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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Cc: Zheyu Ma <zheyuma97@gmail.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Sasha Levin <sashal@kernel.org>,
	mcgrof@kernel.org,
	andriy.shevchenko@linux.intel.com,
	tzimmermann@suse.de,
	hkallweit1@gmail.com,
	gregkh@linuxfoundation.org,
	linux-media@vger.kernel.org
Subject: [PATCH AUTOSEL 6.6 10/16] media: lgdt3306a: Add a check against null-pointer-def
Date: Mon, 27 May 2024 11:55:01 -0400
Message-ID: <20240527155541.3865428-10-sashal@kernel.org>
In-Reply-To: <20240527155541.3865428-1-sashal@kernel.org>
References: <20240527155541.3865428-1-sashal@kernel.org>
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From: Zheyu Ma <zheyuma97@gmail.com>

[ Upstream commit c1115ddbda9c930fba0fdd062e7a8873ebaf898d ]

The driver should check whether the client provides the platform_data.

The following log reveals it:

[   29.610324] BUG: KASAN: null-ptr-deref in kmemdup+0x30/0x40
[   29.610730] Read of size 40 at addr 0000000000000000 by task bash/414
[   29.612820] Call Trace:
[   29.613030]  <TASK>
[   29.613201]  dump_stack_lvl+0x56/0x6f
[   29.613496]  ? kmemdup+0x30/0x40
[   29.613754]  print_report.cold+0x494/0x6b7
[   29.614082]  ? kmemdup+0x30/0x40
[   29.614340]  kasan_report+0x8a/0x190
[   29.614628]  ? kmemdup+0x30/0x40
[   29.614888]  kasan_check_range+0x14d/0x1d0
[   29.615213]  memcpy+0x20/0x60
[   29.615454]  kmemdup+0x30/0x40
[   29.615700]  lgdt3306a_probe+0x52/0x310
[   29.616339]  i2c_device_probe+0x951/0xa90

Link: https://lore.kernel.org/linux-media/20220405095018.3993578-1-zheyuma97@gmail.com
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/media/dvb-frontends/lgdt3306a.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/media/dvb-frontends/lgdt3306a.c b/drivers/media/dvb-frontends/lgdt3306a.c
index 2638875924153..231b45632ad5a 100644
--- a/drivers/media/dvb-frontends/lgdt3306a.c
+++ b/drivers/media/dvb-frontends/lgdt3306a.c
@@ -2176,6 +2176,11 @@ static int lgdt3306a_probe(struct i2c_client *client)
 	struct dvb_frontend *fe;
 	int ret;
 
+	if (!client->dev.platform_data) {
+		dev_err(&client->dev, "platform data is mandatory\n");
+		return -EINVAL;
+	}
+
 	config = kmemdup(client->dev.platform_data,
 			 sizeof(struct lgdt3306a_config), GFP_KERNEL);
 	if (config == NULL) {
-- 
2.43.0