From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 24 Jun 2024 10:52:57 +0000 (+0200)
Subject: stub: fix reporting of dtb measurement
X-Git-Tag: v257-rc1~1059^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F33461%2Fhead;p=thirdparty%2Fsystemd.git

stub: fix reporting of dtb measurement

Let's properly return the measurement flag tristate, rather than a
boolean. Otherwise we'll mistake "nothing to measure" as "not measured",
which are two different things, and means we'll miscombine the flag
later, claiming to userspace that we measured no dtb data even if there
was.
---

diff --git a/src/boot/efi/stub.c b/src/boot/efi/stub.c
index 8744d9821cb..f5d2b1d4c54 100644
--- a/src/boot/efi/stub.c
+++ b/src/boot/efi/stub.c
@@ -26,7 +26,7 @@ DECLARE_NOALLOC_SECTION(".sdmagic", "#### LoaderInfo: systemd-stub " GIT_VERSION
 
 DECLARE_SBAT(SBAT_STUB_SECTION_TEXT);
 
-static void combine_measured_flag(int *value, bool measured) {
+static void combine_measured_flag(int *value, int measured) {
         assert(value);
 
         /* Combine the "measured" flag in a sensible way: if we haven't measured anything yet, the first
@@ -39,6 +39,9 @@ static void combine_measured_flag(int *value, bool measured) {
          *    < 0 → nothing has been submitted for measurement so far
          */
 
+        if (measured < 0)
+                return;
+
         *value = *value < 0 ? measured : *value && measured;
 }
 
@@ -302,7 +305,7 @@ static void dtb_install_addons(
                 size_t *dt_sizes,
                 char16_t **dt_filenames,
                 size_t n_dts,
-                bool *ret_parameters_measured) {
+                int *ret_parameters_measured) {
 
         int parameters_measured = -1;
         EFI_STATUS err;
@@ -735,20 +738,22 @@ static EFI_STATUS run(EFI_HANDLE image) {
                         log_error_status(err, "Error loading embedded devicetree: %m");
         }
 
+        int dtb_measured;
         dtb_install_addons(&dt_state,
                            dt_bases_addons_global,
                            dt_sizes_addons_global,
                            dt_filenames_addons_global,
                            n_dts_addons_global,
-                           &m);
-        combine_measured_flag(&parameters_measured, m);
+                           &dtb_measured);
+        combine_measured_flag(&parameters_measured, dtb_measured);
+
         dtb_install_addons(&dt_state,
                            dt_bases_addons_uki,
                            dt_sizes_addons_uki,
                            dt_filenames_addons_uki,
                            n_dts_addons_uki,
-                           &m);
-        combine_measured_flag(&parameters_measured, m);
+                           &dtb_measured);
+        combine_measured_flag(&parameters_measured, dtb_measured);
 
         if (parameters_measured > 0)
                 (void) efivar_set_uint_string(MAKE_GUID_PTR(LOADER), u"StubPcrKernelParameters", TPM2_PCR_KERNEL_CONFIG, 0);