From 4bf4eed44bfe288f459496eaf38089502ef91a79 Mon Sep 17 00:00:00 2001
From: Anton Vasilyev <vasilyev@ispras.ru>
Date: Mon, 23 Jul 2018 19:53:30 +0300
Subject: [PATCH] gpio: ml-ioh: Fix buffer underwrite on probe error path
Git-commit: 4bf4eed44bfe288f459496eaf38089502ef91a79
Patch-mainline: v4.19-rc1
References: bsc#1051510
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 <vasilyev@ispras.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
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