Re: [Qemu-devel] [PATCH] scsi: pvscsi: request descriptor data_length to 32 bit

[P J P <ppandit@redhat.com>]

+-- On Mon, 5 Sep 2016, Paolo Bonzini wrote --+
| Without a public spec it's hard, but I guess 2048 is more than enough.

===
diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c
index 4245c15..4823b9d 100644
--- a/hw/scsi/vmw_pvscsi.c
+++ b/hw/scsi/vmw_pvscsi.c
@@ -628,17 +628,16 @@ pvscsi_queue_pending_descriptor(PVSCSIState *s, SCSIDevice **d,
 static void
 pvscsi_convert_sglist(PVSCSIRequest *r)
 {
-    int chunk_size;
+    int chunk_size, n = 0;
     uint64_t data_length = r->req.dataLen;
     PVSCSISGState sg = r->sg;
-    while (data_length) {
-        while (!sg.resid) {
+    while (data_length && n < 2048) {
+        while (!sg.resid && n++ < 2048) {
             pvscsi_get_next_sg_elem(&sg);
             trace_pvscsi_convert_sglist(r->req.context, r->sg.dataAddr,
                                         r->sg.resid);
         }
-        assert(data_length > 0);
-        chunk_size = MIN((unsigned) data_length, sg.resid);
+        chunk_size = MIN(data_length, sg.resid);
         if (chunk_size) {
             qemu_sglist_add(&r->sgl, sg.dataAddr, chunk_size);
         }
===

Does this look okay?
--
Prasad J Pandit / Red Hat Product Security Team
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