svn commit: r356251 - head/bin/sh

[Jilles Tjoelker]

Author: jilles
Date: Wed Jan  1 12:06:37 2020
New Revision: 356251
URL: https://svnweb.freebsd.org/changeset/base/356251

Log:
  sh: Fix rare memory leak with SIGINT
  
  If getcwd() failed earlier on but later succeeded in the pwd builtin,
  there was no INTOFF protection between calling savestr() and storing its
  result.
  
  It is quite rare for getcwd() to fail, and rarer for it to succeed later in
  the same directory.
  
  Found via code inspection for changing ckmalloc() and similar to assert
  INTOFF protection instead of applying it directly (which protects against
  corrupting malloc's internal state but allows memory leaks or double frees).
  
  MFC after:	1 week

Modified:
  head/bin/sh/cd.c

Modified: head/bin/sh/cd.c
==============================================================================
--- head/bin/sh/cd.c	Wed Jan  1 09:22:06 2020	(r356250)
+++ head/bin/sh/cd.c	Wed Jan  1 12:06:37 2020	(r356251)
@@ -376,8 +376,11 @@ getpwd(void)
 		return curdir;
 
 	p = getpwd2();
-	if (p != NULL)
+	if (p != NULL) {
+		INTOFF;
 		curdir = savestr(p);
+		INTON;
+	}
 
 	return curdir;
 }