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

[ Upstream commit 4beb17e553b49c3dd74505c9f361e756aaae653e ]

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>
Stable-dep-of: fd76e5ccc48f ("net: qrtr: ns: Fix module refcnt")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/qrtr/af_qrtr.c b/net/qrtr/af_qrtr.c
index 71c2295d4a573476ef4665f0747a58a6cf58f9b9..29c0886eb9efe9a8deb87ec4bc9ffdda2477148b 100644 (file)
--- a/net/qrtr/af_qrtr.c
+++ b/net/qrtr/af_qrtr.c
@@ -1279,13 +1279,19 @@ static int __init qrtr_proto_init(void)
                return rc;
 
        rc = sock_register(&qrtr_family);
-       if (rc) {
-               proto_unregister(&qrtr_proto);
-               return rc;
-       }
+       if (rc)
+               goto err_proto;
 
-       qrtr_ns_init();
+       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;
 }
 postcore_initcall(qrtr_proto_init);

diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
index c92dd960bfefa98792d8671d5a1f89f69090f2f7..3376a656da39fcaf9770ae112cd558c61153a874 100644 (file)
--- a/net/qrtr/ns.c
+++ b/net/qrtr/ns.c
@@ -771,7 +771,7 @@ 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;
@@ -782,7 +782,7 @@ 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) {
@@ -815,12 +815,13 @@ 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);
 

diff --git a/net/qrtr/qrtr.h b/net/qrtr/qrtr.h
index dc2b67f17927161e8928c0a5e6a2ad0a44378fdc..3f2d28696062a56201f8774ee50fd1c3daa50708 100644 (file)
--- a/net/qrtr/qrtr.h
+++ b/net/qrtr/qrtr.h
@@ -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);