[PATCH 1/2] mfd: tps65910: Fix possible invalid pointer dereference on regmap_add_irq_chip fail
From: Krzysztof Kozlowski
Date: Wed Mar 12 2014 - 11:51:05 EST
tps65910_irq_init() sets the 'tps65910->chip_irq' before calling
regmap_add_irq_chip(). If this regmap_add_irq_chip() call fails in
memory allocation of regmap_irq_chip_data members then:
1. The 'tps65910->chip_irq' will still hold some value;
2. 'tps65910->irq_data' will be pointing to already freed memory
(because regmap_add_irq_chip() will free it on error);
This results in invalid memory access during driver remove because the
tps65910_irq_exit() tests whether 'tps65910->chip_irq' is not null.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Fixes: 4aab3fadad32 ("mfd: tps65910: Move interrupt implementation code to mfd file")
---
drivers/mfd/tps65910.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/mfd/tps65910.c b/drivers/mfd/tps65910.c
index 1f142d76cbbc..d6573318977f 100644
--- a/drivers/mfd/tps65910.c
+++ b/drivers/mfd/tps65910.c
@@ -251,16 +251,18 @@ static int tps65910_irq_init(struct tps65910 *tps65910, int irq,
break;
}
tps65910->chip_irq = irq;
ret = regmap_add_irq_chip(tps65910->regmap, tps65910->chip_irq,
IRQF_ONESHOT, pdata->irq_base,
tps6591x_irqs_chip, &tps65910->irq_data);
- if (ret < 0)
+ if (ret < 0) {
dev_warn(tps65910->dev, "Failed to add irq_chip %d\n", ret);
+ tps65910->chip_irq = 0;
+ }
return ret;
}
static int tps65910_irq_exit(struct tps65910 *tps65910)
{
if (tps65910->chip_irq > 0)
regmap_del_irq_chip(tps65910->chip_irq, tps65910->irq_data);
--
1.7.9.5
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