tcp_metrics: annotate data-races around tm->tcpm_stamp

stable inclusion
from stable-v4.19.291
commit 754bb55456ea339c37d2aabb35d9c2d549f3c30d
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7ZELT


CVE: NA

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

[ Upstream commit 949ad62a ]

tm->tcpm_stamp can be read or written locklessly.

Add needed READ_ONCE()/WRITE_ONCE() to document this.

Also constify tcpm_check_stamp() dst argument.

Fixes: 51c5d0c4 ("tcp: Maintain dynamic metrics in local cache.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230802131500.1478140-3-edumazet@google.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>