Re: [PATCH Hurd] Fix invalid port deallocation in `symlink'

[ludo at gnu dot org (Ludovic Courtès)]

Hi,

Samuel Thibault <samuel.thibault@gnu.org> skribis:

> Thanks!  symlinkat will need the same treatment.

Indeed.

Ludoâ.

2012-03-18  Ludovic CourtÃs  <ludo@gnu.org>

	* sysdeps/mach/hurd/symlink.c (__symlink): Deallocate NODE only
	when it is non-null.
	* sysdeps/mach/hurd/symlinkat.c (symlinkat): Likewise.

diff --git a/sysdeps/mach/hurd/symlink.c b/sysdeps/mach/hurd/symlink.c
index 857e236..4a4e61f 100644
--- a/sysdeps/mach/hurd/symlink.c
+++ b/sysdeps/mach/hurd/symlink.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 92, 93, 94, 95, 96, 97 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 12 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -44,6 +44,7 @@ __symlink (from, to)
     return -1;
 
   /* Create a new, unlinked node in the target directory.  */
+  node = MACH_PORT_NULL;
   err = __dir_mkfile (dir, O_WRITE, 0777 & ~_hurd_umask, &node);
 
   if (! err)
@@ -59,7 +60,9 @@ __symlink (from, to)
     err = __dir_link (dir, node, name, 1);
 
   __mach_port_deallocate (__mach_task_self (), dir);
-  __mach_port_deallocate (__mach_task_self (), node);
+
+  if (node != MACH_PORT_NULL)
+    __mach_port_deallocate (__mach_task_self (), node);
 
   if (err)
     return __hurd_fail (err);
diff --git a/sysdeps/mach/hurd/symlinkat.c b/sysdeps/mach/hurd/symlinkat.c
index 9a51c66..71806d7 100644
--- a/sysdeps/mach/hurd/symlinkat.c
+++ b/sysdeps/mach/hurd/symlinkat.c
@@ -1,5 +1,5 @@
 /* Create a symbolic link named relative to an open directory.  Hurd version.
-   Copyright (C) 1991,1992,1993,1994,1995,1996,1997,2006
+   Copyright (C) 1991,1992,1993,1994,1995,1996,1997,2006,2012
 	Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -51,6 +51,7 @@ symlinkat (from, fd, to)
     return -1;
 
   /* Create a new, unlinked node in the target directory.  */
+  node = MACH_PORT_NULL;
   err = __dir_mkfile (dir, O_WRITE, 0777 & ~_hurd_umask, &node);
 
   if (! err)
@@ -66,7 +67,9 @@ symlinkat (from, fd, to)
     err = __dir_link (dir, node, name, 1);
 
   __mach_port_deallocate (__mach_task_self (), dir);
-  __mach_port_deallocate (__mach_task_self (), node);
+
+  if (node != MACH_PORT_NULL)
+    __mach_port_deallocate (__mach_task_self (), node);
 
   if (err)
     return __hurd_fail (err);