svn commit: r332063 - stable/10/sys/compat/linux

[Ed Maste]

Author: emaste
Date: Thu Apr  5 12:50:47 2018
New Revision: 332063
URL: https://svnweb.freebsd.org/changeset/base/332063

Log:
  MFC r332034: linux_ioctl_hdio: fix kernel memory disclosure
  
  Stack-allocated struct linux_hd_big_geometry has undeclared padding
  copied to userland.
  
  admbugs:	765
  Reported by:	Vlad Tsyrklevich
  Security:	Kernel memory disclosure
  Sponsored by:	The FreeBSD Foundation

Modified:
  stable/10/sys/compat/linux/linux_ioctl.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/compat/linux/linux_ioctl.c
==============================================================================
--- stable/10/sys/compat/linux/linux_ioctl.c	Thu Apr  5 12:48:58 2018	(r332062)
+++ stable/10/sys/compat/linux/linux_ioctl.c	Thu Apr  5 12:50:47 2018	(r332063)
@@ -246,6 +246,7 @@ linux_ioctl_hdio(struct thread *td, struct linux_ioctl
 		} else if ((args->cmd & 0xffff) == LINUX_HDIO_GET_GEO_BIG) {
 			struct linux_hd_big_geometry hdbg;
 
+			memset(&hdbg, 0, sizeof(hdbg));
 			hdbg.cylinders = fwcylinders;
 			hdbg.heads = fwheads;
 			hdbg.sectors = fwsectors;