From: Wei Yongjun <yjwei@xxxxxxxxxxxxxx>
RFC4340 states that if a packet is received with an option error (such as a
Mandatory Option as the last byte of the option list), the endpoint should
repond with a Reset.
In the LISTEN and RESPOND states, the endpoint correctly reponds with Reset,
while in the REQUEST/OPEN states, packets with option errors are just ignored.
The packet sequence is as follows:
Case 1:
Endpoint A Endpoint B
(CLOSED) (CLOSED)
<---------------- REQUEST
RESPONSE -----------------> (*1)
(with invalid option)
<---------------- RESET
(with Reset Code 5, "Option Error")
(*1) currently just ignored, no Reset is sent
Case 2:
Endpoint A Endpoint B
(OPEN) (OPEN)
DATA-ACK -----------------> (*2)
(with invalid option)
<---------------- RESET
(with Reset Code 5, "Option Error")
(*2) currently just ignored, no Reset is sent
This patch fixes the problem, by generating a Reset instead of silently
ignoring option errors.
Signed-off-by: Wei Yongjun <yjwei@xxxxxxxxxxxxxx>
Acked-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Acked-by: Gerrit Renker <gerrit@xxxxxxxxxxxxxx>
---
net/dccp/input.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -370,7 +370,7 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
goto discard;
if (dccp_parse_options(sk, NULL, skb))
- goto discard;
+ return 1;
if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
dccp_event_ack_recv(sk, skb);
@@ -610,7 +610,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
* Step 8: Process options and mark acknowledgeable
*/
if (dccp_parse_options(sk, NULL, skb))
- goto discard;
+ return 1;
if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
dccp_event_ack_recv(sk, skb);
--
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