syzbot reported a kernel warning in xfrm_state_fini(), which indicates that we have entries left in the list net->xfrm.state_all whose proto is zero. And xfrm_id_proto_match() doesn't consider them as a match with IPSEC_PROTO_ANY in this case.
Proto with value 0 is probably not a valid value, at least verify_newsa_info() doesn't consider it valid either. This patch fixes it by checking the proto value in validate_tmpl() and rejecting invalid ones, like what iproute2 does in xfrm_xfrmproto_getbyname(). Reported-by: syzbot <syzkal...@googlegroups.com> Cc: Steffen Klassert <steffen.klass...@secunet.com> Cc: Herbert Xu <herb...@gondor.apana.org.au> Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com> --- net/xfrm/xfrm_user.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 983b0233767b..c2cfcc6fdb34 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1445,6 +1445,21 @@ static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family) default: return -EINVAL; } + + switch (ut[i].id.proto) { + case IPPROTO_AH: + case IPPROTO_ESP: + case IPPROTO_COMP: +#if IS_ENABLED(CONFIG_IPV6) + case IPPROTO_ROUTING: + case IPPROTO_DSTOPTS: +#endif + case IPSEC_PROTO_ANY: + break; + default: + return -EINVAL; + } + } return 0; -- 2.13.0