svn commit: r331749 - stable/10/sys/compat/svr4

[Ed Maste]

Author: emaste
Date: Thu Mar 29 22:31:14 2018
New Revision: 331749
URL: https://svnweb.freebsd.org/changeset/base/331749

Log:
  MF11 r331330: Fix kernel memory disclosure in svr4_sys_getdents64
  
  svr4_sys_getdents64() copies a dirent structure to userland.  When
  calculating the record length for any given dirent entry alignment is
  performed.  However, the aligned bytes are not cleared, this will
  trigger an info leak.
  
  Reported by:	Ilja Van Sprundel <ivansprundel at ioactive.com>
  Security:	Kernel memory disclosure (801)
  Sponsored by:	The FreeBSD Foundation

Modified:
  stable/10/sys/compat/svr4/svr4_misc.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/compat/svr4/svr4_misc.c
==============================================================================
--- stable/10/sys/compat/svr4/svr4_misc.c	Thu Mar 29 20:39:05 2018	(r331748)
+++ stable/10/sys/compat/svr4/svr4_misc.c	Thu Mar 29 22:31:14 2018	(r331749)
@@ -260,6 +260,7 @@ svr4_sys_getdents64(td, uap)
 	u_long *cookies = NULL, *cookiep;
 	int ncookies;
 
+	memset(&svr4_dirent, 0, sizeof(svr4_dirent));
 	DPRINTF(("svr4_sys_getdents64(%d, *, %d)\n",
 		uap->fd, uap->nbytes));
 	error = getvnode(td->td_proc->p_fd, uap->fd,