iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

vhost/vsock: Fix error handling in vhost_vsock_init()

Browse Source 
[ Upstream commit 7a4efe182ca61fb3e5307e69b261c57cbf434cd4 ]

A problem about modprobe vhost_vsock failed is triggered with the
following log given:

modprobe: ERROR: could not insert 'vhost_vsock': Device or resource busy

The reason is that vhost_vsock_init() returns misc_register() directly
without checking its return value, if misc_register() failed, it returns
without calling vsock_core_unregister() on vhost_transport, resulting the
vhost_vsock can never be installed later.
A simple call graph is shown as below:

 vhost_vsock_init()
   vsock_core_register() # register vhost_transport
   misc_register()
     device_create_with_groups()
       device_create_groups_vargs()
         dev = kzalloc(...) # OOM happened
   # return without unregister vhost_transport

Fix by calling vsock_core_unregister() when misc_register() returns error.

Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Message-Id: <20221108101705.45981-1-yuancan@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Yuan Can 2022-11-08 10:17:05 +00:00 committed by Greg Kroah-Hartman
parent e0f5c962c0
commit eabb3ceb04
1 changed files with 8 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/vhost/vsock.c
View File

@ -854,7 +854,14 @@ static int __init vhost_vsock_init(void)
VSOCK_TRANSPORT_F_H2G);
if (ret < 0)
return ret;
return misc_register(&vhost_vsock_misc);
ret = misc_register(&vhost_vsock_misc);
if (ret) {
vsock_core_unregister(&vhost_transport.transport);
return ret;
}
return 0;
};
static void __exit vhost_vsock_exit(void)