linux-kernel - [PATCH v3] [ARM] fix reference leak in locomo_init_one

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-next>] [day] [month] [year] [list]

Message-Id: <20250107020714.662708-1-make24@iscas.ac.cn>
Date: Tue,  7 Jan 2025 10:07:14 +0800
From: Ma Ke <make24@...as.ac.cn>
To: linux@...linux.org.uk,
	elder@...nel.org,
	sumit.garg@...aro.org,
	gregkh@...uxfoundation.org,
	make24@...as.ac.cn
Cc: linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	stable@...r.kernel.org
Subject: [PATCH v3] [ARM] fix reference leak in locomo_init_one_child()

Once device_register() failed, we should call put_device() to
decrement reference count for cleanup. Or it could cause memory leak.

device_register() includes device_add(). As comment of device_add()
says, 'if device_add() succeeds, you should call device_del() when you
want to get rid of it. If device_add() has not succeeded, use only
put_device() to drop the reference count'.

Found by code review.

Cc: stable@...r.kernel.org
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Ma Ke <make24@...as.ac.cn>
---
Changes in v3:
- modified the patch as suggestions;
Changes in v2:
- modified the patch as suggestions.
---
 arch/arm/common/locomo.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/arch/arm/common/locomo.c b/arch/arm/common/locomo.c
index cb6ef449b987..9e275b2105c2 100644
--- a/arch/arm/common/locomo.c
+++ b/arch/arm/common/locomo.c
@@ -220,13 +220,11 @@ static int
 locomo_init_one_child(struct locomo *lchip, struct locomo_dev_info *info)
 {
 	struct locomo_dev *dev;
-	int ret;
+	int ret = 0;
 
 	dev = kzalloc(sizeof(struct locomo_dev), GFP_KERNEL);
-	if (!dev) {
-		ret = -ENOMEM;
-		goto out;
-	}
+	if (!dev)
+		return -ENOMEM;
 
 	/*
 	 * If the parent device has a DMA mask associated with it,
@@ -254,10 +252,9 @@ locomo_init_one_child(struct locomo *lchip, struct locomo_dev_info *info)
 			NO_IRQ : lchip->irq_base + info->irq[0];
 
 	ret = device_register(&dev->dev);
-	if (ret) {
- out:
-		kfree(dev);
-	}
+	if (ret)
+		put_device(&dev->dev);
+
 	return ret;
 }
 
-- 
2.25.1