[PATCH] net: qrtr: Allocate workqueue before kernel_bind

[PATCH] net: qrtr: Allocate workqueue before kernel_bind

[Chris Lew]

A null pointer dereference in qrtr_ns_data_ready() is seen if a client
opens a qrtr socket before qrtr_ns_init() can bind to the control port.
When the control port is bound, the ENETRESET error will be broadcasted
and clients will close their sockets. This results in DEL_CLIENT
packets being sent to the ns and qrtr_ns_data_ready() being called
without the workqueue being allocated.

Allocate the workqueue before setting sk_data_ready and binding to the
control port. This ensures that the work and workqueue structs are
allocated and initialized before qrtr_ns_data_ready can be called.

Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
Signed-off-by: Chris Lew <clew@codeaurora.org>
---
 net/qrtr/ns.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
index e7d0fe3f4330..c5b3202a14ca 100644
--- a/net/qrtr/ns.c
+++ b/net/qrtr/ns.c
@@ -712,6 +712,10 @@ void qrtr_ns_init(void)
 		goto err_sock;
 	}
 
+	qrtr_ns.workqueue = alloc_workqueue("qrtr_ns_handler", WQ_UNBOUND, 1);
+	if (!qrtr_ns.workqueue)
+		goto err_sock;
+
 	qrtr_ns.sock->sk->sk_data_ready = qrtr_ns_data_ready;
 
 	sq.sq_port = QRTR_PORT_CTRL;
@@ -720,17 +724,13 @@ void qrtr_ns_init(void)
 	ret = kernel_bind(qrtr_ns.sock, (struct sockaddr *)&sq, sizeof(sq));
 	if (ret < 0) {
 		pr_err("failed to bind to socket\n");
-		goto err_sock;
+		goto err_wq;
 	}
 
 	qrtr_ns.bcast_sq.sq_family = AF_QIPCRTR;
 	qrtr_ns.bcast_sq.sq_node = QRTR_NODE_BCAST;
 	qrtr_ns.bcast_sq.sq_port = QRTR_PORT_CTRL;
 
-	qrtr_ns.workqueue = alloc_workqueue("qrtr_ns_handler", WQ_UNBOUND, 1);
-	if (!qrtr_ns.workqueue)
-		goto err_sock;
-
 	ret = say_hello(&qrtr_ns.bcast_sq);
 	if (ret < 0)
 		goto err_wq;
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH] net: qrtr: Allocate workqueue before kernel_bind

[Bjorn Andersson]

On Thu 28 May 16:05 PDT 2020, Chris Lew wrote:

> A null pointer dereference in qrtr_ns_data_ready() is seen if a client
> opens a qrtr socket before qrtr_ns_init() can bind to the control port.
> When the control port is bound, the ENETRESET error will be broadcasted
> and clients will close their sockets. This results in DEL_CLIENT
> packets being sent to the ns and qrtr_ns_data_ready() being called
> without the workqueue being allocated.
> 
> Allocate the workqueue before setting sk_data_ready and binding to the
> control port. This ensures that the work and workqueue structs are
> allocated and initialized before qrtr_ns_data_ready can be called.
> 

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
> Signed-off-by: Chris Lew <clew@codeaurora.org>
> ---
>  net/qrtr/ns.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> index e7d0fe3f4330..c5b3202a14ca 100644
> --- a/net/qrtr/ns.c
> +++ b/net/qrtr/ns.c
> @@ -712,6 +712,10 @@ void qrtr_ns_init(void)
>  		goto err_sock;
>  	}
>  
> +	qrtr_ns.workqueue = alloc_workqueue("qrtr_ns_handler", WQ_UNBOUND, 1);
> +	if (!qrtr_ns.workqueue)
> +		goto err_sock;
> +
>  	qrtr_ns.sock->sk->sk_data_ready = qrtr_ns_data_ready;
>  
>  	sq.sq_port = QRTR_PORT_CTRL;
> @@ -720,17 +724,13 @@ void qrtr_ns_init(void)
>  	ret = kernel_bind(qrtr_ns.sock, (struct sockaddr *)&sq, sizeof(sq));
>  	if (ret < 0) {
>  		pr_err("failed to bind to socket\n");
> -		goto err_sock;
> +		goto err_wq;
>  	}
>  
>  	qrtr_ns.bcast_sq.sq_family = AF_QIPCRTR;
>  	qrtr_ns.bcast_sq.sq_node = QRTR_NODE_BCAST;
>  	qrtr_ns.bcast_sq.sq_port = QRTR_PORT_CTRL;
>  
> -	qrtr_ns.workqueue = alloc_workqueue("qrtr_ns_handler", WQ_UNBOUND, 1);
> -	if (!qrtr_ns.workqueue)
> -		goto err_sock;
> -
>  	ret = say_hello(&qrtr_ns.bcast_sq);
>  	if (ret < 0)
>  		goto err_wq;
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
> 

