From 6ad4194d6a1e1d11b285989cd648ef695b4a93c0 Mon Sep 17 00:00:00 2001 From: Rustam Subkhankulov Date: Sun, 14 Aug 2022 01:08:43 +0300 Subject: [PATCH] platform/chrome: fix double-free in chromeos_laptop_prepare() 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 Fixes: 5020cd29d8bf ("platform/chrome: chromeos_laptop - supply properties for ACPI devices") Reviewed-by: Dmitry Torokhov Signed-off-by: Tzung-Bi Shih Link: https://lore.kernel.org/r/20220813220843.2373004-1-subkhankulov@ispras.ru --- 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 4e14b4d..a2cdbfb 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; } -- 2.7.4