diff mbox series

[PULL,5/8] hw/usb/canokey: Fix CCID ZLP

Message ID 20220704075946.921883-6-kraxel@redhat.com
State New
Headers show
Series [PULL,1/8] Rename docs/specs/fw_cfg.txt to .rst | expand

Commit Message

Gerd Hoffmann July 4, 2022, 7:59 a.m. UTC
From: "Hongren (Zenithal) Zheng" <i@zenithal.me>

CCID could send zero-length packet (ZLP)
if we invoke two data_in, two packets would be concated
and we could not distinguish them.

The CANOKEY_EMU_EP_CTAPHID is imported from canokey-qemu.h

Reported-by: MkfsSion <myychina28759@gmail.com>
Signed-off-by: Hongren (Zenithal) Zheng <i@zenithal.me>
Message-Id: <YqcqGz0s3+LE42ms@Sun>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/usb/canokey.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/hw/usb/canokey.c b/hw/usb/canokey.c
index 4a08b1cbd776..86548923eb16 100644
--- a/hw/usb/canokey.c
+++ b/hw/usb/canokey.c
@@ -109,11 +109,10 @@  int canokey_emu_transmit(
      * Note: this is a quirk for CanoKey CTAPHID
      * because it calls multiple emu_transmit in one device_loop
      * but w/o data_in it would stuck in device_loop
-     * This has no side effect for CCID as it is strictly
-     * OUT then IN transfer
-     * However it has side effect for Control transfer
+     * This has side effect for CCID since CCID can send ZLP
+     * This also has side effect for Control transfer
      */
-    if (ep_in != 0) {
+    if (ep_in == CANOKEY_EMU_EP_CTAPHID) {
         canokey_emu_data_in(ep_in);
     }
     return 0;