[PATCH v8 1/5] soc: qcom: pdr: protect locator_addr with the main mutex

[Dmitry Baryshkov]

If the service locator server is restarted fast enough, the PDR can
rewrite locator_addr fields concurrently. Protect them by placing
modification of those fields under the main pdr->lock.

Fixes: fbe639b44a82 ("soc: qcom: Introduce Protection Domain Restart helpers")
Tested-by: Neil Armstrong <neil.armstr...@linaro.org> # on SM8550-QRD
Tested-by: Steev Klimaszewski <st...@kali.org>
Tested-by: Alexey Minnekhanov <alexey...@postmarketos.org>
Signed-off-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org>
---
 drivers/soc/qcom/pdr_interface.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/soc/qcom/pdr_interface.c b/drivers/soc/qcom/pdr_interface.c
index a1b6a4081dea..e014dd2d8ab3 100644
--- a/drivers/soc/qcom/pdr_interface.c
+++ b/drivers/soc/qcom/pdr_interface.c
@@ -76,12 +76,12 @@ static int pdr_locator_new_server(struct qmi_handle *qmi,
                                              locator_hdl);
        struct pdr_service *pds;
 
+       mutex_lock(&pdr->lock);
        /* Create a local client port for QMI communication */
        pdr->locator_addr.sq_family = AF_QIPCRTR;
        pdr->locator_addr.sq_node = svc->node;
        pdr->locator_addr.sq_port = svc->port;
 
-       mutex_lock(&pdr->lock);
        pdr->locator_init_complete = true;
        mutex_unlock(&pdr->lock);
 
@@ -104,10 +104,10 @@ static void pdr_locator_del_server(struct qmi_handle *qmi,
 
        mutex_lock(&pdr->lock);
        pdr->locator_init_complete = false;
-       mutex_unlock(&pdr->lock);
 
        pdr->locator_addr.sq_node = 0;
        pdr->locator_addr.sq_port = 0;
+       mutex_unlock(&pdr->lock);
 }
 
 static const struct qmi_ops pdr_locator_ops = {
@@ -365,6 +365,7 @@ static int pdr_get_domain_list(struct 
servreg_get_domain_list_req *req,
        if (ret < 0)
                return ret;
 
+       mutex_lock(&pdr->lock);
        ret = qmi_send_request(&pdr->locator_hdl,
                               &pdr->locator_addr,
                               &txn, SERVREG_GET_DOMAIN_LIST_REQ,
@@ -373,15 +374,16 @@ static int pdr_get_domain_list(struct 
servreg_get_domain_list_req *req,
                               req);
        if (ret < 0) {
                qmi_txn_cancel(&txn);
-               return ret;
+               goto err_unlock;
        }
 
        ret = qmi_txn_wait(&txn, 5 * HZ);
        if (ret < 0) {
                pr_err("PDR: %s get domain list txn wait failed: %d\n",
                       req->service_name, ret);
-               return ret;
+               goto err_unlock;
        }
+       mutex_unlock(&pdr->lock);
 
        if (resp->resp.result != QMI_RESULT_SUCCESS_V01) {
                pr_err("PDR: %s get domain list failed: 0x%x\n",
@@ -390,6 +392,11 @@ static int pdr_get_domain_list(struct 
servreg_get_domain_list_req *req,
        }
 
        return 0;
+
+err_unlock:
+       mutex_unlock(&pdr->lock);
+
+       return ret;
 }
 
 static int pdr_locate_service(struct pdr_handle *pdr, struct pdr_service *pds)

-- 
2.39.2