commit 8fd61d34226014fe7886babfca6f45a7eff89d25
author Mathias Krause <minipli@googlemail.com> Tue Feb 05 18:19:15 2013 +0100
committer Herbert Xu <herbert@gondor.apana.org.au> Tue Feb 19 20:27:04 2013 +0800
tree f20387d290768d8989ddf9263f8757acdd8447fc
parent e336ed9647b06e3bb52995dbc51101cbdf39f2a2

crypto: user - ensure user supplied strings are nul-terminated

To avoid misuse, ensure cru_name and cru_driver_name are always
nul-terminated strings.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/crypto_user.c

diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
index 423a267..dfd511f 100644
--- a/crypto/crypto_user.c
+++ b/crypto/crypto_user.c
@@ -30,6 +30,8 @@
 
 #include "internal.h"
 
+#define null_terminated(x)	(strnlen(x, sizeof(x)) < sizeof(x))
+
 static DEFINE_MUTEX(crypto_cfg_mutex);
 
 /* The crypto netlink socket */
@@ -196,6 +198,9 @@
 	struct crypto_dump_info info;
 	int err;
 
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
 	if (!p->cru_driver_name[0])
 		return -EINVAL;
 
@@ -260,6 +265,9 @@
 	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
 	LIST_HEAD(list);
 
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
 	if (priority && !strlen(p->cru_driver_name))
 		return -EINVAL;
 
@@ -287,6 +295,9 @@
 	struct crypto_alg *alg;
 	struct crypto_user_alg *p = nlmsg_data(nlh);
 
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
 	alg = crypto_alg_match(p, 1);
 	if (!alg)
 		return -ENOENT;
@@ -368,6 +379,9 @@
 	struct crypto_user_alg *p = nlmsg_data(nlh);
 	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
 
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
 	if (strlen(p->cru_driver_name))
 		exact = 1;