From 865ed67ab955428b9aa771d8b4f1e4fb7fd08945 Mon Sep 17 00:00:00 2001
From: Sudeep Holla <sudeep.holla@arm.com>
Date: Thu, 9 Dec 2021 12:04:56 +0000
Subject: [PATCH] firmware: arm_scpi: Fix string overflow in SCPI genpd driver
Git-commit: 865ed67ab955428b9aa771d8b4f1e4fb7fd08945
Patch-mainline: v5.16-rc6
References: git-fixes

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.

Fixes: 8bec4337ad40 ("firmware: scpi: add device power domain support using genpd")
Reported-by: Pedro Batista <pedbap.g@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: stable@vger.kernel.org
Cc: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20211209120456.696879-1-sudeep.holla@arm.com'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/firmware/scpi_pm_domain.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/firmware/scpi_pm_domain.c b/drivers/firmware/scpi_pm_domain.c
index 51201600d789..800673910b51 100644
--- a/drivers/firmware/scpi_pm_domain.c
+++ b/drivers/firmware/scpi_pm_domain.c
@@ -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;
 
-- 
2.31.1