[pushed] libio: Disable vtable validation for pre-2.1 interposed handles [BZ #...

Message ID 20191127192010.417C020AF6@gnutoolchain-gerrit.osci.io
State Committed
Headers

Commit Message

Simon Marchi (Code Review) Nov. 27, 2019, 7:20 p.m. UTC
  Sourceware to Gerrit sync has submitted this change.

Change URL: https://gnutoolchain-gerrit.osci.io/r/c/glibc/+/699
......................................................................

libio: Disable vtable validation for pre-2.1 interposed handles [BZ #25203]

Commit c402355dfa7807b8e0adb27c009135a7e2b9f1b0 ("libio: Disable
vtable validation in case of interposition [BZ #23313]") only covered
the interposable glibc 2.1 handles, in libio/stdfiles.c.  The
parallel code in libio/oldstdfiles.c needs similar detection logic.

Fixes (again) commit db3476aff19b75c4fdefbe65fcd5f0a90588ba51
("libio: Implement vtable verification [BZ #20191]").

Change-Id: Ief6f9f17e91d1f7263421c56a7dc018f4f595c21
---
M libio/oldstdfiles.c
1 file changed, 5 insertions(+), 0 deletions(-)

Approvals:
  Carlos O'Donell: Looks good to me, approved
  

Patch

diff --git a/libio/oldstdfiles.c b/libio/oldstdfiles.c
index bb1705b..95c041a 100644
--- a/libio/oldstdfiles.c
+++ b/libio/oldstdfiles.c
@@ -83,6 +83,11 @@ 
 	= stderr->_vtable_offset =
 	((int) sizeof (struct _IO_FILE)
 	 - (int) sizeof (struct _IO_FILE_complete));
+
+      if (_IO_stdin_.vtable != &_IO_old_file_jumps
+	  || _IO_stdout_.vtable != &_IO_old_file_jumps
+	  || _IO_stderr_.vtable != &_IO_old_file_jumps)
+	IO_set_accept_foreign_vtables (&_IO_vtable_check);
     }
 }