From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anton Vasilyev Subject: [PATCH] gpio: ml-ioh: Fix buffer underwrite on probe error path Date: Mon, 23 Jul 2018 19:53:30 +0300 Message-ID: <20180723165330.25213-1-vasilyev@ispras.ru> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Linus Walleij Cc: Anton Vasilyev , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org List-Id: linux-gpio@vger.kernel.org If ioh_gpio_probe() fails on devm_irq_alloc_descs() then chip may point to any element of chip_save array, so reverse iteration from pointer chip may become chip_save[-1] and gpiochip_remove() will operate with wrong memory. The patch fix the error path of ioh_gpio_probe() to correctly bypass chip_save array. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Anton Vasilyev --- drivers/gpio/gpio-ml-ioh.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-ml-ioh.c b/drivers/gpio/gpio-ml-ioh.c index b23d9a36be1f..51c7d1b84c2e 100644 --- a/drivers/gpio/gpio-ml-ioh.c +++ b/drivers/gpio/gpio-ml-ioh.c @@ -496,9 +496,10 @@ static int ioh_gpio_probe(struct pci_dev *pdev, return 0; err_gpiochip_add: + chip = chip_save; while (--i >= 0) { - chip--; gpiochip_remove(&chip->gpio); + chip++; } kfree(chip_save); -- 2.18.0