diff options
| author |   tb <tb@openbsd.org> | 2020-05-21 19:15:54 +0000 |
|---|---|---|
| committer | tb <tb@openbsd.org> | 2020-05-21 19:15:54 +0000 |
| commit | 83aac8c820afdec58f27a92fda2a01498b4502c8 (patch) | |
| tree | 6e2f4f2d0f9c33ad60091e22ad2b464d0a5c0e76 /lib/libssl/tls13_lib.c | |
| parent | beck fixed most of the keyupdate tests. update annotation (diff) | |
| download | wireguard-openbsd-83aac8c820afdec58f27a92fda2a01498b4502c8.tar.xz wireguard-openbsd-83aac8c820afdec58f27a92fda2a01498b4502c8.zip | |
A failure of tls13_handshake_msg_new() could lead to a NULL deref
in the following tls13_handshake_msg_start() call. Add a check.
Stop clobbering the ctx's hs_msg variable, use a local variable
instead.
ok beck jsing
Diffstat (limited to 'lib/libssl/tls13_lib.c')
| -rw-r--r-- | lib/libssl/tls13_lib.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/lib/libssl/tls13_lib.c b/lib/libssl/tls13_lib.c index 60b4a389b7e..41cb70d8185 100644 --- a/lib/libssl/tls13_lib.c +++ b/lib/libssl/tls13_lib.c @@ -1,4 +1,4 @@ -/* $OpenBSD: tls13_lib.c,v 1.46 2020/05/19 01:30:34 beck Exp $ */ +/* $OpenBSD: tls13_lib.c,v 1.47 2020/05/21 19:15:54 tb Exp $ */ /* * Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org> * Copyright (c) 2019 Bob Beck <beck@openbsd.org> @@ -258,6 +258,7 @@ tls13_phh_limit_check(struct tls13_ctx *ctx) static ssize_t tls13_key_update_recv(struct tls13_ctx *ctx, CBS *cbs) { + struct tls13_handshake_msg *hs_msg = NULL; uint8_t alert = TLS13_ALERT_INTERNAL_ERROR; uint8_t key_update_request; ssize_t ret; @@ -278,31 +279,34 @@ tls13_key_update_recv(struct tls13_ctx *ctx, CBS *cbs) if (!tls13_phh_update_peer_traffic_secret(ctx)) goto err; - if (key_update_request) { + if (key_update_request == 1) { CBB cbb; CBS cbs; /* XXX */ - tls13_handshake_msg_free(ctx->hs_msg); - ctx->hs_msg = tls13_handshake_msg_new(); - - if (!tls13_handshake_msg_start(ctx->hs_msg, &cbb, TLS13_MT_KEY_UPDATE)) + if ((hs_msg = tls13_handshake_msg_new()) == NULL) + goto err; + if (!tls13_handshake_msg_start(hs_msg, &cbb, + TLS13_MT_KEY_UPDATE)) goto err; if (!CBB_add_u8(&cbb, 0)) goto err; - if (!tls13_handshake_msg_finish(ctx->hs_msg)) + if (!tls13_handshake_msg_finish(hs_msg)) goto err; - ctx->key_update_request = key_update_request; - tls13_handshake_msg_data(ctx->hs_msg, &cbs); + ctx->key_update_request = 1; + tls13_handshake_msg_data(hs_msg, &cbs); ret = tls13_record_layer_phh(ctx->rl, &cbs); - tls13_handshake_msg_free(ctx->hs_msg); - ctx->hs_msg = NULL; + tls13_handshake_msg_free(hs_msg); + hs_msg = NULL; } else ret = TLS13_IO_SUCCESS; return ret; + err: + tls13_handshake_msg_free(hs_msg); + return tls13_send_alert(ctx->rl, alert); } |