FAILED: patch "[PATCH] firmware: arm_scpi: Fix string overflow in SCPI genpd driver" failed to apply to 4.9-stable tree

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 865ed67ab955428b9aa771d8b4f1e4fb7fd08945 Mon Sep 17 00:00:00 2001
From: Sudeep Holla <[email protected]>
Date: Thu, 9 Dec 2021 12:04:56 +0000
Subject: [PATCH] firmware: arm_scpi: Fix string overflow in SCPI genpd driver

Without the bound checks for scpi_pd->name, it could result in the buffer overflow when copying the SCPI device name from the corresponding device tree node as the name string is set at maximum size of 30.

Let us fix it by using devm_kasprintf so that the string buffer is allocated dynamically.

index 51201600d789..800673910b51 100644
@@ -16,7 +16,6 @@ struct scpi_pm_domain {
 	struct generic_pm_domain genpd;
 	struct scpi_ops *ops;
 	u32 domain;
-	char name[30];
 };
 
 /*

@@ -110,8 +109,13 @@ static int scpi_pm_domain_probe(struct platform_device *pdev)
 
 		scpi_pd->domain = i;
 		scpi_pd->ops = scpi_ops;
-		sprintf(scpi_pd->name, "%pOFn.%d", np, i);
-		scpi_pd->genpd.name = scpi_pd->name;
+		scpi_pd->genpd.name = devm_kasprintf(dev, GFP_KERNEL,
+						     "%pOFn.%d", np, i);
+		if (!scpi_pd->genpd.name) {
+			dev_err(dev, "Failed to allocate genpd name:%pOFn.%d\n",
+				np, i);
+			continue;
+		}
 		scpi_pd->genpd.power_off = scpi_pd_power_off;
 		scpi_pd->genpd.power_on = scpi_pd_power_on;