Re: libio compat fixes

[Daniel Jacobowitz <drow at mvista dot com>]

[Ooops, diffed the wrong tree; here it is without re-introducing a
typo.]

There's a comment in _IO_old_file_init that says that all _IO_FILE_plus's
(other than the three standard streams) are dynamically allocated and have
enough room for _mode.  Unfortunately, they are dynamically allocated but do
_not_ have enough room for mode.  They're allocated as:
  struct LOCKED_file {
    struct _IO_FILE_plus fp;
    lock;
  };
and _IO_FILE_plus changes based on whether we're compiling compatibility
code or not.

This patch adds an _IO_FILE_complete_plus which is big enough.  This
prevents some out-of-bounds scribbling that was causing an old compiled
binary to crash for me.

It also calls _IO_old_init from _IO_old_popen instead of _IO_init.  When
fopen and fdopen were changed in May this one slipped through.

Look OK?

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

2003-10-27  Daniel Jacobowitz  <drow@mvista.com>

	* libio/libioP.h [_IO_USE_OLD_IO_FILE]
	(struct _IO_FILE_complete_plus): New type.
	* libio/oldiofopen.c (_IO_old_fopen): Use _IO_FILE_complete_plus.
	* libio/oldiofdopen.c (_IO_old_fdopen): Likewise.
	* libio/oldiopopen.c (struct _IO_proc_file, _IO_old_popen): Likewise.
	Call _IO_old_init instead of _IO_init.

--- glibc-2.3.2/libio/libioP.h.orig	2003-10-27 15:48:39.000000000 -0500
+++ glibc-2.3.2/libio/libioP.h	2003-10-27 16:04:03.000000000 -0500
@@ -348,6 +348,17 @@ struct _IO_FILE_plus
   const struct _IO_jump_t *vtable;
 };
 
+#ifdef _IO_USE_OLD_IO_FILE
+/* This structure is used by the compatibility code as if it were an
+   _IO_FILE_plus, but has enough space to initialize the _mode argument
+   of an _IO_FILE_complete.  */
+struct _IO_FILE_complete_plus
+{
+  struct _IO_FILE_complete file;
+  const struct _IO_jump_t *vtable;
+};
+#endif
+
 /* Special file type for fopencookie function.  */
 struct _IO_cookie_file
 {
--- glibc-2.3.2/libio/oldiofdopen.c.orig	2003-10-27 15:57:58.000000000 -0500
+++ glibc-2.3.2/libio/oldiofdopen.c	2003-10-27 16:11:28.000000000 -0500
@@ -48,7 +48,7 @@ _IO_old_fdopen (fd, mode)
   int posix_mode = 0;
   struct locked_FILE
   {
-    struct _IO_FILE_plus fp;
+    struct _IO_FILE_complete_plus fp;
 #ifdef _IO_MTSAFE_IO
     _IO_lock_t lock;
 #endif
@@ -112,24 +112,24 @@ _IO_old_fdopen (fd, mode)
   if (new_f == NULL)
     return NULL;
 #ifdef _IO_MTSAFE_IO
-  new_f->fp.file._lock = &new_f->lock;
+  new_f->fp.file._file._lock = &new_f->lock;
 #endif
-  _IO_old_init (&new_f->fp.file, 0);
-  _IO_JUMPS (&new_f->fp) = &_IO_old_file_jumps;
-  _IO_old_file_init (&new_f->fp);
+  _IO_old_init (&new_f->fp.file._file, 0);
+  _IO_JUMPS ((struct _IO_FILE_plus *) &new_f->fp) = &_IO_old_file_jumps;
+  _IO_old_file_init ((struct _IO_FILE_plus *) &new_f->fp);
 #if  !_IO_UNIFIED_JUMPTABLES
   new_f->fp.vtable = NULL;
 #endif
-  if (_IO_old_file_attach (&new_f->fp.file, fd) == NULL)
+  if (_IO_old_file_attach (&new_f->fp.file._file, fd) == NULL)
     {
-      INTUSE(_IO_un_link) (&new_f->fp);
+      INTUSE(_IO_un_link) ((struct _IO_FILE_plus *) &new_f->fp);
       free (new_f);
       return NULL;
     }
-  new_f->fp.file._flags &= ~_IO_DELETE_DONT_CLOSE;
+  new_f->fp.file._file._flags &= ~_IO_DELETE_DONT_CLOSE;
 