Re: [PATCH] net: qrtr: Allocate workqueue before kernel_bind

[Manivannan Sadhasivam]

On Thu, May 28, 2020 at 04:05:26PM -0700, Chris Lew wrote:
> A null pointer dereference in qrtr_ns_data_ready() is seen if a client
> opens a qrtr socket before qrtr_ns_init() can bind to the control port.
> When the control port is bound, the ENETRESET error will be broadcasted
> and clients will close their sockets. This results in DEL_CLIENT
> packets being sent to the ns and qrtr_ns_data_ready() being called
> without the workqueue being allocated.
> 
> Allocate the workqueue before setting sk_data_ready and binding to the
> control port. This ensures that the work and workqueue structs are
> allocated and initialized before qrtr_ns_data_ready can be called.
> 
> Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
> Signed-off-by: Chris Lew <clew@codeaurora.org>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Thanks,
Mani

> ---
>  net/qrtr/ns.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> index e7d0fe3f4330..c5b3202a14ca 100644
> --- a/net/qrtr/ns.c
> +++ b/net/qrtr/ns.c
> @@ -712,6 +712,10 @@ void qrtr_ns_init(void)
>  		goto err_sock;
>  	}
>  
> +	qrtr_ns.workqueue = alloc_workqueue("qrtr_ns_handler", WQ_UNBOUND, 1);
> +	if (!qrtr_ns.workqueue)
> +		goto err_sock;
> +
>  	qrtr_ns.sock->sk->sk_data_ready = qrtr_ns_data_ready;
>  
>  	sq.sq_port = QRTR_PORT_CTRL;
> @@ -720,17 +724,13 @@ void qrtr_ns_init(void)
>  	ret = kernel_bind(qrtr_ns.sock, (struct sockaddr *)&sq, sizeof(sq));
>  	if (ret < 0) {
>  		pr_err("failed to bind to socket\n");
> -		goto err_sock;
> +		goto err_wq;
>  	}
>  
>  	qrtr_ns.bcast_sq.sq_family = AF_QIPCRTR;
>  	qrtr_ns.bcast_sq.sq_node = QRTR_NODE_BCAST;
>  	qrtr_ns.bcast_sq.sq_port = QRTR_PORT_CTRL;
>  
> -	qrtr_ns.workqueue = alloc_workqueue("qrtr_ns_handler", WQ_UNBOUND, 1);
> -	if (!qrtr_ns.workqueue)
> -		goto err_sock;
> -
>  	ret = say_hello(&qrtr_ns.bcast_sq);
>  	if (ret < 0)
>  		goto err_wq;
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
> 

Re: [PATCH] net: qrtr: Allocate workqueue before kernel_bind

[David Miller]

From: Chris Lew <clew@codeaurora.org>
Date: Thu, 28 May 2020 16:05:26 -0700

> A null pointer dereference in qrtr_ns_data_ready() is seen if a client
> opens a qrtr socket before qrtr_ns_init() can bind to the control port.
> When the control port is bound, the ENETRESET error will be broadcasted
> and clients will close their sockets. This results in DEL_CLIENT
> packets being sent to the ns and qrtr_ns_data_ready() being called
> without the workqueue being allocated.
> 
> Allocate the workqueue before setting sk_data_ready and binding to the
> control port. This ensures that the work and workqueue structs are
> allocated and initialized before qrtr_ns_data_ready can be called.
> 
> Fixes: 0c2204a4ad71 ("net: qrtr: Migrate nameservice to kernel from userspace")
> Signed-off-by: Chris Lew <clew@codeaurora.org>

Applied, thank you.