Message ID | 20220214115917.1679568-1-marcandre.lureau@redhat.com |
---|---|
State | New |
Headers | show |
Series | ui/clipboard: fix use-after-free regression | expand |
On Mon, Feb 14, 2022 at 03:59:17PM +0400, marcandre.lureau@redhat.com wrote: > From: Marc-André Lureau <marcandre.lureau@redhat.com> > > The same info may be used to update the clipboard, and may be freed > before being ref'ed again. Ewww, subtle. > Fixes: 70a54b01693ed ("ui: avoid compiler warnings from unused clipboard info variable") > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > --- > ui/clipboard.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/ui/clipboard.c b/ui/clipboard.c > index 5f15cf853d07..9079ef829b51 100644 > --- a/ui/clipboard.c > +++ b/ui/clipboard.c > @@ -66,8 +66,10 @@ void qemu_clipboard_update(QemuClipboardInfo *info) > > notifier_list_notify(&clipboard_notifiers, ¬ify); > > - qemu_clipboard_info_unref(cbinfo[info->selection]); > - cbinfo[info->selection] = qemu_clipboard_info_ref(info); > + if (cbinfo[info->selection] != info) { > + qemu_clipboard_info_unref(cbinfo[info->selection]); > + cbinfo[info->selection] = qemu_clipboard_info_ref(info); > + } > } Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Regards, Daniel
diff --git a/ui/clipboard.c b/ui/clipboard.c index 5f15cf853d07..9079ef829b51 100644 --- a/ui/clipboard.c +++ b/ui/clipboard.c @@ -66,8 +66,10 @@ void qemu_clipboard_update(QemuClipboardInfo *info) notifier_list_notify(&clipboard_notifiers, ¬ify); - qemu_clipboard_info_unref(cbinfo[info->selection]); - cbinfo[info->selection] = qemu_clipboard_info_ref(info); + if (cbinfo[info->selection] != info) { + qemu_clipboard_info_unref(cbinfo[info->selection]); + cbinfo[info->selection] = qemu_clipboard_info_ref(info); + } } QemuClipboardInfo *qemu_clipboard_info(QemuClipboardSelection selection)