On Thu, May 24, 2018 at 12:25:23AM +0300, Michael S. Tsirkin wrote: > On Thu, Apr 12, 2018 at 11:12:29PM +0800, Tiwei Bie wrote: > > Signed-off-by: Tiwei Bie <tiwei....@intel.com> > > > Thinking about it, I think we should add a protocol > feature for this. This way remote can find out whether > it's safe to send this data to us.
Okay, I can add a protocol feature for this. Do you think it's OK to keep this patch as is (this patch just extends slave_read() to support receiving file descriptors) and introduce the new protocol feature in a new patch to allow backends to send file descriptors? Best regards, Tiwei Bie > > > --- > > hw/virtio/vhost-user.c | 41 ++++++++++++++++++++++++++++++++++++++++- > > 1 file changed, 40 insertions(+), 1 deletion(-) > > > > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > > index 91edd95453..9cea2c8c51 100644 > > --- a/hw/virtio/vhost-user.c > > +++ b/hw/virtio/vhost-user.c > > @@ -854,14 +854,44 @@ static void slave_read(void *opaque) > > VhostUserHeader hdr = { 0, }; > > VhostUserPayload payload = { 0, }; > > int size, ret = 0; > > + struct iovec iov; > > + struct msghdr msgh; > > + int fd = -1; > > + char control[CMSG_SPACE(sizeof(fd))]; > > + struct cmsghdr *cmsg; > > + size_t fdsize; > > + > > + memset(&msgh, 0, sizeof(msgh)); > > + msgh.msg_iov = &iov; > > + msgh.msg_iovlen = 1; > > + msgh.msg_control = control; > > + msgh.msg_controllen = sizeof(control); > > > > /* Read header */ > > - size = read(u->slave_fd, &hdr, VHOST_USER_HDR_SIZE); > > + iov.iov_base = &hdr; > > + iov.iov_len = VHOST_USER_HDR_SIZE; > > + > > + size = recvmsg(u->slave_fd, &msgh, 0); > > if (size != VHOST_USER_HDR_SIZE) { > > error_report("Failed to read from slave."); > > goto err; > > } > > > > + if (msgh.msg_flags & MSG_CTRUNC) { > > + error_report("Truncated message."); > > + goto err; > > + } > > + > > + for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL; > > + cmsg = CMSG_NXTHDR(&msgh, cmsg)) { > > + if (cmsg->cmsg_level == SOL_SOCKET && > > + cmsg->cmsg_type == SCM_RIGHTS) { > > + fdsize = cmsg->cmsg_len - CMSG_LEN(0); > > + memcpy(&fd, CMSG_DATA(cmsg), fdsize); > > + break; > > + } > > + } > > + > > if (hdr.size > VHOST_USER_PAYLOAD_SIZE) { > > error_report("Failed to read msg header." > > " Size %d exceeds the maximum %zu.", hdr.size, > > @@ -885,9 +915,15 @@ static void slave_read(void *opaque) > > break; > > default: > > error_report("Received unexpected msg type."); > > + if (fd != -1) { > > + close(fd); > > + } > > ret = -EINVAL; > > } > > > > + /* Message handlers need to make sure that fd will be consumed. */ > > + fd = -1; > > + > > /* > > * REPLY_ACK feature handling. Other reply types has to be managed > > * directly in their request handlers. > > @@ -920,6 +956,9 @@ err: > > qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL); > > close(u->slave_fd); > > u->slave_fd = -1; > > + if (fd != -1) { > > + close(fd); > > + } > > return; > > } > > > > -- > > 2.11.0 > > --------------------------------------------------------------------- > To unsubscribe, e-mail: virtio-dev-unsubscr...@lists.oasis-open.org > For additional commands, e-mail: virtio-dev-h...@lists.oasis-open.org > --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscr...@lists.oasis-open.org For additional commands, e-mail: virtio-dev-h...@lists.oasis-open.org