qga/commands-posix: qmp_guest_set_user_password: use ga_run_command helper

There's no need to check for the existence of the "chpasswd", "pw"
executables, as the exec() call will do that for us.

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Link: https://lore.kernel.org/r/20240320161648.158226-8-andrey.drobyshev@virtuozzo.com
Signed-off-by: Konstantin Kostiuk <kkostiuk@redhat.com>

qga/commands-posix.c

@@ -2151,14 +2151,8 @@ void qmp_guest_set_user_password(const char *username,
                                  Error **errp)
 {
     Error *local_err = NULL;
-    char *passwd_path = NULL;
-    pid_t pid;
-    int status;
-    int datafd[2] = { -1, -1 };
-    char *rawpasswddata = NULL;
+    g_autofree char *rawpasswddata = NULL;
     size_t rawpasswdlen;
-    char *chpasswddata = NULL;
-    size_t chpasswdlen;
 
     rawpasswddata = (char *)qbase64_decode(password, -1, &rawpasswdlen, errp);
     if (!rawpasswddata) {
@@ -2169,95 +2163,31 @@ void qmp_guest_set_user_password(const char *username,
 
     if (strchr(rawpasswddata, '\n')) {
         error_setg(errp, "forbidden characters in raw password");
-        goto out;
+        return;
     }
 
     if (strchr(username, '\n') ||
         strchr(username, ':')) {
         error_setg(errp, "forbidden characters in username");
-        goto out;
+        return;
     }
 
 #ifdef __FreeBSD__
-    chpasswddata = g_strdup(rawpasswddata);
-    passwd_path = g_find_program_in_path("pw");
+    g_autofree char *chpasswdata = g_strdup(rawpasswddata);
+    const char *crypt_flag = crypted ? "-H" : "-h";
+    const char *argv[] = {"pw", "usermod", "-n", username,
+                          crypt_flag, "0", NULL};
 #else
-    chpasswddata = g_strdup_printf("%s:%s\n", username, rawpasswddata);
-    passwd_path = g_find_program_in_path("chpasswd");
+    g_autofree char *chpasswddata = g_strdup_printf("%s:%s\n", username,
+                                                    rawpasswddata);
+    const char *crypt_flag = crypted ? "-e" : NULL;
+    const char *argv[] = {"chpasswd", crypt_flag, NULL};
 #endif
 
-    chpasswdlen = strlen(chpasswddata);
-
-    if (!passwd_path) {
-        error_setg(errp, "cannot find 'passwd' program in PATH");
-        goto out;
-    }
-
-    if (!g_unix_open_pipe(datafd, FD_CLOEXEC, NULL)) {
-        error_setg(errp, "cannot create pipe FDs");
-        goto out;
-    }
-
-    pid = fork();
-    if (pid == 0) {
-        close(datafd[1]);
-        /* child */
-        setsid();
-        dup2(datafd[0], 0);
-        reopen_fd_to_null(1);
-        reopen_fd_to_null(2);
-
-#ifdef __FreeBSD__
-        const char *h_arg;
-        h_arg = (crypted) ? "-H" : "-h";
-        execl(passwd_path, "pw", "usermod", "-n", username, h_arg, "0", NULL);
-#else
-        if (crypted) {
-            execl(passwd_path, "chpasswd", "-e", NULL);
-        } else {
-            execl(passwd_path, "chpasswd", NULL);
-        }
-#endif
-        _exit(EXIT_FAILURE);
-    } else if (pid < 0) {
-        error_setg_errno(errp, errno, "failed to create child process");
-        goto out;
-    }
-    close(datafd[0]);
-    datafd[0] = -1;
-
-    if (qemu_write_full(datafd[1], chpasswddata, chpasswdlen) != chpasswdlen) {
-        error_setg_errno(errp, errno, "cannot write new account password");
-        goto out;
-    }
-    close(datafd[1]);
-    datafd[1] = -1;
-
-    ga_wait_child(pid, &status, &local_err);
+    ga_run_command(argv, chpasswddata, "set user password", &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
-        goto out;
-    }
-
-    if (!WIFEXITED(status)) {
-        error_setg(errp, "child process has terminated abnormally");
-        goto out;
-    }
-
-    if (WEXITSTATUS(status)) {
-        error_setg(errp, "child process has failed to set user password");
-        goto out;
-    }
-
-out:
-    g_free(chpasswddata);
-    g_free(rawpasswddata);
-    g_free(passwd_path);
-    if (datafd[0] != -1) {
-        close(datafd[0]);
-    }
-    if (datafd[1] != -1) {
-        close(datafd[1]);
+        return;
     }
 }
 #else /* __linux__ || __FreeBSD__ */