xfrm: check id proto in validate_tmpl()

commit 6a53b75 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 <[email protected]> Cc: Steffen Klassert <[email protected]> Cc: Herbert Xu <[email protected]> Signed-off-by: Cong Wang <[email protected]> Signed-off-by: Steffen Klassert <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
nemunaire · Feb 25, 2018 · a04a3d1 · a04a3d1
1 parent 2796fe7
commit a04a3d1
Showing 1 changed file with 15 additions and 0 deletions.
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
@@ -1375,6 +1375,21 @@ 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;