tcp: annotate data races around tp->mtu_info

stable inclusion
from stable-5.10.53
commit d60f07bcb76f0f2f0c786a669260d31d74d6a9ba
bugzilla: 175574 https://gitee.com/openeuler/kernel/issues/I4DTUX

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d60f07bcb76f0f2f0c786a669260d31d74d6a9ba



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

commit 561022ac upstream.

While tp->mtu_info is read while socket is owned, the write
sides happen from err handlers (tcp_v[46]_mtu_reduced)
which only own the socket spinlock.

Fixes: 563d34d0 ("tcp: dont drop MTU reduction indications")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Acked-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>