On Fri, Jun 25, 2021 at 01:33:38AM -0700, menglong8.dong@xxxxxxxxx wrote: > From: Yang Yang <yang.yang29@xxxxxxxxxx> > > With user namespace enabled, root in container can't modify > /proc/sys/net/ipv4/ip_forward. While /proc/sys/net/ipv4/ip_forward > belongs to root and mode is 644. Since root in container may > be non-root in host, but test_perm() doesn't consider about it. I'm confused about what the actual problem is tbh: root@h3:~# stat -c "%A %a %n" /proc/sys/net/ipv4/ip_forward -rw-r--r-- 644 /proc/sys/net/ipv4/ip_forward root@h3:~# echo 0 > /proc/sys/net/ipv4/ip_forward root@h3:~# cat /proc/sys/net/ipv4/ip_forward 0 root@h3:~# cat /proc/self/uid_map 0 100000 1000000000 Also, this patch changes the security requirements for all sysctls which is unfortunately unacceptable.