diff --git a/pkgs/by-name/tb/tboot/package.nix b/pkgs/by-name/tb/tboot/package.nix
index a553c9d7ca7d..f26ab8c154a0 100644
--- a/pkgs/by-name/tb/tboot/package.nix
+++ b/pkgs/by-name/tb/tboot/package.nix
@@ -14,7 +14,7 @@ stdenv.mkDerivation rec {
 
   src = fetchurl {
     url = "mirror://sourceforge/tboot/${pname}-${version}.tar.gz";
-    sha256 = "sha256-TIs/xLxLBkKBN0a0CRB2KMmCq8QgICH1++i485WDU3A=";
+    hash = "sha256-TIs/xLxLBkKBN0a0CRB2KMmCq8QgICH1++i485WDU3A=";
   };
 
   buildInputs = [
@@ -34,14 +34,21 @@ stdenv.mkDerivation rec {
     substituteInPlace docs/Makefile --replace /usr/share /share
   '';
 
+  postPatch = ''
+    # compute the allocated size from the pointed type, to avoid the warning
+    substituteInPlace lcptools-v2/pconf_legacy.c \
+      --replace-fail "digest = malloc(SHA1_DIGEST_SIZE);" \
+        "digest = malloc(sizeof *digest);"
+  '';
+
   installFlags = [ "DESTDIR=$(out)" ];
 
-  meta = with lib; {
+  meta = {
     description = "Pre-kernel/VMM module that uses Intel(R) TXT to perform a measured and verified launch of an OS kernel/VMM";
     homepage = "https://sourceforge.net/projects/tboot/";
     changelog = "https://sourceforge.net/p/tboot/code/ci/v${version}/tree/CHANGELOG";
-    license = licenses.bsd3;
-    maintainers = with maintainers; [ ak ];
+    license = lib.licenses.bsd3;
+    maintainers = with lib.maintainers; [ ak ];
     platforms = [
       "x86_64-linux"
       "i686-linux"