Re: [PATCH v3 5/5] vfio-user: recycle msg on failure

[Mark Cave-Ayland]

On 01/12/2025 09:56, John Levon wrote:


If we fail to read an incoming request, recycle the message.

Resolves: Coverity CID 1611807
Resolves: Coverity CID 1611808
Signed-off-by: John Levon 
---
  hw/vfio-user/proxy.c | 21 -
  1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/hw/vfio-user/proxy.c b/hw/vfio-user/proxy.c
index d1d63816b3..d06978a74f 100644
--- a/hw/vfio-user/proxy.c
+++ b/hw/vfio-user/proxy.c
@@ -412,11 +412,22 @@ err:
  for (i = 0; i < numfds; i++) {
  close(fdp[i]);
  }
-if (isreply && msg != NULL) {
-/* force an error to keep sending thread from hanging */
-vfio_user_set_error(msg->hdr, EINVAL);
-msg->complete = true;
-qemu_cond_signal(&msg->cv);
+if (msg != NULL) {
+if (msg->type == VFIO_MSG_REQ) {
+/*
+ * Clean up the request message on failure. Change type back to
+ * NOWAIT to free.
+ */
+msg->type = VFIO_MSG_NOWAIT;
+vfio_user_recycle(proxy, msg);
+} else {
+/*
+ * Report an error back to the sender. Sender will recycle msg.
+ */
+vfio_user_set_error(msg->hdr, EINVAL);
+msg->complete = true;
+qemu_cond_signal(&msg->cv);
+}
  }
  return -1;
  }


Reviewed-by: Mark Cave-Ayland 


ATB,

Mark.

[PATCH v3 5/5] vfio-user: recycle msg on failure

[John Levon]

If we fail to read an incoming request, recycle the message.

Resolves: Coverity CID 1611807
Resolves: Coverity CID 1611808
Signed-off-by: John Levon 
---
 hw/vfio-user/proxy.c | 21 -
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/hw/vfio-user/proxy.c b/hw/vfio-user/proxy.c
index d1d63816b3..d06978a74f 100644
--- a/hw/vfio-user/proxy.c
+++ b/hw/vfio-user/proxy.c
@@ -412,11 +412,22 @@ err:
 for (i = 0; i < numfds; i++) {
 close(fdp[i]);
 }
-if (isreply && msg != NULL) {
-/* force an error to keep sending thread from hanging */
-vfio_user_set_error(msg->hdr, EINVAL);
-msg->complete = true;
-qemu_cond_signal(&msg->cv);
+if (msg != NULL) {
+if (msg->type == VFIO_MSG_REQ) {
+/*
+ * Clean up the request message on failure. Change type back to
+ * NOWAIT to free.
+ */
+msg->type = VFIO_MSG_NOWAIT;
+vfio_user_recycle(proxy, msg);
+} else {
+/*
+ * Report an error back to the sender. Sender will recycle msg.
+ */
+vfio_user_set_error(msg->hdr, EINVAL);
+msg->complete = true;
+qemu_cond_signal(&msg->cv);
+}
 }
 return -1;
 }
-- 
2.43.0