[PATCH] ebcdic do_kdsk_ioctl off-by-one
Add a missing return check from strnlen_user and fixes a off-by-one when
terminating the string with zero.
Signed-off-by: Davi Arnaut <davi.arnaut@gmail.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/s390/char/keyboard.c b/drivers/s390/char/keyboard.c
index 5bda234..a317a12 100644
--- a/drivers/s390/char/keyboard.c
+++ b/drivers/s390/char/keyboard.c
@@ -440,7 +440,11 @@
return -EPERM;
len = strnlen_user(u_kbs->kb_string,
sizeof(u_kbs->kb_string) - 1);
- p = kmalloc(len, GFP_KERNEL);
+ if (!len)
+ return -EFAULT;
+ if (len > sizeof(u_kbs->kb_string) - 1)
+ return -EINVAL;
+ p = kmalloc(len + 1, GFP_KERNEL);
if (!p)
return -ENOMEM;
if (copy_from_user(p, u_kbs->kb_string, len)) {