[libcamera-devel] [PATCH] libcamera: v4l2_videodevice: Fix potential errno overwrite

[Laurent Pinchart]

The errno variable can potentially be overwritten by operator<<(). Store
it in a local variable before logging the error message.

Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 src/libcamera/v4l2_videodevice.cpp | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
index 009f6d55610f..0830be80c553 100644
--- a/src/libcamera/v4l2_videodevice.cpp
+++ b/src/libcamera/v4l2_videodevice.cpp
@@ -647,14 +647,17 @@ int V4L2VideoDevice::open()
  */
 int V4L2VideoDevice::open(SharedFD handle, enum v4l2_buf_type type)
 {
+	int ret;
+
 	UniqueFD newFd = handle.dup();
 	if (!newFd.isValid()) {
+		ret = -errno;
 		LOG(V4L2, Error) << "Failed to duplicate file handle: "
-				 << strerror(errno);
-		return -errno;
+				 << strerror(-ret);
+		return ret;
 	}
 
-	int ret = V4L2Device::setFd(std::move(newFd));
+	ret = V4L2Device::setFd(std::move(newFd));
 	if (ret < 0) {
 		LOG(V4L2, Error) << "Failed to set file handle: "
 				 << strerror(-ret);
-- 
Regards,

Laurent Pinchart