linux-kernel - [PATCH 3/3] dmaengine: stm32-mdma: fix reference leak in stm32-mdma

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] [day] [month] [year] [list]

Date:   Fri, 27 Nov 2020 17:45:25 +0800
From:   Qinglang Miao <miaoqinglang@...wei.com>
To:     Vinod Koul <vkoul@...nel.org>,
        Dan Williams <dan.j.williams@...el.com>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        Alexandre Torgue <alexandre.torgue@...com>
CC:     <dmaengine@...r.kernel.org>,
        <linux-stm32@...md-mailman.stormreply.com>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>,
        Qinglang Miao <miaoqinglang@...wei.com>
Subject: [PATCH 3/3] dmaengine: stm32-mdma: fix reference leak in stm32-mdma

pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to putting operation will result in a
reference leak here.

A new function pm_runtime_resume_and_get is introduced in
[0] to keep usage counter balanced. So We fix the reference
leak by replacing it with new funtion.

[0] dd8088d5a896 ("PM: runtime: Add  pm_runtime_resume_and_get to deal with usage counter")

Fixes: 7cb819c856d9 ("dmaengine: stm32-mdma: add suspend/resume power management support")
Reported-by: Hulk Robot <hulkci@...wei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@...wei.com>
---
 drivers/dma/stm32-mdma.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
index 08cfbfab8..9d4739237 100644
--- a/drivers/dma/stm32-mdma.c
+++ b/drivers/dma/stm32-mdma.c
@@ -1448,7 +1448,7 @@ static int stm32_mdma_alloc_chan_resources(struct dma_chan *c)
 		return -ENOMEM;
 	}
 
-	ret = pm_runtime_get_sync(dmadev->ddev.dev);
+	ret = pm_runtime_resume_and_get(dmadev->ddev.dev);
 	if (ret < 0)
 		return ret;
 
@@ -1714,7 +1714,7 @@ static int stm32_mdma_pm_suspend(struct device *dev)
 	u32 ccr, id;
 	int ret;
 
-	ret = pm_runtime_get_sync(dev);
+	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0)
 		return ret;
 
-- 
2.23.0