[PATCH] drivers/soc: Remove all strcpy() uses in favor of strscpy()

[Len Baker <len.baker@gmx.com>]

strcpy() performs no bounds checking on the destination buffer. This
could result in linear overflows beyond the end of the buffer, leading
to all kinds of misbehaviors. The safe replacement is strscpy().

Signed-off-by: Len Baker <len.baker@gmx.com>
---
This is a task of the KSPP [1]

[1] https://github.com/KSPP/linux/issues/88

 drivers/soc/qcom/pdr_interface.c    | 13 +++++++------
 drivers/soc/renesas/r8a779a0-sysc.c |  6 ++++--
 drivers/soc/renesas/rcar-sysc.c     |  6 ++++--
 drivers/soc/ti/knav_dma.c           |  2 +-
 4 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/drivers/soc/qcom/pdr_interface.c b/drivers/soc/qcom/pdr_interface.c
index 915d5bc3d46e..cf119fde749d 100644
--- a/drivers/soc/qcom/pdr_interface.c
+++ b/drivers/soc/qcom/pdr_interface.c
@@ -131,7 +131,7 @@ static int pdr_register_listener(struct pdr_handle *pdr,
 		return ret;

 	req.enable = enable;
-	strcpy(req.service_path, pds->service_path);
+	strscpy(req.service_path, pds->service_path, sizeof(req.service_path));

 	ret = qmi_send_request(&pdr->notifier_hdl, &pds->addr,
 			       &txn, SERVREG_REGISTER_LISTENER_REQ,
@@ -257,7 +257,7 @@ static int pdr_send_indack_msg(struct pdr_handle *pdr, struct pdr_service *pds,
 		return ret;

 	req.transaction_id = tid;
-	strcpy(req.service_path, pds->service_path);
+	strscpy(req.service_path, pds->service_path, sizeof(req.service_path));

 	ret = qmi_send_request(&pdr->notifier_hdl, &pds->addr,
 			       &txn, SERVREG_SET_ACK_REQ,
@@ -406,7 +406,7 @@ static int pdr_locate_service(struct pdr_handle *pdr, struct pdr_service *pds)
 		return -ENOMEM;

 	/* Prepare req message */
-	strcpy(req.service_name, pds->service_name);
+	strscpy(req.service_name, pds->service_name, sizeof(req.service_name));
 	req.domain_offset_valid = true;
 	req.domain_offset = 0;

@@ -531,8 +531,8 @@ struct pdr_service *pdr_add_lookup(struct pdr_handle *pdr,
 		return ERR_PTR(-ENOMEM);

 	pds->service = SERVREG_NOTIFIER_SERVICE;
-	strcpy(pds->service_name, service_name);
-	strcpy(pds->service_path, service_path);
+	strscpy(pds->service_name, service_name, sizeof(pds->service_name));
+	strscpy(pds->service_path, service_path, sizeof(pds->service_path));
 	pds->need_locator_lookup = true;

 	mutex_lock(&pdr->list_lock);
@@ -587,7 +587,8 @@ int pdr_restart_pd(struct pdr_handle *pdr, struct pdr_service *pds)
 			break;

 		/* Prepare req message */
-		strcpy(req.service_path, pds->service_path);
+		strscpy(req.service_path, pds->service_path,
+			sizeof(req.service_path));
 		addr = pds->addr;
 		break;
 	}
diff --git a/drivers/soc/renesas/r8a779a0-sysc.c b/drivers/soc/renesas/r8a779a0-sysc.c
index d464ffa1be33..25f8164b96d0 100644
--- a/drivers/soc/renesas/r8a779a0-sysc.c
+++ b/drivers/soc/renesas/r8a779a0-sysc.c
@@ -404,19 +404,21 @@ static int __init r8a779a0_sysc_pd_init(void)
 	for (i = 0; i < info->num_areas; i++) {
 		const struct r8a779a0_sysc_area *area = &info->areas[i];
 		struct r8a779a0_sysc_pd *pd;
+		size_t area_name_size;

 		if (!area->name) {
 			/* Skip NULLified area */
 			continue;
 		}

-		pd = kzalloc(sizeof(*pd) + strlen(area->name) + 1, GFP_KERNEL);
+		area_name_size = strlen(area->name) + 1;
+		pd = kzalloc(sizeof(*pd) + area_name_size, GFP_KERNEL);
 		if (!pd) {
 			error = -ENOMEM;
 			goto out_put;
 		}

-		strcpy(pd->name, area->name);
+		strscpy(pd->name, area->name, area_name_size);
 		pd->genpd.name = pd->name;
 		pd->pdr = area->pdr;
 		pd->flags = area->flags;
diff --git a/drivers/soc/renesas/rcar-sysc.c b/drivers/soc/renesas/rcar-sysc.c
index 53387a72ca00..0eae5ce0eeb0 100644
--- a/drivers/soc/renesas/rcar-sysc.c
+++ b/drivers/soc/renesas/rcar-sysc.c
@@ -396,19 +396,21 @@ static int __init rcar_sysc_pd_init(void)
 	for (i = 0; i < info->num_areas; i++) {
 		const struct rcar_sysc_area *area = &info->areas[i];
 		struct rcar_sysc_pd *pd;
+		size_t area_name_size;

 		if (!area->name) {
 			/* Skip NULLified area */
 			continue;
 		}

-		pd = kzalloc(sizeof(*pd) + strlen(area->name) + 1, GFP_KERNEL);
+		area_name_size = strlen(area->name) + 1;
+		pd = kzalloc(sizeof(*pd) + area_name_size, GFP_KERNEL);
 		if (!pd) {
 			error = -ENOMEM;
 			goto out_put;
 		}

-		strcpy(pd->name, area->name);
+		strscpy(pd->name, area->name, area_name_size);
 		pd->genpd.name = pd->name;
 		pd->ch.chan_offs = area->chan_offs;
 		pd->ch.chan_bit = area->chan_bit;
diff --git a/drivers/soc/ti/knav_dma.c b/drivers/soc/ti/knav_dma.c
index 591d14ebcb11..5f9816d317a5 100644
--- a/drivers/soc/ti/knav_dma.c
+++ b/drivers/soc/ti/knav_dma.c
@@ -691,7 +691,7 @@ static int dma_init(struct device_node *cloud, struct device_node *dma_node)
 	dma->max_rx_flow = max_rx_flow;
 	dma->max_tx_chan = min(max_tx_chan, max_tx_sched);
 	atomic_set(&dma->ref_count, 0);
-	strcpy(dma->name, node->name);
+	strscpy(dma->name, node->name, sizeof(dma->name));
 	spin_lock_init(&dma->lock);

 	for (i = 0; i < dma->max_tx_chan; i++) {
--
2.25.1