Subject: Open Unix.LargeFile to avoid "lstat: Value too large for defined data type".
From: Richard W.M. Jones rjones@redhat.com Mon Feb 1 10:07:02 2021 +0000
Date: Mon Feb 1 10:22:45 2021 +0000:
Git: ea2935342326893257c74098e7df0835ee495b82

On 32 bit platforms, because OCaml native ints are limited to 31 bits,
there is a trap in the normal Unix.stat, Unix.lstat functions where
any field in the stat struct may overflow.  The result is random
errors like:

  supermin: error: lstat: Value too large for defined data type: /tmp/tmp.Ss9aYEBASm/d2/root

You would probably only see this on armv7.

The OCaml Unix module has a "LargeFile" submodule which fixes this by
using int64 for some (unfortunately not all) fields.

For more information see the OCaml sources, file
otherlibs/unix/stat.c, all instances of "EOVERFLOW".

(cherry picked from commit fd9f17c7eb63979af882533a0d234bfc8ca42de3)

diff --git a/src/format_chroot.ml b/src/format_chroot.ml
index 346c24b..34606f7 100644
--- a/src/format_chroot.ml
+++ b/src/format_chroot.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/format_ext2.ml b/src/format_ext2.ml
index 6348c29..e311ea6 100644
--- a/src/format_ext2.ml
+++ b/src/format_ext2.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/format_ext2_initrd.ml b/src/format_ext2_initrd.ml
index 38977e6..6268442 100644
--- a/src/format_ext2_initrd.ml
+++ b/src/format_ext2_initrd.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/format_ext2_kernel.ml b/src/format_ext2_kernel.ml
index 98bff3a..3be4413 100644
--- a/src/format_ext2_kernel.ml
+++ b/src/format_ext2_kernel.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
@@ -95,8 +96,8 @@ and find_kernel_from_lib_modules debug =
     let kernels =
       filter_map (
         fun kernel_file ->
-          let size = try (stat kernel_file).st_size with Unix_error _ -> 0 in
-          if size < 10000 then None
+          let size = try (stat kernel_file).st_size with Unix_error _ -> 0L in
+          if size < 10000_L then None
           else (
             let kernel_name = Filename.basename kernel_file in
             let modpath = Filename.dirname kernel_file in
diff --git a/src/mode_build.ml b/src/mode_build.ml
index ed47366..ff7733e 100644
--- a/src/mode_build.ml
+++ b/src/mode_build.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/package_handler.ml b/src/package_handler.ml
index 0409438..f0d6db3 100644
--- a/src/package_handler.ml
+++ b/src/package_handler.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/ph_dpkg.ml b/src/ph_dpkg.ml
index 1e785de..6d4fce1 100644
--- a/src/ph_dpkg.ml
+++ b/src/ph_dpkg.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/ph_pacman.ml b/src/ph_pacman.ml
index 67f7512..50500a5 100644
--- a/src/ph_pacman.ml
+++ b/src/ph_pacman.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/ph_rpm.ml b/src/ph_rpm.ml
index 9745efd..183b5f3 100644
--- a/src/ph_rpm.ml
+++ b/src/ph_rpm.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Utils
diff --git a/src/supermin.ml b/src/supermin.ml
index e923111..9f838d9 100644
--- a/src/supermin.ml
+++ b/src/supermin.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 open Types
diff --git a/src/utils.ml b/src/utils.ml
index b25df88..f5990ef 100644
--- a/src/utils.ml
+++ b/src/utils.ml
@@ -17,6 +17,7 @@
  *)
 
 open Unix
+open Unix.LargeFile
 open Printf
 
 let (+^) = Int64.add