Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Eiichi Tsukata <eiichi.tsukata@nutanix.com>
To:     sgarzare@redhat.com, davem@davemloft.net, kuba@kernel.org,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     Eiichi Tsukata <eiichi.tsukata@nutanix.com>
Subject: [PATCH net] vsock: prevent unnecessary refcnt inc for nonblocking connect
Date:   Sun,  7 Nov 2021 12:03:04 +0000
Message-Id: <20211107120304.38224-1-eiichi.tsukata@nutanix.com>
Content-Type: text/plain
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?tuTMez+XieEExYjgLVcpvj80l6mz2NEwtnRVqzZZmH3xypcj+ZPQZA1uixhY?=
 =?us-ascii?Q?hOsOcqOd51ttFCvgu8VXKecWPknDhBES8TfhXWN/ckXeBEhS2ffor8t3l1ge?=
 =?us-ascii?Q?WApyd1G50QLUj8Nfc5E8bNT2asZLXNl1hhYKWZrTU9bdVKW+Rv+WWIHJpqtI?=
 =?us-ascii?Q?R4wTRp89peBBEHr/4qyX89bM9IG9WYxnjRV2Df2lxIJ3F+QjVhJvD7lJRnDJ?=
 =?us-ascii?Q?tyYkiM7LKX+07qDGpIyB/xDoLGySijIgVNC6fobbn76VhqcP6vKPYiHSefvl?=
 =?us-ascii?Q?fj+MP4I7Y/PH39U1aHMdMwiSx77pllqwTEFXpSpEeTyLQ0wZoAVqXneky4t2?=
 =?us-ascii?Q?i3qzeA1Trput9ABLBPIHfxv71mI7eUIuQBCaPcAxWYOqaknbpiLIRu2viwFN?=
 =?us-ascii?Q?K9iWJ8dX+MmG34UcPLExkXcwZkbsaA0T0vOkH56jXTLFp12+U9DbERxQ3xGV?=
 =?us-ascii?Q?zZtwRGACfZNo10+Mb9b7VIL3hcGQaXy2uyC2ui7zh3x4r3p9EfyYOWmveOc+?=
 =?us-ascii?Q?I0qZJuf796RBfqM48FqPEHTMYe9hbCIxoSQ5LFQ2gC6zx83OrK+H0zoWmDpr?=
 =?us-ascii?Q?4RZh+cZfv716rdZ2R0+A1clWEpv8mYAAoY24M85+U5AHy7mdbB5qOBNniQhp?=
 =?us-ascii?Q?n80cz5wIbogjAoqJ//9fN+9PtgMC4MKbpF1B++aij2tqgJSvOHrBZCkpfPQt?=
 =?us-ascii?Q?BDZZefhigcIUbpfLNUwIYUVaf3Lg8+uPbKYhkZEg7ulB/mWQpA86gudssWNy?=
 =?us-ascii?Q?MKMnnMN8Af1o7aHEhYfhmJ0NSSeBabhZKwZv4m6xXI3AxA4cTboMT8k3EBSq?=
 =?us-ascii?Q?vguvX4P98NNZGZYUxQ/y6R6WC4uXThjCxJuXPMFnVGASWuulESzzaxdR08Q+?=
 =?us-ascii?Q?76C/PLhhRVWgynEygEGxC9QASHrZSsr6sZ5QECTAN6mq0uX8HIiXQC0+Vmr0?=
 =?us-ascii?Q?ge80uS0rBMb6sNyVh+9yG3rQM/8qqHL4Ny6pIL7HI/j8D3PuJAx9w6mfi63u?=
 =?us-ascii?Q?c1GkI+gscCC0EdfP893IXasPV8vX293/5nOGEL7Qneq5qanQUoSV6oyRQ+0x?=
 =?us-ascii?Q?+vngxH2XdXUPKyS9OBxwPV+auE2kdWz0T78HXetNy8+i7Q/q+NyTHX/MRfzy?=
 =?us-ascii?Q?CBgcz2qlT5k3/38lZfNAZju8e+FPEYStSmTWZUXEsVH6kBkJ6V0alhrM2Z0M?=
 =?us-ascii?Q?2Eu+MLsw7RXu85OtwVA8//Pb/+nROca6UiAnWYwsvvlgeSWMVoEkCksmtbra?=
 =?us-ascii?Q?CNVtBInX/p6iDecIQV/GAv6HmX0HmQFKO/HT/abkSjjTv0pIhDMSjj/C5wa6?=
 =?us-ascii?Q?AZv8//P7icX2FAsmkHF5Paclo1a9BmNhvSe0jZ8ZUmvV0UMgf5cmN/BGmEym?=
 =?us-ascii?Q?W0V0akdSsjEO5NluOQKUlcdRFoVqZgIktKIDG+N7utCK5pWvs5BmFqD4/9v+?=
 =?us-ascii?Q?mQDTO/tM4ebqWmuR4Fqmj3u8UW9gBdTjNcMKmn1ANw6MLzeK40MRQ87HBkN9?=
 =?us-ascii?Q?t1YUxwHDw9Yt58t9UAkbef3TxeqkOr84+FTcqeRg0XIvYyt27YNETUT3DgmY?=
 =?us-ascii?Q?uA4Lm2vStMkp5nyKkJLVXe9pM5zJrIrbfrN/3Jw7kXy7gRDtSiGzz8atyJWd?=
 =?us-ascii?Q?pkt9Mz2IZtMH/4bOpMr78h21lmp2HYn9H8o7P+VhnNE+/G/Av8iJiTsDwvuC?=
 =?us-ascii?Q?4OfcNy+F6FiPXX9E9EMMgilVkKs=3D?=
X-OriginatorOrg: nutanix.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 7386f9ba-e045-41bf-d579-08d9a1e6c51a
X-MS-Exchange-CrossTenant-AuthSource: CH0PR02MB8041.namprd02.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Nov 2021 12:04:37.3206
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: bb047546-786f-4de1-bd75-24e5b6f79043
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: rvFZdYMACGMhBAXiD4yyJtxEn+lxY2w6m8F8+dlnwbLAHPgT7pbSewlqmFvbCkPGFhErokjNGHXlFWMfRXyWZZKGoipf6J0fFII0h5gn8tY=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR02MB7046
X-Proofpoint-GUID: KShWEJux4iNfJbuCtbg0YSuyL4ze5pg7
X-Proofpoint-ORIG-GUID: KShWEJux4iNfJbuCtbg0YSuyL4ze5pg7
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.0.607.475
 definitions=2021-11-07_06,2021-11-03_01,2020-04-07_01
X-Proofpoint-Spam-Reason: safe
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Currently vosck_connect() increments sock refcount for nonblocking
socket each time it's called, which can lead to memory leak if
it's called multiple times because connect timeout function decrements
sock refcount only once.

Fixes it by making vsock_connect() return -EALREADY immediately when
sock state is already SS_CONNECTING.

Signed-off-by: Eiichi Tsukata <eiichi.tsukata@nutanix.com>
---
 net/vmw_vsock/af_vsock.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 7d851eb3a683..ed0df839c38c 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1322,6 +1322,8 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
 		 * non-blocking call.
 		 */
 		err = -EALREADY;
+		if (flags & O_NONBLOCK)
+			goto out;
 		break;
 	default:
 		if ((sk->sk_state == TCP_LISTEN) ||
-- 
2.33.1