[IPSEC]: Fixed alg_key_len usage in attach_one_algo

The variable alg_key_len is in bits and not bytes.  The function
attach_one_algo is currently using it as if it were in bytes.
This causes it to read memory which may not be there.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 5ddda2c98af9..15ba08602aa1 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -162,6 +162,7 @@ static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
         struct rtattr *rta = u_arg;
         struct xfrm_algo *p, *ualg;
         struct xfrm_algo_desc *algo;
+        int len;
 
         if (!rta)
                 return 0;
@@ -173,11 +174,12 @@ static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
                 return -ENOSYS;
         *props = algo->desc.sadb_alg_id;
 
-        p = kmalloc(sizeof(*ualg) + ualg->alg_key_len, GFP_KERNEL);
+        len = sizeof(*ualg) + (ualg->alg_key_len + 7U) / 8;
+        p = kmalloc(len, GFP_KERNEL);
         if (!p)
                 return -ENOMEM;
 
-        memcpy(p, ualg, sizeof(*ualg) + ualg->alg_key_len);
+        memcpy(p, ualg, len);
         *algpp = p;
         return 0;
 }