Commit aa0f697e authored by Xin Long's avatar Xin Long Committed by Jakub Kicinski
Browse files

sctp: add vtag check in sctp_sf_violation 



sctp_sf_violation() is called when processing HEARTBEAT_ACK chunk
in cookie_wait state, and some other places are also using it.

The vtag in the chunk's sctphdr should be verified, otherwise, as
later in chunk length check, it may send abort with the existent
asoc's vtag, which can be exploited by one to cook a malicious
chunk to terminate a SCTP asoc.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Acked-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent a64b341b

net/sctp/sm_statefuns.c

+3 −0
Original line number Diff line number Diff line
@@ -4669,6 +4669,9 @@ enum sctp_disposition sctp_sf_violation(struct net *net, 
{

	struct sctp_chunk *chunk = arg;



	if (!sctp_vtag_verify(chunk, asoc))

		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);



	/* Make sure that the chunk has a valid length. */

	if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr)))

		return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,