phonet: refcount leak in pep_sock_accep

mainline inclusion
from mainline-v5.16-rc6
commit bcd0f933
category: bugfix
bugzilla: 185940 https://gitee.com/openeuler/kernel/issues/I4DDEL
CVE: CVE-2021-45095

Reference: https://patchwork.kernel.org/project/netdevbpf/patch/20211209082839.33985-1-hbh25y@gmail.com/



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

sock_hold(sk) is invoked in pep_sock_accept(), but __sock_put(sk) is not
invoked in subsequent failure branches(pep_accept_conn() != 0).

Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Link: https://lore.kernel.org/r/20211209082839.33985-1-hbh25y@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Huang Guobin <huangguobin4@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>