linux-kernel - [PATCH] engine: stm32-dma: call pm_runtime_put if pm_runtime_get

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]

Date:   Wed,  3 Jun 2020 13:34:10 -0500
From:   Navid Emamdoost <navid.emamdoost@...il.com>
To:     Dan Williams <dan.j.williams@...el.com>,
        Vinod Koul <vkoul@...nel.org>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        Alexandre Torgue <alexandre.torgue@...com>,
        dmaengine@...r.kernel.org,
        linux-stm32@...md-mailman.stormreply.com,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Cc:     emamd001@....edu, wu000273@....edu, kjlu@....edu, smccaman@....edu,
        Navid Emamdoost <navid.emamdoost@...il.com>
Subject: [PATCH] engine: stm32-dma: call pm_runtime_put if pm_runtime_get_sync fails

Calling pm_runtime_get_sync increments the counter even in case of
failure, causing incorrect ref count. Call pm_runtime_put if
pm_runtime_get_sync fails.

Signed-off-by: Navid Emamdoost <navid.emamdoost@...il.com>
---
 drivers/dma/stm32-dma.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index 0ddbaa4b4f0b..0aab86bd97fe 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -1169,8 +1169,10 @@ static int stm32_dma_alloc_chan_resources(struct dma_chan *c)
 	chan->config_init = false;
 
 	ret = pm_runtime_get_sync(dmadev->ddev.dev);
-	if (ret < 0)
+	if (ret < 0) {
+		pm_runtime_put(dmadev->ddev.dev);
 		return ret;
+	}
 
 	ret = stm32_dma_disable_chan(chan);
 	if (ret < 0)
@@ -1439,8 +1441,10 @@ static int stm32_dma_suspend(struct device *dev)
 	int id, ret, scr;
 
 	ret = pm_runtime_get_sync(dev);
-	if (ret < 0)
+	if (ret < 0) {
+		pm_runtime_put_sync(dev);
 		return ret;
+	}
 
 	for (id = 0; id < STM32_DMA_MAX_CHANNELS; id++) {
 		scr = stm32_dma_read(dmadev, STM32_DMA_SCR(id));
-- 
2.17.1