linux-kernel - [PATCH AUTOSEL 4.4 04/18] gpio: adp5588: Fix sleep-in-atomic-context bug

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180924144942.164688-4-alexander.levin@microsoft.com>
Date:   Mon, 24 Sep 2018 14:49:47 +0000
From:   Sasha Levin <Alexander.Levin@...rosoft.com>
To:     "stable@...r.kernel.org" <stable@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:     Michael Hennerich <michael.hennerich@...log.com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Sasha Levin <Alexander.Levin@...rosoft.com>
Subject: [PATCH AUTOSEL 4.4 04/18] gpio: adp5588: Fix sleep-in-atomic-context
 bug

From: Michael Hennerich <michael.hennerich@...log.com>

[ Upstream commit 6537886cdc9a637711fd6da980dbb87c2c87c9aa ]

This fixes:
[BUG] gpio: gpio-adp5588: A possible sleep-in-atomic-context bug
                          in adp5588_gpio_write()
[BUG] gpio: gpio-adp5588: A possible sleep-in-atomic-context bug
                          in adp5588_gpio_direction_input()

Reported-by: Jia-Ju Bai <baijiaju1990@...il.com>
Signed-off-by: Michael Hennerich <michael.hennerich@...log.com>
Signed-off-by: Linus Walleij <linus.walleij@...aro.org>
Signed-off-by: Sasha Levin <alexander.levin@...rosoft.com>
---
 drivers/gpio/gpio-adp5588.c | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpio-adp5588.c b/drivers/gpio/gpio-adp5588.c
index 984186ee58a0..f5f7b5368da6 100644
--- a/drivers/gpio/gpio-adp5588.c
+++ b/drivers/gpio/gpio-adp5588.c
@@ -41,6 +41,8 @@ struct adp5588_gpio {
 	uint8_t int_en[3];
 	uint8_t irq_mask[3];
 	uint8_t irq_stat[3];
+	uint8_t int_input_en[3];
+	uint8_t int_lvl_cached[3];
 };
 
 static int adp5588_gpio_read(struct i2c_client *client, u8 reg)
@@ -177,12 +179,28 @@ static void adp5588_irq_bus_sync_unlock(struct irq_data *d)
 	struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
 	int i;
 
-	for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++)
+	for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
+		if (dev->int_input_en[i]) {
+			mutex_lock(&dev->lock);
+			dev->dir[i] &= ~dev->int_input_en[i];
+			dev->int_input_en[i] = 0;
+			adp5588_gpio_write(dev->client, GPIO_DIR1 + i,
+					   dev->dir[i]);
+			mutex_unlock(&dev->lock);
+		}
+
+		if (dev->int_lvl_cached[i] != dev->int_lvl[i]) {
+			dev->int_lvl_cached[i] = dev->int_lvl[i];
+			adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + i,
+					   dev->int_lvl[i]);
+		}
+
 		if (dev->int_en[i] ^ dev->irq_mask[i]) {
 			dev->int_en[i] = dev->irq_mask[i];
 			adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i,
 					   dev->int_en[i]);
 		}
+	}
 
 	mutex_unlock(&dev->irq_lock);
 }
@@ -225,9 +243,7 @@ static int adp5588_irq_set_type(struct irq_data *d, unsigned int type)
 	else
 		return -EINVAL;
 
-	adp5588_gpio_direction_input(&dev->gpio_chip, gpio);
-	adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + bank,
-			   dev->int_lvl[bank]);
+	dev->int_input_en[bank] |= bit;
 
 	return 0;
 }
-- 
2.17.1