1 files changed, 6 insertions, 5 deletions

diff --git a/src/firejail/join.c b/src/firejail/join.c
index 394bbb528..99fbfdd0a 100644
--- a/src/firejail/join.c
+++ b/src/firejail/join.c
@@ -45,7 +45,7 @@ static unsigned display = 0;
 static void signal_handler(int sig){
         flush_stdin();
 
-        exit(sig);
+        exit(128 + sig);
 }
 
 static void install_handler(void) {
@@ -536,7 +536,6 @@ void join(pid_t pid, int argc, char **argv, int index) {
                 prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
 
 #ifdef HAVE_APPARMOR
-                // add apparmor confinement after the execve
                 set_apparmor();
 #endif
 
@@ -596,15 +595,17 @@ void join(pid_t pid, int argc, char **argv, int index) {
 
         // end of signal-safe code
         //*****************************
-        flush_stdin();
 
         if (WIFEXITED(status)) {
+                // if we had a proper exit, return that exit status
                 status = WEXITSTATUS(status);
         } else if (WIFSIGNALED(status)) {
-                status = WTERMSIG(status);
+                // distinguish fatal signals by adding 128
+                status = 128 + WTERMSIG(status);
         } else {
-                status = 0;
+                status = -1;
         }
 
+        flush_stdin();
         exit(status);
 }