[PATCH 1/2] ACPI: x86: s2idle: Fix a NULL pointer dereference

From: Mario Limonciello
Date: Wed Sep 28 2022 - 12:20:04 EST


Ryzen 7000 (Raphael) introduced AMDI0008 for _HID. This ID was added
in commit ed470febf837 ("ACPI: PM: s2idle: Add support for upcoming AMD
uPEP HID AMDI008"), but then removed in favor of aligning all new IDs
to Rembrandt support in commit fd894f05cf30 ("ACPI: x86: s2idle: If a
new AMD _HID is missing assume Rembrandt").

Unfortunately there was a mistake in commit 100a57379380 ("ACPI: x86:
s2idle: Move _HID handling for AMD systems into structures") that can
lead to a NULL pointer dereference accessing `dev_id->driver_data` in
the sentinel of `amd_hid_ids`. Fix this dereference.

Reported-by: Richard Gong <Richard.Gong@xxxxxxx>
Fixes: 100a57379380 ("ACPI: x86: s2idle: Move _HID handling for AMD systems into structures")
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
drivers/acpi/x86/s2idle.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index eedd21d8a284..3ae2ba74de92 100644
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -470,7 +470,7 @@ static int lps0_device_attach(struct acpi_device *adev,
for (dev_id = &amd_hid_ids[0]; dev_id->id[0]; dev_id++)
if (acpi_dev_hid_uid_match(adev, dev_id->id, NULL))
break;
- if (dev_id)
+ if (dev_id->id[0])
data = (const struct amd_lps0_hid_device_data *) dev_id->driver_data;
else
data = &amd_rembrandt;
--
2.34.1