-  new_f->fp.file._IO_file_flags =
-    _IO_mask_flags (&new_f->fp.file, read_write,
+  new_f->fp.file._file._IO_file_flags =
+    _IO_mask_flags (&new_f->fp.file._file, read_write,
 		    _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
 
   return (_IO_FILE *) &new_f->fp;
--- glibc-2.3.2/libio/oldiofopen.c.orig	2003-10-27 15:57:55.000000000 -0500
+++ glibc-2.3.2/libio/oldiofopen.c	2003-10-27 16:11:26.000000000 -0500
@@ -42,7 +42,7 @@ _IO_old_fopen (filename, mode)
 {
   struct locked_FILE
   {
-    struct _IO_FILE_plus fp;
+    struct _IO_FILE_complete_plus fp;
 #ifdef _IO_MTSAFE_IO
     _IO_lock_t lock;
 #endif
@@ -51,17 +51,17 @@ _IO_old_fopen (filename, mode)
   if (new_f == NULL)
     return NULL;
 #ifdef _IO_MTSAFE_IO
-  new_f->fp.file._lock = &new_f->lock;
+  new_f->fp.file._file._lock = &new_f->lock;
 #endif
-  _IO_old_init (&new_f->fp.file, 0);
-  _IO_JUMPS (&new_f->fp) = &_IO_old_file_jumps;
-  _IO_old_file_init (&new_f->fp);
+  _IO_old_init (&new_f->fp.file._file, 0);
+  _IO_JUMPS ((struct _IO_FILE_plus *) &new_f->fp) = &_IO_old_file_jumps;
+  _IO_old_file_init ((struct _IO_FILE_plus *) &new_f->fp);
 #if  !_IO_UNIFIED_JUMPTABLES
   new_f->fp.vtable = NULL;
 #endif
   if (_IO_old_file_fopen ((_IO_FILE *) &new_f->fp, filename, mode) != NULL)
     return (_IO_FILE *) &new_f->fp;
-  INTUSE(_IO_un_link) (&new_f->fp);
+  INTUSE(_IO_un_link) ((struct _IO_FILE_plus *) &new_f->fp);
   free (new_f);
   return NULL;
 }
--- glibc-2.3.2/libio/oldiopopen.c.orig	2003-10-27 14:11:13.000000000 -0500
+++ glibc-2.3.2/libio/oldiopopen.c	2003-10-27 16:24:10.000000000 -0500
@@ -100,7 +100,7 @@ extern int _IO_dup2 __P ((int fd, int fd
 
 struct _IO_proc_file
 {
-  struct _IO_FILE_plus file;
+  struct _IO_FILE_complete_plus file;
   /* Following fields must match those in class procbuf (procbuf.h) */
   _IO_pid_t pid;
   struct _IO_proc_file *next;
@@ -219,18 +219,18 @@ _IO_old_popen (command, mode)
   if (new_f == NULL)
     return NULL;
 #ifdef _IO_MTSAFE_IO
-  new_f->fpx.file.file._lock = &new_f->lock;
+  new_f->fpx.file.file._file._lock = &new_f->lock;
 #endif
-  fp = &new_f->fpx.file.file;
-  INTUSE(_IO_init) (fp, 0);
-  _IO_JUMPS (&new_f->fpx.file) = &_IO_old_proc_jumps;
-  _IO_old_file_init (&new_f->fpx.file);
+  fp = &new_f->fpx.file.file._file;
+  _IO_old_init (fp, 0);
+  _IO_JUMPS ((struct _IO_FILE_plus *) &new_f->fpx.file) = &_IO_old_proc_jumps;
+  _IO_old_file_init ((struct _IO_FILE_plus *) &new_f->fpx.file);
 #if  !_IO_UNIFIED_JUMPTABLES
   new_f->fpx.file.vtable = NULL;
 #endif
   if (_IO_old_proc_open (fp, command, mode) != NULL)
     return fp;
-  INTUSE(_IO_un_link) (&new_f->fpx.file);
+  INTUSE(_IO_un_link) ((struct _IO_FILE_plus *) &new_f->fpx.file);
   free (new_f);
   return NULL;
 }