dotnet8.0/runtime-apphost-compare-noopt.patch
Tom Deseyn 8b64e99a86 Update to .NET SDK 8.0.128 and Runtime 8.0.28
Resolves: RHEL-181053
2026-06-16 16:24:24 +02:00

47 lines
2.0 KiB
Diff

From: Tom Deseyn <tdeseyn@redhat.com>
Subject: [PATCH] Avoid compiler optimization on embedded apphost hash
Backport of https://github.com/dotnet/runtime/pull/110554 to .NET 8.0.
---
src/runtime/src/native/corehost/corehost.cpp | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)
--- a/src/runtime/src/native/corehost/corehost.cpp
+++ b/src/runtime/src/native/corehost/corehost.cpp
@@ -40,6 +40,19 @@
#define EMBED_HASH_LO_PART_UTF8 "74e592c2fa383d4a3960714caef0c4f2"
#define EMBED_HASH_FULL_UTF8 (EMBED_HASH_HI_PART_UTF8 EMBED_HASH_LO_PART_UTF8) // NUL terminated
+// This avoids compiler optimization which cause EMBED_HASH_HI_PART_UTF8 EMBED_HASH_LO_PART_UTF8
+// to be placed adjacent causing them to match EMBED_HASH_FULL_UTF8 when searched for replacing.
+// See https://github.com/dotnet/runtime/issues/109611 for more details.
+static bool compare_memory_nooptimization(volatile const char* a, volatile const char* b, size_t length)
+{
+ for (size_t i = 0; i < length; i++)
+ {
+ if (*a++ != *b++)
+ return false;
+ }
+ return true;
+}
+
bool is_exe_enabled_for_execution(pal::string_t* app_dll)
{
constexpr int EMBED_SZ = sizeof(EMBED_HASH_FULL_UTF8) / sizeof(EMBED_HASH_FULL_UTF8[0]);
@@ -63,11 +76,10 @@
// So use two parts of the string that will be unaffected by the edit.
size_t hi_len = (sizeof(hi_part) / sizeof(hi_part[0])) - 1;
size_t lo_len = (sizeof(lo_part) / sizeof(lo_part[0])) - 1;
-
- std::string binding(&embed[0]);
- if ((binding.size() >= (hi_len + lo_len)) &&
- binding.compare(0, hi_len, &hi_part[0]) == 0 &&
- binding.compare(hi_len, lo_len, &lo_part[0]) == 0)
+ size_t embed_len = strlen(&embed[0]);
+ if (embed_len >= (hi_len + lo_len)
+ && compare_memory_nooptimization(&embed[0], hi_part, hi_len)
+ && compare_memory_nooptimization(&embed[hi_len], lo_part, lo_len))
{
trace::error(_X("This executable is not bound to a managed DLL to execute. The binding value is: '%s'"), app_dll->c_str());
return false;