diff --git a/src/libsystemd/sd-daemon/sd-daemon.c b/src/libsystemd/sd-daemon/sd-daemon.c index 437518119b..582fb53529 100644 --- a/src/libsystemd/sd-daemon/sd-daemon.c +++ b/src/libsystemd/sd-daemon/sd-daemon.c @@ -450,8 +450,10 @@ _public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char if (n_fds > 0 || have_pid) { /* CMSG_SPACE(0) may return value different then zero, which results in miscalculated controllen. */ - msghdr.msg_controllen = (n_fds ? CMSG_SPACE(sizeof(int) * n_fds) : 0) + - CMSG_SPACE(sizeof(struct ucred)) * have_pid; + msghdr.msg_controllen = + (n_fds > 0 ? CMSG_SPACE(sizeof(int) * n_fds) : 0) + + (have_pid ? CMSG_SPACE(sizeof(struct ucred)) : 0); + msghdr.msg_control = alloca(msghdr.msg_controllen); cmsg = CMSG_FIRSTHDR(&msghdr);