Commit d921fea338 ("ui/vnc-clipboard: fix infinite loop in
inflate_buffer (CVE-2023-3255)") removed this hunk, but it is still
required, because it can happen that stream.avail_in becomes zero
before coming across a return value of Z_STREAM_END in the loop.
This fixes the host->guest direction of the clipboard with noVNC and
TigerVNC as clients.
Fixes: d921fea338 ("ui/vnc-clipboard: fix infinite loop in inflate_buffer (CVE-2023-3255)")
Reported-by: Friedrich Weber <f.weber@proxmox.com>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20231122125826.228189-1-f.ebner@proxmox.com>
A wrong exit condition may lead to an infinite loop when inflating a
valid zlib buffer containing some extra bytes in the `inflate_buffer`
function. The bug only occurs post-authentication. Return the buffer
immediately if the end of the compressed data has been reached
(Z_STREAM_END).
Fixes: CVE-2023-3255
Fixes: 0bf41cab ("ui/vnc: clipboard support")
Reported-by: Kevin Denis <kevin.denis@synacktiv.com>
Signed-off-by: Mauro Matteo Cascella <mcascell@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20230704084210.101822-1-mcascell@redhat.com>
Use a QemuClipboardNotify union type for extendable clipboard events.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
vnc_server_cut_text_caps() is not guaranteed to be called only once.
If it called twice, we finally call notifier_list_add() twice with same
element. Which leads to loopback QLIST. So, on next
notifier_list_notify() we'll loop forever and QEMU stuck.
So, let's only register new notifier if it's not yet registered.
Note, that similar check is used in vdagent_chr_recv_caps() (before
call qemu_clipboard_peer_register()), and also before
qemu_clipboard_peer_unregister() call in vdagent_disconnect() and in
vnc_disconnect_finish().
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20211110103800.2266729-1-vsementsov@virtuozzo.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch adds support for cut+paste to the qemu vnc server, which
allows the vnc client exchange clipbaord data with qemu and other peers
like the qemu vdagent implementation.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20210519053940.1888907-1-kraxel@redhat.com
Message-Id: <20210519053940.1888907-8-kraxel@redhat.com>
