From: Xin Long <lucien.xin@gmail.com> mainline inclusion from mainline commit aa0f697e45286a6b5f0ceca9418acf54b9099d99 bugzilla: 182989 https://gitee.com/openeuler/kernel/issues/I4DDEL CVE: CVE-2021-3772 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- 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: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Reviewed-by: Yue Haibing <yuehaibing@huawei.com> Reviewed-by: weiyang wang <wangweiyang2@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- net/sctp/sm_statefuns.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 8930f35450ae..e5dd395668ce 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -4570,6 +4570,9 @@ 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, -- 2.20.1