mailbox: mtk-cmdq: Fix local clock ID usage

In the probe function, the clock IDs were pointed to local variables
which should only be used in the same code block, and any access to them
after the probing stage becomes an use-after-free case.

Since there are only limited variants of the gce clock names so far, we
can just declare them as static constants to fix the issue.

Fixes: 85dfdbfc13ea ("mailbox: cmdq: add multi-gce clocks support for mt8195")
Signed-off-by: Fei Shao <fshao@chromium.org>
Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c
index 2f6bb66341e4eb975a62d489b8e09ae31a1c2ff6..a8845b162dbfa0f81845da13d59c1cc4f775bc37 100644 (file)
--- a/drivers/mailbox/mtk-cmdq-mailbox.c
+++ b/drivers/mailbox/mtk-cmdq-mailbox.c
@@ -530,7 +530,8 @@ static int cmdq_probe(struct platform_device *pdev)
        struct device_node *phandle = dev->of_node;
        struct device_node *node;
        int alias_id = 0;
-       char clk_name[4] = "gce";
+       static const char * const clk_name = "gce";
+       static const char * const clk_names[] = { "gce0", "gce1" };
 
        cmdq = devm_kzalloc(dev, sizeof(*cmdq), GFP_KERNEL);
        if (!cmdq)
@@ -567,12 +568,9 @@ static int cmdq_probe(struct platform_device *pdev)
 
        if (cmdq->gce_num > 1) {
                for_each_child_of_node(phandle->parent, node) {
-                       char clk_id[8];
-
                        alias_id = of_alias_get_id(node, clk_name);
                        if (alias_id >= 0 && alias_id < cmdq->gce_num) {
-                               snprintf(clk_id, sizeof(clk_id), "%s%d", clk_name, alias_id);
-                               cmdq->clocks[alias_id].id = clk_id;
+                               cmdq->clocks[alias_id].id = clk_names[alias_id];
                                cmdq->clocks[alias_id].clk = of_clk_get(node, 0);
                                if (IS_ERR(cmdq->clocks[alias_id].clk)) {
                                        dev_err(dev, "failed to get gce clk: %d\n", alias_id);