stable inclusion
from stable-v5.10.134
commit 0dc2f19d8c2636cebda7976b5ea40c6d69f0d891
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5ZVR7

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0dc2f19d8c2636cebda7976b5ea40c6d69f0d891

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

[ Upstream commit 021266ec ]

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

Fixes: cf1ef3f0 ("net/tcp_fastopen: Disable active side TFO in certain scenarios")
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>