ip: Fix a data-race around sysctl_fwmark_reflect.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2149949


Upstream Status: linux.git

commit 85d0b4db
Author: Kuniyuki Iwashima <kuniyu@amazon.com>
Date:   Wed Jul 13 13:51:57 2022 -0700

    ip: Fix a data-race around sysctl_fwmark_reflect.

    While reading sysctl_fwmark_reflect, it can be changed concurrently.
    Thus, we need to add READ_ONCE() to its reader.

    Fixes: e110861f ("net: add a sysctl to reflect the fwmark on replies")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Guillaume Nault <gnault@redhat.com>