selinux: figure out selinux context applied on exec() before closing all fds

We need original socket_fd around otherwise mac_selinux_get_child_mls_label
fails with -EINVAL return code. Also don't call setexeccon twice but rather pass
context value of SELinuxContext option as an extra argument.

1 files changed, 2 insertions, 6 deletions

diff --git a/src/shared/selinux-util.c b/src/shared/selinux-util.c
index 6bd3bf1c80..a2233e0cfb 100644
--- a/src/shared/selinux-util.c
+++ b/src/shared/selinux-util.c
@@ -233,7 +233,7 @@ int mac_selinux_get_our_label(char **label) {
         return r;
 }
 
-int mac_selinux_get_child_mls_label(int socket_fd, const char *exe, char **label) {
+int mac_selinux_get_child_mls_label(int socket_fd, const char *exe, const char *exec_label, char **label) {
         int r = -EOPNOTSUPP;
 
 #ifdef HAVE_SELINUX
@@ -257,11 +257,7 @@ int mac_selinux_get_child_mls_label(int socket_fd, const char *exe, char **label
         if (r < 0)
                 return -errno;
 
-        r = getexeccon(&fcon);
-        if (r < 0)
-                return -errno;
-
-        if (!fcon) {
+        if (!exec_label) {
                 /* If there is no context set for next exec let's use context
                    of target executable */
                 r = getfilecon(exe, &fcon);