[PATCH] thermal/int340x_thermal: handle data_vault when the value is ZERO_SIZE_PTR

Lee, Chun-Yi
2022-08-08T13:22:32Z

In some case, the GDDV returns a package with a buffer which has
zero length. It causes that kmemdup() returns ZERO_SIZE_PTR (0x10).

Then the data_vault_read() got NULL point dereference problem when
accessing the 0x10 value in data_vault.

[ 71.024560] BUG: kernel NULL pointer dereference, address:
0000000000000010

This patch uses ZERO_OR_NULL_PTR() for checking ZERO_SIZE_PTR or
NULL value in data_vault.

Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
---
drivers/thermal/intel/int340x_thermal/int3400_thermal.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/thermal/intel/int340x_thermal/int3400_thermal.c b/drivers/thermal/intel/int340x_thermal/int3400_thermal.c
index 80d4e0676083..365489bf4b8c 100644
--- a/drivers/thermal/intel/int340x_thermal/int3400_thermal.c
+++ b/drivers/thermal/intel/int340x_thermal/int3400_thermal.c
@@ -527,7 +527,7 @@ static void int3400_setup_gddv(struct int3400_thermal_priv *priv)
priv->data_vault = kmemdup(obj->package.elements[0].buffer.pointer,
obj->package.elements[0].buffer.length,
GFP_KERNEL);
- if (!priv->data_vault)
+ if (ZERO_OR_NULL_PTR(priv->data_vault))
goto out_free;

bin_attr_data_vault.private = priv->data_vault;
@@ -597,7 +597,7 @@ static int int3400_thermal_probe(struct platform_device *pdev)
goto free_imok;
}

- if (priv->data_vault) {
+ if (!ZERO_OR_NULL_PTR(priv->data_vault)) {
result = sysfs_create_group(&pdev->dev.kobj,
&data_attribute_group);
if (result)
@@ -615,7 +615,8 @@ static int int3400_thermal_probe(struct platform_device *pdev)
free_sysfs:
cleanup_odvp(priv);
if (priv->data_vault) {
- sysfs_remove_group(&pdev->dev.kobj, &data_attribute_group);
+ if (!ZERO_OR_NULL_PTR(priv->data_vault))
+ sysfs_remove_group(&pdev->dev.kobj, &data_attribute_group);
kfree(priv->data_vault);
}
free_uuid:
@@ -647,7 +648,7 @@ static int int3400_thermal_remove(struct platform_device *pdev)
if (!priv->rel_misc_dev_res)
acpi_thermal_rel_misc_device_remove(priv->adev->handle);

- if (priv->data_vault)
+ if (!ZERO_OR_NULL_PTR(priv->data_vault))
sysfs_remove_group(&pdev->dev.kobj, &data_attribute_group);
sysfs_remove_group(&pdev->dev.kobj, &uuid_attribute_group);
sysfs_remove_group(&pdev->dev.kobj, &imok_attribute_group);
--
2.26.2