inet_diag: fix possible overflow in inet_diag_dump_one_icsk()
inet_diag_dump_one_icsk() allocates too small skb.
Add inet_sk_attr_size() helper right before inet_sk_diag_fill()
so that it can be updated if/when new attributes are added.
iproute2/ss currently does not use this dump_one() interface,
this might explain nobody noticed this problem yet.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 81751f1..592aff3 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -71,6 +71,20 @@
mutex_unlock(&inet_diag_table_mutex);
}
+static size_t inet_sk_attr_size(void)
+{
+ return nla_total_size(sizeof(struct tcp_info))
+ + nla_total_size(1) /* INET_DIAG_SHUTDOWN */
+ + nla_total_size(1) /* INET_DIAG_TOS */
+ + nla_total_size(1) /* INET_DIAG_TCLASS */
+ + nla_total_size(sizeof(struct inet_diag_meminfo))
+ + nla_total_size(sizeof(struct inet_diag_msg))
+ + nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
+ + nla_total_size(TCP_CA_NAME_MAX)
+ + nla_total_size(sizeof(struct tcpvegas_info))
+ + 64;
+}
+
int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
struct sk_buff *skb, struct inet_diag_req_v2 *req,
struct user_namespace *user_ns,
@@ -326,9 +340,7 @@
if (err)
goto out;
- rep = nlmsg_new(sizeof(struct inet_diag_msg) +
- sizeof(struct inet_diag_meminfo) +
- sizeof(struct tcp_info) + 64, GFP_KERNEL);
+ rep = nlmsg_new(inet_sk_attr_size(), GFP_KERNEL);
if (!rep) {
err = -ENOMEM;
goto out;