From 282a4de8f00fd3b37f69d9e65086937771fdf8aa Mon Sep 17 00:00:00 2001 From: Marcelo Ricardo Leitner Date: Mon, 28 Jun 2021 16:13:43 -0300 Subject: [PATCH] UPSTREAM: sctp: validate chunk size in __rcv_asconf_lookup commit b6ffe7671b24689c09faa5675dd58f93758a97ae upstream. In one of the fallbacks that SCTP has for identifying an association for an incoming packet, it looks for AddIp chunk (from ASCONF) and take a peek. Thing is, at this stage nothing was validating that the chunk actually had enough content for that, allowing the peek to happen over uninitialized memory. Similar check already exists in actual asconf handling in sctp_verify_asconf(). Bug: 197154735 Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Aaron Ding Change-Id: Ibfe53fc724143423353ed6b2984d2508ee4fc457 --- net/sctp/input.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sctp/input.c b/net/sctp/input.c index ddb5b5c2550e..49c49a4d203f 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -1168,6 +1168,9 @@ static struct sctp_association *__sctp_rcv_asconf_lookup( union sctp_addr_param *param; union sctp_addr paddr; + if (ntohs(ch->length) < sizeof(*asconf) + sizeof(struct sctp_paramhdr)) + return NULL; + /* Skip over the ADDIP header and find the Address parameter */ param = (union sctp_addr_param *)(asconf + 1);