From 1c24285372412b26af4f0f980c115e857fb87c02 Mon Sep 17 00:00:00 2001
From: Guoqing Jiang <gqjiang@suse.com>
Date: Mon, 7 Aug 2017 14:31:20 +0800
Subject: [PATCH] dlm: use sock_create_lite inside tcp_accept_from_sock
Git-commit: 1c24285372412b26af4f0f980c115e857fb87c02
Patch-mainline: v4.14-rc1
References: bsc#1069364
With commit 0ffdaf5b41cf ("net/sock: add WARN_ON(parent->sk)
in sock_graft()"), a calltrace happened as follows:
[ 457.018340] WARNING: CPU: 0 PID: 15623 at ./include/net/sock.h:1703 inet_accept+0x135/0x140
...
[ 457.018381] RIP: 0010:inet_accept+0x135/0x140
[ 457.018381] RSP: 0018:ffffc90001727d18 EFLAGS: 00010286
[ 457.018383] RAX: 0000000000000001 RBX: ffff880012413000 RCX: 0000000000000001
[ 457.018384] RDX: 000000000000018a RSI: 00000000fffffe01 RDI: ffffffff8156fae8
[ 457.018384] RBP: ffffc90001727d38 R08: 0000000000000000 R09: 0000000000004305
[ 457.018385] R10: 0000000000000001 R11: 0000000000004304 R12: ffff880035ae7a00
[ 457.018386] R13: ffff88001282af10 R14: ffff880034e4e200 R15: 0000000000000000
[ 457.018387] FS: 0000000000000000(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
[ 457.018388] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 457.018389] CR2: 00007fdec22f9000 CR3: 0000000002b5a000 CR4: 00000000000006f0
[ 457.018395] Call Trace:
[ 457.018402] tcp_accept_from_sock.part.8+0x12d/0x449 [dlm]
[ 457.018405] ? vprintk_emit+0x248/0x2d0
[ 457.018409] tcp_accept_from_sock+0x3f/0x50 [dlm]
[ 457.018413] process_recv_sockets+0x3b/0x50 [dlm]
[ 457.018415] process_one_work+0x138/0x370
[ 457.018417] worker_thread+0x4d/0x3b0
[ 457.018419] kthread+0x109/0x140
[ 457.018421] ? rescuer_thread+0x320/0x320
[ 457.018422] ? kthread_park+0x60/0x60
[ 457.018424] ret_from_fork+0x25/0x30
Since newsocket created by sock_create_kern sets it's
sock by the path:
sock_create_kern -> __sock_creat
->pf->create => inet_create
-> sock_init_data
Then WARN_ON is triggered by "con->sock->ops->accept =>
inet_accept -> sock_graft", it also means newsock->sk
is leaked since sock_graft will replace it with a new
sk.
To resolve the issue, we need to use sock_create_lite
instead of sock_create_kern, like commit 0933a578cd55
("rds: tcp: use sock_create_lite() to create the accept
socket") did.
Reported-by: Zhilong Liu <zlliu@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>
---
fs/dlm/lowcomms.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 9382db9..4813d0e 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -729,7 +729,7 @@ static int tcp_accept_from_sock(struct connection *con)
mutex_unlock(&connections_lock);
memset(&peeraddr, 0, sizeof(peeraddr));
- result = sock_create_kern(&init_net, dlm_local_addr[0]->ss_family,
+ result = sock_create_lite(dlm_local_addr[0]->ss_family,
SOCK_STREAM, IPPROTO_TCP, &newsock);
if (result < 0)
return -ENOMEM;
--
1.8.5.6