* unix/tclUnixPipe.c (TclpCreateProcess): for USE_VFORK: ensure standard

    channels are initialized before vfork() so that the child doesn't
    potentially corrupt global state in the parent's address space.

2 files changed, 36 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 2846f73..6100c06 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,10 +1,26 @@
+2006-08-03  Daniel Steffen  <das@users.sourceforge.net>
+
+	* unix/tclUnixPipe.c (TclpCreateProcess): for USE_VFORK: ensure standard
+	channels are initialized before vfork() so that the child doesn't
+	potentially corrupt global state in the parent's address space.
+
+	* tests/compExpr-old.test: add 'oldExprParser' constraint to all tests
+	* tests/compExpr.test:     that depend on the exact format of the error
+	* tests/compile.test:      messages of the pre-2006-07-05 expression
+	* tests/expr-old.test:     parser. The constraint is on by default (i.e.
+	* tests/expr.test:         those test still fail), but it can be turned
+	* tests/for.test:          off by passing '-constraints newExprParser'
+	* tests/if.test:           to tcltest, which will skip the 196 failing
+	* tests/parseExpr.test:    tests in the testsuite that are caused by
+	* tests/while.test:        the new expression parser error messages.
+
 2006-07-31  Kevin Kenny  <kennykb@acm.org>
 
 	* generic/tclClock.c (ConvertLocalToUTCUsingC):
 	Corrected a regression that caused dates before 1969 to be
 	one day off in the :localtime time zone if TZ is not set.
 	[Bug 1531530]
-	
+
 2006-07-30  Kevin Kenny  <kennykb@acm.org>
 
 	* generic/tclClock.c (GetJulianDayFromEraYearMonthDay):
@@ -44,7 +60,7 @@
 	* generic/tclExecute.c:
 	* tests/execute.test (execute-9.1): dgp's fix for [Bug 1522803].
 
-2006-07-20   Daniel Steffen  <das@users.sourceforge.net>
+2006-07-20  Daniel Steffen  <das@users.sourceforge.net>
 
 	* macosx/tclMacOSXNotify.c (Tcl_InitNotifier, Tcl_WaitForEvent): create
 	notifier thread lazily upon first call to Tcl_WaitForEvent() rather than
diff --git a/unix/tclUnixPipe.c b/unix/tclUnixPipe.c
index 8a20bcc..c177f67 100644
--- a/unix/tclUnixPipe.c
+++ b/unix/tclUnixPipe.c
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclUnixPipe.c,v 1.34 2006/07/20 06:17:39 das Exp $
+ * RCS: @(#) $Id: tclUnixPipe.c,v 1.35 2006/08/02 20:04:11 das Exp $
  */
 
 #include "tclInt.h"
@@ -428,6 +428,23 @@ TclpCreateProcess(
 	newArgv[i] = Tcl_UtfToExternalDString(NULL, argv[i], -1, &dsArray[i]);
     }
 
+#ifdef USE_VFORK
+    /*
+     * After vfork(), do not call code in the child that changes global state,
+     * because it is using the parent's memory space at that point and writes
+     * might corrupt the parent: so ensure standard channels are initialized in
+     * the parent, otherwise SetupStdFile() might initialize them in the child.
+     */
+    if (!inputFile) {
+	Tcl_GetStdChannel(TCL_STDIN);
+    }
+    if (!outputFile) {
+        Tcl_GetStdChannel(TCL_STDOUT);
+    }
+    if (!errorFile) {
+        Tcl_GetStdChannel(TCL_STDERR);
+    }
+#endif
     pid = fork();
     if (pid == 0) {
 	int joinThisError = errorFile && (errorFile == outputFile);