linux-kernel - [PATCH] base/platform: assert that dev_pm_domain callbacks are called unconditionally

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]

Date:	Tue, 21 Jul 2015 17:08:35 +0200
From:	Uwe Kleine-König <uwe@...ine-koenig.org>
To:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Mark Brown <broonie@...nel.org>
Cc:	linux-kernel@...r.kernel.org, kernel@...gutronix.de
Subject: [PATCH] base/platform: assert that dev_pm_domain callbacks are called unconditionally

When a platform driver doesn't provide a .remove callback the function
platform_drv_remove isn't called and so the call to dev_pm_domain_attach
called at probe time isn't paired by dev_pm_domain_detach at remove
time.

To fix this (and similar issues if different callbacks are missing) hook
up the driver callbacks unconditionally and make them aware that the
platform callbacks might be missing.

Signed-off-by: Uwe Kleine-König <uwe@...ine-koenig.org>
---
Hello,

I didn't see any breakage without this patch, but it looks wrong the way
it is.

Best regards
Uwe

 drivers/base/platform.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 063f0ab15259..62debf4a1348 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -517,7 +517,7 @@ static int platform_drv_probe(struct device *_dev)
 		return ret;
 
 	ret = dev_pm_domain_attach(_dev, true);
-	if (ret != -EPROBE_DEFER) {
+	if (ret != -EPROBE_DEFER && drv->probe) {
 		ret = drv->probe(dev);
 		if (ret)
 			dev_pm_domain_detach(_dev, true);
@@ -542,7 +542,8 @@ static int platform_drv_remove(struct device *_dev)
 	struct platform_device *dev = to_platform_device(_dev);
 	int ret;
 
-	ret = drv->remove(dev);
+	if (drv->remove)
+		ret = drv->remove(dev);
 	dev_pm_domain_detach(_dev, true);
 
 	return ret;
@@ -553,7 +554,8 @@ static void platform_drv_shutdown(struct device *_dev)
 	struct platform_driver *drv = to_platform_driver(_dev->driver);
 	struct platform_device *dev = to_platform_device(_dev);
 
-	drv->shutdown(dev);
+	if (drv->shutdown)
+		drv->shutdown(dev);
 	dev_pm_domain_detach(_dev, true);
 }
 
@@ -567,12 +569,9 @@ int __platform_driver_register(struct platform_driver *drv,
 {
 	drv->driver.owner = owner;
 	drv->driver.bus = &platform_bus_type;
-	if (drv->probe)
-		drv->driver.probe = platform_drv_probe;
-	if (drv->remove)
-		drv->driver.remove = platform_drv_remove;
-	if (drv->shutdown)
-		drv->driver.shutdown = platform_drv_shutdown;
+	drv->driver.probe = platform_drv_probe;
+	drv->driver.remove = platform_drv_remove;
+	drv->driver.shutdown = platform_drv_shutdown;
 
 	return driver_register(&drv->driver);
 }
-- 
2.1.4

--
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/