optional arguments, consult optargs_bitmask. */
 int
 do_selinux_relabel (const char *specfile, const char *path,
@@ -83,6 +99,13 @@ do_selinux_relabel (const char *specfile, const char *path,
   ADD_ARG (argv, i, "-e"); ADD_ARG (argv, i, s_selinux);
   ADD_ARG (argv, i, "-e"); ADD_ARG (argv, i, s_sys);
 
+  /* You have to use the -m option (where available) otherwise
+   * setfiles puts all the mountpoints on the excludes list for no
+   * useful reason (RHBZ#1433577).
+   */
+  if (setfiles_has_m_option ())
+    ADD_ARG (argv, i, "-m");
+
   /* Relabelling in a chroot. */
   if (STRNEQ (sysroot, "/")) {
     ADD_ARG (argv, i, "-r");
-- 
2.10.2