net: datagram: fix data-races in datagram_poll()

stable inclusion
from stable-v4.19.284
commit 32b304def00874955ce614261d15ea3836aa7947
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7J5UF


CVE: NA

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

[ Upstream commit 5bca1d08 ]

datagram_poll() runs locklessly, we should add READ_ONCE()
annotations while reading sk->sk_err, sk->sk_shutdown and sk->sk_state.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230509173131.3263780-1-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>