tcp: Fix data-races around sysctl_tcp_syn(ack)?_retries.

stable inclusion
from stable-v5.10.188
commit 7b0084918c5f7da21dbb91ec24da7a554edd3209
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8KYFP

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=7b0084918c5f7da21dbb91ec24da7a554edd3209



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[ Upstream commit 20a3b1c0 ]

While reading sysctl_tcp_syn(ack)?_retries, they can be changed
concurrently.  Thus, we need to add READ_ONCE() to their readers.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 3a037f0f ("tcp: annotate data-races around icsk->icsk_syn_retries")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>