stable inclusion
from stable-v5.10.140
commit 371a3bcf3144584c511f80e87d4c28ac2c75e9a7
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I63FTT

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=371a3bcf3144584c511f80e87d4c28ac2c75e9a7

--------------------------------

[ Upstream commit af67508e ]

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

Fixes: 79134e6c ("net: do not create fallback tunnels for non-default namespaces")
Signed-off-by: NKuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>