On 07/23/2012 07:08 AM, Corey Bryant wrote:
Set the close-on-exec flag for the file descriptor received via SCM_RIGHTS.
+++ b/qemu-char.c @@ -2263,9 +2263,17 @@ static ssize_t tcp_chr_recv(CharDriverState *chr, char *buf, size_t len) msg.msg_control = &msg_control; msg.msg_controllen = sizeof(msg_control);
+#ifdef MSG_CMSG_CLOEXEC + ret = recvmsg(s->fd, &msg, MSG_CMSG_CLOEXEC); +#else ret = recvmsg(s->fd, &msg, 0); - if (ret > 0 && s->is_unix) + if (ret > 0) { + qemu_set_cloexec(s->fd);
Wrong fd. You aren't changing cloexec on the socket (s->fd), but on the fd that was received via msg (which you don't know at this point in time).
+ } +#endif + if (ret > 0 && s->is_unix) { unix_process_msgfd(chr, &msg);
Only here do you know what fd you received. I would write it more like: int flags = 0; #ifdef MSG_CMSG_CLOEXEC flags |= MSG_CMSG_CLOEXEC #endif ret = recvmsg(s->fd, &msg, flags); if (ret > 0 && s->is_unix) { unix_process_msgfd(chr, &msg); #ifndef MSG_CMSG_CLOEXEC qemu_set_cloexec(/* fd determined from msg */) #endif } which almost implies that unix_process_msgfd() should be the function that sets cloexec, but without wasting the time doing so if recvmsg already did the job. -- Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org