From c7355827b27c550824bbcc1f0586cf993bf83d94 Mon Sep 17 00:00:00 2001
From: "tsutomu.owa@toshiba.co.jp" <tsutomu.owa@toshiba.co.jp>
Date: Tue, 12 Sep 2017 08:56:00 +0000
Subject: [PATCH 07/19] DLM: fix to use sock_mutex correctly in
xxx_accept_from_sock
Git-commit: c7355827b27c550824bbcc1f0586cf993bf83d94
Patch-mainline: v4.15-rc1
References: bsc#1074590
In the current implementation, we think that exclusion control
for othercon in tcp_accept_from_sock() and sctp_accept_from_sock()
was not enough. We fix them.
Signed-off-by: Tadashi Miyauchi <miyauchi@toshiba-tops.co.jp>
Signed-off-by: Tsutomu Owa <tsutomu.owa@toshiba.co.jp>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Gang He <ghe@suse.com>
---
fs/dlm/lowcomms.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 420946d..b275813 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -801,16 +801,19 @@ static int tcp_accept_from_sock(struct connection *con)
INIT_WORK(&othercon->rwork, process_recv_sockets);
set_bit(CF_IS_OTHERCON, &othercon->flags);
}
+ mutex_lock_nested(&othercon->sock_mutex, 2);
if (!othercon->sock) {
newcon->othercon = othercon;
othercon->sock = newsock;
newsock->sk->sk_user_data = othercon;
add_sock(newsock, othercon);
addcon = othercon;
+ mutex_unlock(&othercon->sock_mutex);
}
else {
printk("Extra connection from node %d attempted\n", nodeid);
result = -EAGAIN;
+ mutex_unlock(&othercon->sock_mutex);
mutex_unlock(&newcon->sock_mutex);
goto accept_err;
}
@@ -918,15 +921,18 @@ static int sctp_accept_from_sock(struct connection *con)
INIT_WORK(&othercon->rwork, process_recv_sockets);
set_bit(CF_IS_OTHERCON, &othercon->flags);
}
+ mutex_lock_nested(&othercon->sock_mutex, 2);
if (!othercon->sock) {
newcon->othercon = othercon;
othercon->sock = newsock;
newsock->sk->sk_user_data = othercon;
add_sock(newsock, othercon);
addcon = othercon;
+ mutex_unlock(&othercon->sock_mutex);
} else {
printk("Extra connection from node %d attempted\n", nodeid);
ret = -EAGAIN;
+ mutex_unlock(&othercon->sock_mutex);
mutex_unlock(&newcon->sock_mutex);
goto accept_err;
}
--
1.8.5.6