dccp qpolicy: Parameter checking of cmsg qpolicy parameters
Ensure that cmsg->cmsg_type value is valid for qpolicy
that is currently in use.
Signed-off-by: Tomasz Grobelny <tomasz@grobelny.oswiecenia.net>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h
index d008da9..48ad5d9 100644
--- a/net/dccp/dccp.h
+++ b/net/dccp/dccp.h
@@ -251,6 +251,7 @@
extern void dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb);
extern struct sk_buff *dccp_qpolicy_top(struct sock *sk);
extern struct sk_buff *dccp_qpolicy_pop(struct sock *sk);
+extern bool dccp_qpolicy_param_ok(struct sock *sk, __be32 param);
/*
* TX Packet Output and TX Timers
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index d6a2249..152975d 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -726,6 +726,10 @@
if (cmsg->cmsg_level != SOL_DCCP)
continue;
+ if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX &&
+ !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type))
+ return -EINVAL;
+
switch (cmsg->cmsg_type) {
case DCCP_SCM_PRIORITY:
if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32)))
diff --git a/net/dccp/qpolicy.c b/net/dccp/qpolicy.c
index 4b0fd6b..63c30bf 100644
--- a/net/dccp/qpolicy.c
+++ b/net/dccp/qpolicy.c
@@ -73,17 +73,20 @@
void (*push) (struct sock *sk, struct sk_buff *skb);
bool (*full) (struct sock *sk);
struct sk_buff* (*top) (struct sock *sk);
+ __be32 params;
} qpol_table[DCCPQ_POLICY_MAX] = {
[DCCPQ_POLICY_SIMPLE] = {
- .push = qpolicy_simple_push,
- .full = qpolicy_simple_full,
- .top = qpolicy_simple_top,
+ .push = qpolicy_simple_push,
+ .full = qpolicy_simple_full,
+ .top = qpolicy_simple_top,
+ .params = 0,
},
[DCCPQ_POLICY_PRIO] = {
- .push = qpolicy_simple_push,
- .full = qpolicy_prio_full,
- .top = qpolicy_prio_best_skb,
+ .push = qpolicy_simple_push,
+ .full = qpolicy_prio_full,
+ .top = qpolicy_prio_best_skb,
+ .params = DCCP_SCM_PRIORITY,
},
};
@@ -124,3 +127,11 @@
}
return skb;
}
+
+bool dccp_qpolicy_param_ok(struct sock *sk, __be32 param)
+{
+ /* check if exactly one bit is set */
+ if (!param || (param & (param - 1)))
+ return false;
+ return (qpol_table[dccp_sk(sk)->dccps_qpolicy].params & param) == param;
+}