diff --git a/fs_mgr/liblp/builder.cpp b/fs_mgr/liblp/builder.cpp
index 2015e4d..018c280 100644
--- a/fs_mgr/liblp/builder.cpp
+++ b/fs_mgr/liblp/builder.cpp
@@ -386,6 +386,7 @@
     }
 
     const uint64_t sectors_per_block = device_info_.logical_block_size / LP_SECTOR_SIZE;
+    CHECK_NE(sectors_per_block, 0);
     CHECK(sectors_needed % sectors_per_block == 0);
 
     // Find gaps that we can use for new extents. Note we store new extents in a