1 files changed, 19 insertions, 4 deletions

diff --git a/src/firejail/join.c b/src/firejail/join.c
index acd17366a..35e302bf0 100644
--- a/src/firejail/join.c
+++ b/src/firejail/join.c
@@ -306,10 +306,25 @@ void join(pid_t pid, const char *homedir, int argc, char **argv, int index) {
                 if (setenv("PROMPT_COMMAND", "export PS1=\"\\[\\e[1;32m\\][\\u@\\h \\W]\\$\\[\\e[0m\\] \"", 1) < 0)
                         errExit("setenv");
 
-                // run icmdline trough /bin/bash
-                if (cfg.command_line == NULL)
-                        // replace the process with a regular bash session
-                        execlp("/bin/bash", "/bin/bash", NULL);
+                // run cmdline trough /bin/bash
+                if (cfg.command_line == NULL) {
+                        struct stat s;
+
+                        // replace the process with a shell
+                        if (stat("/bin/bash", &s) == 0)
+                                execlp("/bin/bash", "/bin/bash", NULL);
+                        else if (stat("/usr/bin/zsh", &s) == 0)
+                                execlp("/usr/bin/zsh", "/usr/bin/zsh", NULL);
+                        else if (stat("/bin/csh", &s) == 0)
+                                execlp("/bin/csh", "/bin/csh", NULL);
+                        else if (stat("/bin/sh", &s) == 0)
+                                execlp("/bin/sh", "/bin/sh", NULL);
+                        
+                        // no shell found, print an error and exit
+                        fprintf(stderr, "Error: no POSIX shell found\n");
+                        sleep(5);
+                        exit(1);
+                }
                 else {
                         // run the command supplied by the user
                         int cwd = 0;