[PATCH 5.19 307/717] platform/chrome: fix double-free in chromeos_laptop_prepare()

Greg Kroah-Hartman
2022-10-22T08:06:19Z

From: Rustam Subkhankulov <subkhankulov@ispras.ru>

[ Upstream commit 6ad4194d6a1e1d11b285989cd648ef695b4a93c0 ]

If chromeos_laptop_prepare_i2c_peripherals() fails after allocating memory
for 'cros_laptop->i2c_peripherals', this memory is freed at 'err_out' label
and nonzero value is returned. Then chromeos_laptop_destroy() is called,
resulting in double-free error.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Rustam Subkhankulov <subkhankulov@ispras.ru>
Fixes: 5020cd29d8bf ("platform/chrome: chromeos_laptop - supply properties for ACPI devices")
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220813220843.2373004-1-subkhankulov@ispras.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/platform/chrome/chromeos_laptop.c | 24 ++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/platform/chrome/chromeos_laptop.c b/drivers/platform/chrome/chromeos_laptop.c
index 4e14b4d6635d..a2cdbfbaeae6 100644
--- a/drivers/platform/chrome/chromeos_laptop.c
+++ b/drivers/platform/chrome/chromeos_laptop.c
@@ -740,6 +740,7 @@ static int __init
chromeos_laptop_prepare_i2c_peripherals(struct chromeos_laptop *cros_laptop,
const struct chromeos_laptop *src)
{
+ struct i2c_peripheral *i2c_peripherals;
struct i2c_peripheral *i2c_dev;
struct i2c_board_info *info;
int i;
@@ -748,17 +749,15 @@ chromeos_laptop_prepare_i2c_peripherals(struct chromeos_laptop *cros_laptop,
if (!src->num_i2c_peripherals)
return 0;

- cros_laptop->i2c_peripherals = kmemdup(src->i2c_peripherals,
- src->num_i2c_peripherals *
- sizeof(*src->i2c_peripherals),
- GFP_KERNEL);
- if (!cros_laptop->i2c_peripherals)
+ i2c_peripherals = kmemdup(src->i2c_peripherals,
+ src->num_i2c_peripherals *
+ sizeof(*src->i2c_peripherals),
+ GFP_KERNEL);
+ if (!i2c_peripherals)
return -ENOMEM;

- cros_laptop->num_i2c_peripherals = src->num_i2c_peripherals;
-
- for (i = 0; i < cros_laptop->num_i2c_peripherals; i++) {
- i2c_dev = &cros_laptop->i2c_peripherals[i];
+ for (i = 0; i < src->num_i2c_peripherals; i++) {
+ i2c_dev = &i2c_peripherals[i];
info = &i2c_dev->board_info;

error = chromeos_laptop_setup_irq(i2c_dev);
@@ -775,16 +774,19 @@ chromeos_laptop_prepare_i2c_peripherals(struct chromeos_laptop *cros_laptop,
}
}

+ cros_laptop->i2c_peripherals = i2c_peripherals;
+ cros_laptop->num_i2c_peripherals = src->num_i2c_peripherals;
+
return 0;

err_out:
while (--i >= 0) {
- i2c_dev = &cros_laptop->i2c_peripherals[i];
+ i2c_dev = &i2c_peripherals[i];
info = &i2c_dev->board_info;
if (!IS_ERR_OR_NULL(info->fwnode))
fwnode_remove_software_node(info->fwnode);
}
- kfree(cros_laptop->i2c_peripherals);
+ kfree(i2c_peripherals);
return error;
}

--
2.35.1