in sctp_process_asconf(), we get address parameter from the beginning of
the addip params. but we never check if it's really there. if the addr
param is not there, it still can pass sctp_verify_asconf(), then to be
handled by sctp_process_asconf(), it will not be safe.
so add a code in sctp_verify_asconf() to check the address parameter is in
the beginning, or return false to send abort.
v2->v3:
* put the check in the loop, add the check for multiple address parameters.
v1->v2:
* put the check behind the params' length verify.
Signed-off-by: Xin Long <lucien....@gmail.com>
Signed-off-by: Vlad Yasevich <vyase...@redhat.com>
---
net/sctp/sm_make_chunk.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 06320c8..4068fe1 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -3130,14 +3130,24 @@ bool sctp_verify_asconf(const struct sctp_association
*asoc,
case SCTP_PARAM_ERR_CAUSE:
break;
case SCTP_PARAM_IPV4_ADDRESS:
+ if (addr_param_seen) {
+ /* peer placed multiple address parameters into
+ * the same asconf. reject it.
+ */
+ return false;
+ }
if (length != sizeof(sctp_ipv4addr_param_t))
return false;
- addr_param_seen = true;
+ if (param.v == addip->addip_hdr.params)
+ addr_param_seen = true;
break;
case SCTP_PARAM_IPV6_ADDRESS:
+ if (addr_param_seen)
+ return false;
if (length != sizeof(sctp_ipv6addr_param_t))
return false;
- addr_param_seen = true;
+ if (param.v == addip->addip_hdr.params)
+ addr_param_seen = true;
break;
case SCTP_PARAM_ADD_IP:
case SCTP_PARAM_DEL_IP:
--
2.1.0
--
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