3 files changed, 7 insertions, 1 deletions

diff --git a/src/firejail/firejail.h b/src/firejail/firejail.h
index a364de75f..e4e6f4fa4 100644
--- a/src/firejail/firejail.h
+++ b/src/firejail/firejail.h
@@ -186,6 +186,7 @@ static inline int any_interface_configured(void) {
 
 extern int arg_private;         // mount private /home
 extern int arg_debug;           // print debug messages
+extern int arg_debug_check_filename;            // print debug messages for invalid_filename()
 extern int arg_nonetwork;       // --net=none
 extern int arg_command; // -c
 extern int arg_overlay;         // overlay option
diff --git a/src/firejail/main.c b/src/firejail/main.c
index 891653587..02eab1a86 100644
--- a/src/firejail/main.c
+++ b/src/firejail/main.c
@@ -50,6 +50,7 @@ static char child_stack[STACK_SIZE];		// space for child's stack
 Config cfg;                                     // configuration
 int arg_private = 0;                            // mount private /home and /tmp directoryu
 int arg_debug = 0;                              // print debug messages
+int arg_debug_check_filename;           // print debug messages for invalid_filename()
 int arg_nonetwork = 0;                          // --net=none
 int arg_command = 0;                            // -c
 int arg_overlay = 0;                            // overlay option
@@ -457,6 +458,10 @@ int main(int argc, char **argv) {
                 
                 if (strcmp(argv[i], "--debug") == 0)
                         arg_debug = 1;
+                else if (strcmp(argv[i], "--debug-check-filename") == 0) {
+                        arg_debug = 1;
+                        arg_debug_check_filename = 1;
+                }
                 else if (strcmp(argv[i], "--quiet") == 0)
                         arg_quiet = 1;
                 
diff --git a/src/firejail/util.c b/src/firejail/util.c
index 880e45465..0d9479a02 100644
--- a/src/firejail/util.c
+++ b/src/firejail/util.c
@@ -574,7 +574,7 @@ void invalid_filename(const char *fname) {
         assert(fname);
         const char *ptr = fname;
         
-        if (arg_debug)
+        if (arg_debug && arg_debug_check_filename)
                 printf("Checking filename %s\n", fname);
         
         if (strncmp(ptr, "${HOME}", 7) == 0)