diff options
| -rw-r--r-- | src/v4l2/v4l2_camera_proxy.cpp | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp index 55ff62cd..341f7902 100644 --- a/src/v4l2/v4l2_camera_proxy.cpp +++ b/src/v4l2/v4l2_camera_proxy.cpp @@ -778,10 +778,20 @@ const std::set<unsigned long> V4L2CameraProxy::supportedIoctls_ = { VIDIOC_STREAMOFF, }; -int V4L2CameraProxy::ioctl(V4L2CameraFile *file, unsigned long request, void *arg) +int V4L2CameraProxy::ioctl(V4L2CameraFile *file, unsigned long longRequest, void *arg) { MutexLocker locker(proxyMutex_); + /* + * The Linux Kernel only processes 32 bits of an IOCTL. + * + * Prevent unexpected sign-extensions that could occur if applications + * use a signed int for the ioctl request, which would sign-extend to + * an incorrect value for unsigned longs on 64 bit architectures by + * explicitly casting as an unsigned int here. + */ + unsigned int request = longRequest; + if (!arg && (_IOC_DIR(request) & _IOC_WRITE)) { errno = EFAULT; return -1; |