From 2193d02b4ddfc329e0817258093a40050b2d582a Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Mon, 12 Dec 2005 10:00:32 +0000
Subject: [PATCH] 	* mmap.cc (gen_create_protect): Always generate
 WRITECOPY protection 	for private maps. 	(fixup_mmaps_after_fork): Fix
 calculation of WRITECOPY protection for 	VirtualProtect.  Add some
 words to the comment.

---
 winsup/cygwin/ChangeLog |  7 +++++++
 winsup/cygwin/mmap.cc   | 22 ++++++++++++----------
 2 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index dc8f92b72..af716dc92 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,10 @@
+2005-12-12  Corinna Vinschen  <corinna@vinschen.de>
+
+	* mmap.cc (gen_create_protect): Always generate WRITECOPY protection
+	for private maps.
+	(fixup_mmaps_after_fork): Fix calculation of WRITECOPY protection for
+	VirtualProtect.  Add some words to the comment.
+
 2005-12-10  Christopher Faylor  <cgf@timesys.com>
 
 	* dirent.h: Change the rest of the d_ino's to __deprecated_d_ino.
diff --git a/winsup/cygwin/mmap.cc b/winsup/cygwin/mmap.cc
index 2414668b5..ee6382c44 100644
--- a/winsup/cygwin/mmap.cc
+++ b/winsup/cygwin/mmap.cc
@@ -98,8 +98,10 @@ gen_create_protect (DWORD openflags, int flags)
 {
   DWORD ret = PAGE_READONLY;
 
-  if (openflags & GENERIC_WRITE)
-    ret = priv (flags) ? PAGE_WRITECOPY : PAGE_READWRITE;
+  if (priv (flags))
+    ret = PAGE_WRITECOPY;
+  else if (openflags & GENERIC_WRITE)
+    ret = PAGE_READWRITE;
 
   /* Ignore EXECUTE permission on 9x. */
   if ((openflags & GENERIC_EXECUTE)
@@ -1963,16 +1965,16 @@ fixup_mmaps_after_fork (HANDLE parent)
 				     "address %p, %E", address);
 		      return -1;
 		    }
-		  else if ((mbi.AllocationProtect & PAGE_WRITECOPY)
+		  else if ((mbi.AllocationProtect == PAGE_WRITECOPY
+			    || mbi.AllocationProtect == PAGE_EXECUTE_WRITECOPY)
 			   && (mbi.Protect == PAGE_READWRITE
 			       || mbi.Protect == PAGE_EXECUTE_READWRITE))
-		    {
-		      /* A PAGE_WRITECOPY page which has been written to is
-			 set to PAGE_READWRITE, but that's an incompatible
-			 protection to set the page to. */
-		      mbi.Protect &= ~PAGE_READWRITE;
-		      mbi.Protect |= PAGE_WRITECOPY;
-		    }
+		    /* A WRITECOPY page which has been written to is set to
+		       READWRITE, but that's an incompatible protection to
+		       set the page to.  Convert the protection to WRITECOPY
+		       so that the below VirtualProtect doesn't fail. */
+		    mbi.Protect <<= 1;
+
 		  if (!ReadProcessMemory (parent, address, address,
 					  mbi.RegionSize, NULL))
 		    {