4.4-stable review patch. If anyone has any objections, please let me know.
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From: Cong Wang xiyou.wangcong@gmail.com
commit 6a53b7593233ab9e4f96873ebacc0f653a55c3e1 upstream.
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 syzkaller@googlegroups.com Cc: Steffen Klassert steffen.klassert@secunet.com Cc: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: Steffen Klassert steffen.klassert@secunet.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/xfrm/xfrm_user.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
--- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1402,6 +1402,21 @@ static int validate_tmpl(int nr, struct 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;