commit 0781d40df151373d4d8039104963da38c75b2a61
author Hugo Benichi <hugobenichi@google.com> Mon Feb 22 13:43:11 2021 +0900
committer Commit Bot <commit-bot@chromium.org> Mon Mar 08 07:21:02 2021 +0000
tree 1bc92b7b0a08dfcbabc48ad72184386efd25094c
parent 4c19c92943e90bb2e525de02248f0fb7985ec16d

patchpanel: directly use chown() syscall

After:
localhost ~ # ls -ld /sys/class/xt_idletimer
drwxr-xr-x. 2 android-root android-root 0 Mar  5 13:19 /sys/class/xt_idletimer
localhost ~ # android-sh -c "ls -ld /sys/class/xt_idletimer"
drwxr-xr-x 2 root root 0 2021-03-05 13:19 /sys/class/xt_idletimer

Also refactor ScopedNS to support both CLONE_NEWNET and CLONE_NEWNS.

BUG=b:178980566
TEST=Compiled, flashed patchpanel on rammus, started ARC container,
checked that /sys/class/xt_idletimer owner shows as android_root on the
host (xt_idletimer is not namespaced), check /sys/class/xt_idletimer
owner shows as root inside ARC.

Change-Id: Ia799dda263da996fa4880e1cf676556845e7f622
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/2738497
Reviewed-by: Garrick Evans <garrick@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Hugo Benichi <hugobenichi@google.com>
Commit-Queue: Hugo Benichi <hugobenichi@google.com>

patchpanel/datapath.cc

diff --git a/patchpanel/datapath.cc b/patchpanel/datapath.cc
index 4595459..1bb62c1 100644
--- a/patchpanel/datapath.cc
+++ b/patchpanel/datapath.cc
@@ -487,7 +487,7 @@
 
   // Configure the remote veth in namespace |netns_name|.
   {
-    ScopedNS ns(netns_pid);
+    ScopedNS ns(netns_pid, ScopedNS::Type::Network);
     if (!ns.IsValid() && netns_pid != kTestPID) {
       LOG(ERROR)
           << "Cannot create virtual link -- invalid container namespace?";
@@ -604,7 +604,7 @@
   }
 
   {
-    ScopedNS ns(nsinfo.pid);
+    ScopedNS ns(nsinfo.pid, ScopedNS::Type::Network);
     if (!ns.IsValid() && nsinfo.pid != kTestPID) {
       LOG(ERROR) << "Invalid namespace pid " << nsinfo.pid;
       RemoveInterface(nsinfo.host_ifname);