From 00dc153637109b8d601c2bd705d68d0ecc920935 Mon Sep 17 00:00:00 2001
From: Koundinya Veluri <kouvel@microsoft.com>
Date: Tue, 8 Aug 2023 11:34:32 -0700
Subject: [PATCH] Restore a change to improve backward compatibility

---
 src/coreclr/pal/src/sharedmemory/sharedmemory.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/coreclr/pal/src/sharedmemory/sharedmemory.cpp b/src/coreclr/pal/src/sharedmemory/sharedmemory.cpp
index 9d7581788e9d6..a2342f23efa5c 100644
--- a/src/coreclr/pal/src/sharedmemory/sharedmemory.cpp
+++ b/src/coreclr/pal/src/sharedmemory/sharedmemory.cpp
@@ -188,7 +188,12 @@ bool SharedMemoryHelpers::EnsureDirectoryExists(
     }
     if (!createIfNotExist || chmod(path, PermissionsMask_AllUsers_ReadWriteExecute) != 0)
     {
-        throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
+        // We were not asked to create the path or we weren't able to set the new permissions.
+        // As a last resort, check that at least the current user has full access.
+        if ((statInfo.st_mode & PermissionsMask_CurrentUser_ReadWriteExecute) != PermissionsMask_CurrentUser_ReadWriteExecute)
+        {
+            throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
+        }
     }
     return true;
 }