[libcamera-devel] [PATCH v2 16/17] v4l2: v4l2_camera_proxy: Don't allow buffers to be freed if still mmaped

[Paul Elder]

In VIDIOC_REQBUFS with count = 0, if the buffers are still mmaped, they
should not be allowed to be freed. Add a check for this.

Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>

---
New in v2
- split from "Fix v4l2-compliance streaming tests"
---
 src/v4l2/v4l2_camera_proxy.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp
index a7f987a..2eb2fcc 100644
--- a/src/v4l2/v4l2_camera_proxy.cpp
+++ b/src/v4l2/v4l2_camera_proxy.cpp
@@ -467,6 +467,9 @@ int V4L2CameraProxy::vidioc_reqbufs(V4L2CameraFile *cf, struct v4l2_requestbuffe
 	memset(arg->reserved, 0, sizeof(arg->reserved));
 
 	if (arg->count == 0) {
+		if (!mmaps_.empty())
+			return -EBUSY;
+
 		if (vcam_->isRunning()) {
 			for (struct v4l2_buffer &buf : buffers_)
 				buf.flags &= ~(V4L2_BUF_FLAG_QUEUED | V4L2_BUF_FLAG_DONE);
-- 
2.27.0