Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Martin Schwidefsky:
 "Pretty boring for a merge window pull.

  One change in behaviour is the patch for dasd driver, the module which
  provides the diagnose discipline is now loaded automatically.

  The SCLP code got a nice cleanup, a new global structure replaces a
  bunch of accessor functions.

  And a couple of random, small improvements"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pci: improve handling of hotplug event 0x301
  s390/setup: fix DMA_API_DEBUG warnings
  s390/zcrypt: remove obsolete __constant
  s390/keyboard: avoid off-by-one when using strnlen_user()
  s390/sclp: pass timeout as HZ independent value
  s390/mm: s/specifiation/specification/, s/an specification/a specification/
  s390/sclp: Use DECLARE_BITMAP
  s390/dasd: Enable automatic loading of dasd_diag_mod
  s390/sclp: move sclp_facilities into "struct sclp"
  s390/sclp: get rid of sclp_get_mtid() and sclp_get_mtid_max()
  s390/sclp: unify basic sclp access by exposing "struct sclp"
  s390/sclp: prepare smp_fill_possible_mask for global "struct sclp"

1 files changed, 8 insertions, 5 deletions

diff --git a/drivers/s390/char/keyboard.c b/drivers/s390/char/keyboard.c
index 01463b052ae7..ef04a9f7a704 100644
--- a/drivers/s390/char/keyboard.c
+++ b/drivers/s390/char/keyboard.c
@@ -433,20 +433,23 @@ do_kdgkb_ioctl(struct kbd_data *kbd, struct kbsentry __user *u_kbs,
 	case KDSKBSENT:
 		if (!perm)
 			return -EPERM;
-		len = strnlen_user(u_kbs->kb_string,
-				   sizeof(u_kbs->kb_string) - 1);
+		len = strnlen_user(u_kbs->kb_string, sizeof(u_kbs->kb_string));
 		if (!len)
 			return -EFAULT;
-		if (len > sizeof(u_kbs->kb_string) - 1)
+		if (len > sizeof(u_kbs->kb_string))
 			return -EINVAL;
-		p = kmalloc(len + 1, GFP_KERNEL);
+		p = kmalloc(len, GFP_KERNEL);
 		if (!p)
 			return -ENOMEM;
 		if (copy_from_user(p, u_kbs->kb_string, len)) {
 			kfree(p);
 			return -EFAULT;
 		}
-		p[len] = 0;
+		/*
+		 * Make sure the string is terminated by 0. User could have
+		 * modified it between us running strnlen_user() and copying it.
+		 */
+		p[len - 1] = 0;
 		kfree(kbd->func_table[kb_func]);
 		kbd->func_table[kb_func] = p;
 		break;