host_memory_backend_set_host_nodes() was not validating host-nodes before writing to backend->host_nodes, making QEMU write beyond the end of the bitmap.
Fix the crash and add a simple regression test for the fix. Reported-by: Markus Armbruster <arm...@redhat.com> Signed-off-by: Eduardo Habkost <ehabk...@redhat.com> --- backends/hostmem.c | 13 +++++++--- tests/acceptance/host-nodes-limit.py | 36 ++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+), 3 deletions(-) create mode 100644 tests/acceptance/host-nodes-limit.py diff --git a/backends/hostmem.c b/backends/hostmem.c index 1a89342039..ef199d32fd 100644 --- a/backends/hostmem.c +++ b/backends/hostmem.c @@ -103,11 +103,18 @@ host_memory_backend_set_host_nodes(Object *obj, Visitor *v, const char *name, { #ifdef CONFIG_NUMA HostMemoryBackend *backend = MEMORY_BACKEND(obj); - uint16List *l = NULL; + uint16List *l, *host_nodes = NULL; - visit_type_uint16List(v, name, &l, errp); + visit_type_uint16List(v, name, &host_nodes, errp); + + for (l = host_nodes; l; l = l->next) { + if (l->value >= MAX_NODES) { + error_setg(errp, "Invalid host-nodes value: %d", l->value); + return; + } + } - while (l) { + for (l = host_nodes; l; l = l->next) { bitmap_set(backend->host_nodes, l->value, 1); l = l->next; } diff --git a/tests/acceptance/host-nodes-limit.py b/tests/acceptance/host-nodes-limit.py new file mode 100644 index 0000000000..e803e10104 --- /dev/null +++ b/tests/acceptance/host-nodes-limit.py @@ -0,0 +1,36 @@ +# Regression test for host-nodes limit validation +# +# Copyright (c) 2018 Red Hat, Inc. +# +# Author: +# Eduardo Habkost <ehabk...@redhat.com> +# +# This work is licensed under the terms of the GNU GPL, version 2 or +# later. See the COPYING file in the top-level directory. + +from avocado_qemu import Test +from subprocess import Popen, PIPE + +MAX_NODES = 128 + +class HostNodesValidation(Test): + def test_large_host_nodes(self): + p = Popen([self.qemu_bin, '-display', 'none', '-nodefaults', + '-object', 'memory-backend-ram,id=m0,' + 'size=4096,host-nodes=%d' % (MAX_NODES)], + stderr=PIPE, stdout=PIPE) + stdout,stderr = p.communicate() + + self.assertIn(b'Invalid host-nodes', stderr) + self.assertEquals(stdout, b'') + self.assertEquals(p.returncode, 1) + + def test_valid_host_nodes(self): + p = Popen([self.qemu_bin, '-display', 'none', '-nodefaults', + '-object', 'memory-backend-ram,id=m0,' + 'size=4096,host-nodes=%d' % (MAX_NODES - 1)], + stderr=PIPE, stdout=PIPE) + stdout,stderr = p.communicate() + + self.assertIn(b'host-nodes must be empty', stderr) + self.assertEquals(p.returncode, 1) -- 2.18.0.rc1.1.g3f1ff2140