commit 8bf5967d1ed9094cd68447b1b2e11070ddd885b9
author Maciej Żenczykowski <maze@google.com> Tue Jan 17 23:52:02 2023 +0000
committer Maciej Żenczykowski <maze@google.com> Mon Jan 30 19:31:27 2023 +0000
tree c6bf96ed382263f2d1b90fce3ba5953345d67270
parent b5cfb6426cfba47c6ee37cc1836678373e9eb347

clat: just always set mark unconditionally, part 2

Setting SO_MARK to MARK_UNSET, ie. 0, is harmless,
since the default for a brand new socket is already 0.

See ClatCoordinator.java getFwMark() for the mark we actually pass in,
which is guaranteed to have at least 4 bits (16,17,18,19) set.

See also:
  https://android-review.git.corp.google.com/c/platform/packages/modules/Connectivity/+/2392272

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I3b4eebc0a5ad20390a13efcc58cecf94868686ba

service/native/libs/libclat/clatutils.cpp

diff --git a/service/native/libs/libclat/clatutils.cpp b/service/native/libs/libclat/clatutils.cpp
index 64e5b91..c6a9781 100644
--- a/service/native/libs/libclat/clatutils.cpp
+++ b/service/native/libs/libclat/clatutils.cpp
@@ -29,9 +29,6 @@
 #include "checksum.h"
 }
 
-// Sync from system/netd/include/netid_client.h.
-#define MARK_UNSET 0u
-
 namespace android {
 namespace net {
 namespace clat {
@@ -128,7 +125,7 @@
 
     // Socket's mark affects routing decisions (network selection)
     // An fwmark is necessary for clat to bypass the VPN during initialization.
-    if ((mark != MARK_UNSET) && setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
+    if (setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
         int ret = errno;
         ALOGE("setsockopt(SOL_SOCKET, SO_MARK) failed: %s", strerror(errno));
         close(s);
@@ -176,7 +173,7 @@
     }
 
     // Socket's mark affects routing decisions (network selection)
-    if ((mark != MARK_UNSET) && setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
+    if (setsockopt(s, SOL_SOCKET, SO_MARK, &mark, sizeof(mark))) {
         int ret = errno;
         ALOGE("setsockopt(SOL_SOCKET, SO_MARK) failed: %s", strerror(errno));
         close(s);