linux-kernel - [PATCH 3.2 55/94] mfd: 88pm860x: Fix possible NULL pointer dereference on i2c_new

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: <lsq.1398647482.272433196@decadent.org.uk>
Date:	Mon, 28 Apr 2014 02:11:22 +0100
From:	Ben Hutchings <ben@...adent.org.uk>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:	akpm@...ux-foundation.org, "Lee Jones" <lee.jones@...aro.org>,
	"Krzysztof Kozlowski" <k.kozlowski@...sung.com>
Subject: [PATCH 3.2 55/94] mfd: 88pm860x: Fix possible NULL pointer
 dereference on i2c_new_dummy error

3.2.58-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Krzysztof Kozlowski <k.kozlowski@...sung.com>

commit 159ce52a6b777fc82fa0b51c7440e25f9e4c6feb upstream.

During probe the driver allocates dummy I2C device for companion chip
with i2c_new_dummy() but it does not check the return value of this call.

In case of error (i2c_new_device(): memory allocation failure or I2C
address cannot be used) this function returns NULL which is later used
by regmap_init_i2c().

If i2c_new_dummy() fails for companion device, fail also the probe for
main MFD driver.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@...sung.com>
Signed-off-by: Lee Jones <lee.jones@...aro.org>
[bwh: Backported to 3.2:
 - Adjust filename, context
 - Add kfree() before return, as driver is not using managed allocations]
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 drivers/mfd/88pm860x-i2c.c | 5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/mfd/88pm860x-i2c.c
+++ b/drivers/mfd/88pm860x-i2c.c
@@ -290,6 +290,12 @@ static int __devinit pm860x_probe(struct
 		chip->companion_addr = pdata->companion_addr;
 		chip->companion = i2c_new_dummy(chip->client->adapter,
 						chip->companion_addr);
+		if (!chip->companion) {
+			dev_err(&client->dev,
+				"Failed to allocate I2C companion device\n");
+			kfree(chip);
+			return -ENODEV;
+		}
 		i2c_set_clientdata(chip->companion, chip);
 	}
 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/