[libcamera-devel] [PATCH] libcamera: media_device: prevent sign extension on casts

[Kieran Bingham]

Storing the pointer address of the topology structures using a cast to
__u64 can fail on 32 bit binaries running on a 64 bit kernel due to sign
extension of the pointer.

Convert the casting to use std::uintptr_t which does not sign-extend the value.

Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
---
 src/libcamera/media_device.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/libcamera/media_device.cpp b/src/libcamera/media_device.cpp
index e1ae34f88455..2d493e6c895f 100644
--- a/src/libcamera/media_device.cpp
+++ b/src/libcamera/media_device.cpp
@@ -231,10 +231,10 @@ int MediaDevice::populate()
 	 */
 	while (true) {
 		topology.topology_version = 0;
-		topology.ptr_entities = reinterpret_cast<__u64>(ents);
-		topology.ptr_interfaces = reinterpret_cast<__u64>(interfaces);
-		topology.ptr_links = reinterpret_cast<__u64>(links);
-		topology.ptr_pads = reinterpret_cast<__u64>(pads);
+		topology.ptr_entities = reinterpret_cast<std::uintptr_t>(ents);
+		topology.ptr_interfaces = reinterpret_cast<std::uintptr_t>(interfaces);
+		topology.ptr_links = reinterpret_cast<std::uintptr_t>(links);
+		topology.ptr_pads = reinterpret_cast<std::uintptr_t>(pads);
 
 		ret = ioctl(fd_, MEDIA_IOC_G_TOPOLOGY, &topology);
 		if (ret < 0) {
-- 
2.20.1