validate region is segment

Signed-off-by: Thanos Makatos <thanos.makatos@nutanix.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/lib/dma.h b/lib/dma.h
index cd71e4e..e0d6d72 100644
--- a/lib/dma.h
+++ b/lib/dma.h
@@ -74,6 +74,7 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <limits.h>
+#include <errno.h>
 
 #include "libvfio-user.h"
 #include "common.h"
@@ -237,7 +238,14 @@ dma_map_sg(dma_controller_t *dma, const dma_sg_t *sg, struct iovec *iov,
     dma_memory_region_t *region;
     int i;
 
+    assert(dma != NULL);
+    assert(sg != NULL);
+    assert(iov != NULL);
+
     for (i = 0; i < cnt; i++) {
+        if (sg[i].region >= dma->nregions) {
+            return -EINVAL;
+        }
         vfu_log(dma->vfu_ctx, LOG_DEBUG, "map %#lx-%#lx\n",
                sg->dma_addr + sg->offset, sg->dma_addr + sg->offset + sg->length);
         region = &dma->regions[sg[i].region];