net: qrtr: fix null-ptr-deref in qrtr_ns_remove

A null-ptr-deref bug is reported by Hulk Robot like this:
--------------
KASAN: null-ptr-deref in range [0x0000000000000128-0x000000000000012f]
Call Trace:
qrtr_ns_remove+0x22/0x40 [ns]
qrtr_proto_fini+0xa/0x31 [qrtr]
__x64_sys_delete_module+0x337/0x4e0
do_syscall_64+0x34/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x468ded
--------------

When qrtr_ns_init fails in qrtr_proto_init, qrtr_ns_remove which would
be called later on would raise a null-ptr-deref because qrtr_ns.workqueue
has been destroyed.

Fix it by making qrtr_ns_init have a return value and adding a check in
qrtr_proto_init.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Qinglang Miao 2021-01-05 13:57:54 +08:00 committed by David S. Miller
parent 7a68d725e4
commit 4beb17e553
3 changed files with 16 additions and 9 deletions

View File

@ -755,7 +755,7 @@ static void qrtr_ns_data_ready(struct sock *sk)
queue_work(qrtr_ns.workqueue, &qrtr_ns.work);
}
void qrtr_ns_init(void)
int qrtr_ns_init(void)
{
struct sockaddr_qrtr sq;
int ret;
@ -766,7 +766,7 @@ void qrtr_ns_init(void)
ret = sock_create_kern(&init_net, AF_QIPCRTR, SOCK_DGRAM,
PF_QIPCRTR, &qrtr_ns.sock);
if (ret < 0)
return;
return ret;
ret = kernel_getsockname(qrtr_ns.sock, (struct sockaddr *)&sq);
if (ret < 0) {
@ -797,12 +797,13 @@ void qrtr_ns_init(void)
if (ret < 0)
goto err_wq;
return;
return 0;
err_wq:
destroy_workqueue(qrtr_ns.workqueue);
err_sock:
sock_release(qrtr_ns.sock);
return ret;
}
EXPORT_SYMBOL_GPL(qrtr_ns_init);

View File

@ -1287,15 +1287,21 @@ static int __init qrtr_proto_init(void)
return rc;
rc = sock_register(&qrtr_family);
if (rc) {
if (rc)
goto err_proto;
rc = qrtr_ns_init();
if (rc)
goto err_sock;
return 0;
err_sock:
sock_unregister(qrtr_family.family);
err_proto:
proto_unregister(&qrtr_proto);
return rc;
}
qrtr_ns_init();
return rc;
}
postcore_initcall(qrtr_proto_init);
static void __exit qrtr_proto_fini(void)

View File

@ -29,7 +29,7 @@ void qrtr_endpoint_unregister(struct qrtr_endpoint *ep);
int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len);
void qrtr_ns_init(void);
int qrtr_ns_init(void);
void qrtr_ns_remove(void);