diff --git a/qrenderdoc/Windows/BufferViewer.cpp b/qrenderdoc/Windows/BufferViewer.cpp
index f70f1e640..d7c3b6728 100644
--- a/qrenderdoc/Windows/BufferViewer.cpp
+++ b/qrenderdoc/Windows/BufferViewer.cpp
@@ -2349,7 +2349,7 @@ void BufferViewer::configureMeshColumns()
 
       // drawing more than this many indices will read off the end of the index buffer - which while
       // technically not invalid is certainly not intended, so serves as a good 'upper bound'
-      numRowsUpperBound = bytesAvailable / draw->indexByteWidth;
+      numRowsUpperBound = bytesAvailable / qMax(1U, draw->indexByteWidth);
     }
     else
     {
diff --git a/renderdoc/driver/d3d12/d3d12_postvs.cpp b/renderdoc/driver/d3d12/d3d12_postvs.cpp
index 092114eb4..a524da085 100644
--- a/renderdoc/driver/d3d12/d3d12_postvs.cpp
+++ b/renderdoc/driver/d3d12/d3d12_postvs.cpp
@@ -371,8 +371,9 @@ void D3D12Replay::InitPostVSBuffers(uint32_t eventId)
     else    // drawcall is indexed
     {
       bytebuf idxdata;
-      GetBufferData(rs.ibuffer.buf, rs.ibuffer.offs + drawcall->indexOffset * rs.ibuffer.bytewidth,
-                    RDCMIN(drawcall->numIndices * rs.ibuffer.bytewidth, rs.ibuffer.size), idxdata);
+      if(rs.ibuffer.buf != ResourceId())
+        GetBufferData(rs.ibuffer.buf, rs.ibuffer.offs + drawcall->indexOffset * rs.ibuffer.bytewidth,
+                      RDCMIN(drawcall->numIndices * rs.ibuffer.bytewidth, rs.ibuffer.size), idxdata);
 
       vector<uint32_t> indices;
 
@@ -381,7 +382,7 @@ void D3D12Replay::InitPostVSBuffers(uint32_t eventId)
 
       // only read as many indices as were available in the buffer
       uint32_t numIndices =
-          RDCMIN(uint32_t(idxdata.size() / rs.ibuffer.bytewidth), drawcall->numIndices);
+          RDCMIN(uint32_t(idxdata.size() / RDCMAX(1, rs.ibuffer.bytewidth)), drawcall->numIndices);
 
       uint32_t idxclamp = 0;
       if(drawcall->baseVertex < 0)
diff --git a/renderdoc/driver/vulkan/vk_postvs.cpp b/renderdoc/driver/vulkan/vk_postvs.cpp
index b4efc8e68..7822e4097 100644
--- a/renderdoc/driver/vulkan/vk_postvs.cpp
+++ b/renderdoc/driver/vulkan/vk_postvs.cpp
@@ -1197,8 +1197,9 @@ void VulkanReplay::InitPostVSBuffers(uint32_t eventId)
     uint32_t *idx32 = NULL;
 
     // fetch ibuffer
-    GetBufferData(state.ibuffer.buf, state.ibuffer.offs + drawcall->indexOffset * idxsize,
-                  uint64_t(drawcall->numIndices) * idxsize, idxdata);
+    if(state.ibuffer.buf != ResourceId())
+      GetBufferData(state.ibuffer.buf, state.ibuffer.offs + drawcall->indexOffset * idxsize,
+                    uint64_t(drawcall->numIndices) * idxsize, idxdata);
 
     // figure out what the maximum index could be, so we can clamp our index buffer to something
     // sane
@@ -1463,7 +1464,8 @@ void VulkanReplay::InitPostVSBuffers(uint32_t eventId)
         offs += drawcall->vertexOffset * vi->pVertexBindingDescriptions[vb].stride;
       }
 
-      GetBufferData(state.vbuffers[vb].buf, offs, len, origVBs[vb]);
+      if(state.vbuffers[vb].buf != ResourceId())
+        GetBufferData(state.vbuffers[vb].buf, offs, len, origVBs[vb]);
     }
 
     for(uint32_t i = 0; i < vi->vertexAttributeDescriptionCount; i++)