From patchwork Fri Nov 23 05:08:44 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: virtio-scsi Fix some endian bugs with virtio-scsi Date: Thu, 22 Nov 2012 19:08:44 -0000 From: David Gibson X-Patchwork-Id: 201241 Message-Id: <1353647324-19840-1-git-send-email-david@gibson.dropbear.id.au> To: pbonzini@redhat.com, aliguori@us.ibm.com Cc: Paul 'Rusty' Russell , qemu-devel@nongnu.org, David Gibson The virtio-scsi specification does not specify the correct endianness for fields in the request structure. It's therefore best to assume that it is "guest native" endian since that's the (stupid and poorly defined) norm in virtio. However, the qemu device for virtio-scsi has no byteswaps at all, and so will break if the guest has different endianness from the host. This patch fixes it by adding tswap() calls for the sense_len and resid fields in the request structure. In theory status_qualifier needs swaps as well, but that field is never actually touched. The tag field is a uint64_t, but since its value is completely arbitrary, it might as well be uint8_t[8] and so it does not need swapping. Cc: Paolo Bonzini Cc: Paul 'Rusty' Russell Signed-off-by: David Gibson Reviewed-by: Stefan Hajnoczi --- hw/virtio-scsi.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/hw/virtio-scsi.c b/hw/virtio-scsi.c index 7d546f6..9d27d1d 100644 --- a/hw/virtio-scsi.c +++ b/hw/virtio-scsi.c @@ -428,11 +428,12 @@ static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status, req->resp.cmd->response = VIRTIO_SCSI_S_OK; req->resp.cmd->status = status; if (req->resp.cmd->status == GOOD) { - req->resp.cmd->resid = resid; + req->resp.cmd->resid = tswap32(resid); } else { req->resp.cmd->resid = 0; req->resp.cmd->sense_len = - scsi_req_get_sense(r, req->resp.cmd->sense, VIRTIO_SCSI_SENSE_SIZE); + tswap32(scsi_req_get_sense(r, req->resp.cmd->sense, + VIRTIO_SCSI_SENSE_SIZE)); } virtio_scsi_complete_req(req); }