[PATCH net 4/4] sctp: add param size validation for SCTP_PARAM_SET_PRIMARY
From: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Date: 2021-06-28 19:14:03
Also in:
linux-sctp
Subsystem:
networking [general], sctp protocol, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Marcelo Ricardo Leitner, Xin Long, Linus Torvalds
When SCTP handles an INIT chunk, it calls for example:
sctp_sf_do_5_1B_init
sctp_verify_init
sctp_verify_param
sctp_process_init
sctp_process_param
handling of SCTP_PARAM_SET_PRIMARY
sctp_verify_init() wasn't doing proper size validation and neither the
later handling, allowing it to work over the chunk itself, possibly being
uninitialized memory.
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
---
net/sctp/sm_make_chunk.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index f33a870b483da7123e2ddb4473b6200a1aca5ade..587fb3cb88e29f53148cd21f13a2a86487ce292b 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c@@ -2166,9 +2166,16 @@ static enum sctp_ierror sctp_verify_param(struct net *net, break; case SCTP_PARAM_SET_PRIMARY: - if (ep->asconf_enable) - break; - goto unhandled; + if (!ep->asconf_enable) + goto unhandled; + + if (ntohs(param.p->length) < sizeof(struct sctp_addip_param) + + sizeof(struct sctp_paramhdr)) { + sctp_process_inv_paramlength(asoc, param.p, + chunk, err_chunk); + retval = SCTP_IERROR_ABORT; + } + break; case SCTP_PARAM_HOST_NAME_ADDRESS: /* Tell the peer, we won't support this param. */
--
2.31.1