Include followup patch related to CVE-2021-3716.

This commit is contained in:
Eric Blake 2021-08-19 16:25:37 -05:00
parent 03411c4a44
commit 034cff3866
2 changed files with 45 additions and 1 deletions

View File

@ -0,0 +1,38 @@
From 6c5faac6a37077cf2366388a80862bb00616d0d8 Mon Sep 17 00:00:00 2001
From: Eric Blake <eblake@redhat.com>
Date: Mon, 16 Aug 2021 13:43:29 -0500
Subject: [nbdkit PATCH] server: reset meta context replies on starttls
Related to CVE-2021-3716, but not as severe. No compliant client will
send NBD_CMD_BLOCK_STATUS unless it first negotiates
NBD_OPT_SET_META_CONTEXT. If an attacker injects a premature
SET_META_CONTEXT, either the client will never notice (because it
never uses BLOCK_STATUS), or the client will overwrite the attacker's
attempt with the client's own SET_META_CONTEXT request after
encryption is enabled. So I don't class this as having the potential
to trigger denial-of-service due to any protocol mismatch between
compliant client and server (I don't care what happens with
non-compliant clients).
Fixes: 26455d45 (server: protocol: Implement Block Status "base:allocation".)
---
server/protocol-handshake-newstyle.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/server/protocol-handshake-newstyle.c b/server/protocol-handshake-newstyle.c
index 7e6b7b1b..79b2c8ce 100644
--- a/server/protocol-handshake-newstyle.c
+++ b/server/protocol-handshake-newstyle.c
@@ -497,6 +497,9 @@ negotiate_handshake_newstyle_options (void)
debug ("using TLS on this connection");
/* Wipe out any cached state. */
conn->structured_replies = false;
+ free (conn->exportname_from_set_meta_context);
+ conn->exportname_from_set_meta_context = NULL;
+ conn->meta_context_base_allocation = false;
for_each_backend (b) {
free (conn->default_exportname[b->i]);
conn->default_exportname[b->i] = NULL;
--
2.31.1

View File

@ -51,7 +51,7 @@ ExclusiveArch: x86_64
Name: nbdkit Name: nbdkit
Version: 1.27.7 Version: 1.27.7
Release: 1%{?dist} Release: 2%{?dist}
Summary: NBD server Summary: NBD server
License: BSD License: BSD
@ -72,6 +72,9 @@ Source2: libguestfs.keyring
# Maintainer script which helps with handling patches. # Maintainer script which helps with handling patches.
Source3: copy-patches.sh Source3: copy-patches.sh
# Fix SET_META_CONTEXT leaking state across STARTTLS
Patch1: 0001-server-reset-meta-context-replies-on-starttls.patch
BuildRequires: make BuildRequires: make
%if 0%{patches_touch_autotools} %if 0%{patches_touch_autotools}
BuildRequires: autoconf, automake, libtool BuildRequires: autoconf, automake, libtool
@ -1241,6 +1244,9 @@ export LIBGUESTFS_TRACE=1
%changelog %changelog
* Thu Aug 19 2021 Eric Blake <eblake@redhat.com> - 1.27.7-2
- Include followup patch related to CVE-2021-3716.
* Thu Aug 19 2021 Eric Blake <eblake@redhat.com> - 1.27.7-1 * Thu Aug 19 2021 Eric Blake <eblake@redhat.com> - 1.27.7-1
- New upstream development version 1.27.7; addresses CVE-2021-3716. - New upstream development version 1.27.7; addresses CVE-2021-3716.