[+to libvirt development list, since this looks like a libvirt patch, not a Linux kernel patch] On Thu, Jun 26, 2025 at 02:10:38PM +0800, liu.xuemei1@zte.com.cn wrote:

From: Liu Song <liu.song13@zte.com.cn>

The ff callback is never called in remoteStreamCallbackFree() because cbdata->cb can not be NULL. This causes a leak of 'cbdata->opaque'.

The leak can be reproduced by attaching and detaching to the console of an VM using `virsh console`.

ASAN reports the leak stack as: Direct leak of 288 byte(s) in 1 object(s) allocated from: #0 0x7f6edf6ba0c7 in calloc (/lib64/libasan.so.8+0xba0c7) #1 0x7f6edf5175b0 in g_malloc0 (/lib64/libglib-2.0.so.0+0x615b0) #2 0x7f6ede6d0be3 in g_type_create_instance (/lib64/libgobject-2.0.so.0+0x3cbe3) #3 0x7f6ede6b82cf in g_object_new_internal (/lib64/libgobject-2.0.so.0+0x242cf) #4 0x7f6ede6b9877 in g_object_new_with_properties (/lib64/libgobject-2.0.so.0+0x25877) #5 0x7f6ede6ba620 in g_object_new (/lib64/libgobject-2.0.so.0+0x26620) #6 0x7f6edeb78138 in virObjectNew ../src/util/virobject.c:252 #7 0x7f6edeb7a78b in virObjectLockableNew ../src/util/virobject.c:274 #8 0x558251e427e1 in virConsoleNew ../tools/virsh-console.c:369 #9 0x558251e427e1 in virshRunConsole ../tools/virsh-console.c:427

Signed-off-by: Liu Song <liu.song13@zte.com.cn> --- src/remote/remote_daemon_stream.c | 2 +- src/remote/remote_driver.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/remote/remote_daemon_stream.c b/src/remote/remote_daemon_stream.c index 453728a66b..a5032f9a43 100644 --- a/src/remote/remote_daemon_stream.c +++ b/src/remote/remote_daemon_stream.c @@ -437,13 +437,13 @@ int daemonAddClientStream(virNetServerClient *client, return -1; }

+ virObjectRef(client); if (virStreamEventAddCallback(stream->st, 0, daemonStreamEvent, client, virObjectUnref) < 0) return -1;

virObjectRef(client); - if ((stream->filterID = virNetServerClientAddFilter(client, daemonStreamFilter, stream)) < 0) { diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c index 2690c05267..9ac13469e9 100644 --- a/src/remote/remote_driver.c +++ b/src/remote/remote_driver.c @@ -5336,7 +5336,7 @@ static void remoteStreamCallbackFree(void *opaque) { struct remoteStreamCallbackData *cbdata = opaque;

- if (!cbdata->cb && cbdata->ff) + if (cbdata->ff) (cbdata->ff)(cbdata->opaque);

virObjectUnref(cbdata->st); -- 2.27.0