svn commit: r317806 - head/sys/dev/nand

[Gleb Smirnoff]

Author: glebius
Date: Thu May  4 20:42:31 2017
New Revision: 317806
URL: https://svnweb.freebsd.org/changeset/base/317806

Log:
  The nandsim(4) simulator driver doesn't have any protection against
  races at least in its ioctl handler, and at the same time it creates
  device entry with 0666 permissions.
  
  To plug possible issues in it:
  - Mark it as needing Giant.
  - Switch device mode to 0600.
  
  Submitted by:	C Turt
  Reviewed by:	imp
  MFC after:	1 week
  Security:	Possible double free in ioctl handler

Modified:
  head/sys/dev/nand/nandsim.c

Modified: head/sys/dev/nand/nandsim.c
==============================================================================
--- head/sys/dev/nand/nandsim.c	Thu May  4 19:55:32 2017	(r317805)
+++ head/sys/dev/nand/nandsim.c	Thu May  4 20:42:31 2017	(r317806)
@@ -71,6 +71,7 @@ static struct nandsim_chip *get_nandsim_
 
 static struct cdevsw nandsim_cdevsw = {
 	.d_version =    D_VERSION,
+	.d_flags =	D_NEEDGIANT,
 	.d_ioctl =      nandsim_ioctl,
 	.d_name =       "nandsim",
 };
@@ -639,7 +640,7 @@ nandsim_modevent(module_t mod __unused, 
 	switch (type) {
 	case MOD_LOAD:
 		nandsim_dev = make_dev(&nandsim_cdevsw, 0,
-		    UID_ROOT, GID_WHEEL, 0666, "nandsim.ioctl");
+		    UID_ROOT, GID_WHEEL, 0600, "nandsim.ioctl");
 		break;
 	case MOD_UNLOAD:
 		for (i = 0; i < MAX_SIM_DEV; i++) {