[GIT PULL REQUEST] watchdog - v3.10-rc1 patches
From: Wim Van Sebroeck
Date: Thu May 09 2013 - 02:37:02 EST
Hi Linus,
Please pull from 'master' branch of
git://www.linux-watchdog.org/linux-watchdog.git
It will fix a kdump issue in hpwdt and a possible NULL dereference.
This will update the following files:
ath79_wdt.c | 8 +++-----
davinci_wdt.c | 9 ++++-----
s3c2410_wdt.c | 7 +++----
shwdt.c | 7 ++++---
watchdog_dev.c | 3 ++-
5 files changed, 16 insertions(+), 18 deletions(-)
with these Changes:
commit 60403f7a4d9368d187f79cba5e4672d01df37574
Author: Guenter Roeck <linux@xxxxxxxxxxxx>
Date: Fri Apr 5 21:22:43 2013 -0700
watchdog: Fix race condition in registration code
A race condition exists when registering the first watchdog device.
Sequence of events:
- watchdog_register_device calls watchdog_dev_register
- watchdog_dev_register creates the watchdog misc device by calling
misc_register.
At that time, the matching character device (/dev/watchdog0) does not yet
exist, and old_wdd is not set either.
- Userspace gets an event and opens /dev/watchdog
- watchdog_open is called and sets wdd = old_wdd, which is still NULL,
and tries to dereference it. This causes the kernel to panic.
Seen with systemd trying to open /dev/watchdog immediately after
it was created.
Reported-by: Arkadiusz Miskiewicz <arekm@xxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Tested-by: Arkadiusz Miskiewicz <arekm@xxxxxxxx>
Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxx>
commit 6330c7070be6783b82025d2bc259db8413c00182
Author: Sachin Kamat <sachin.kamat@xxxxxxxxxx>
Date: Mon Mar 4 10:36:41 2013 +0530
watchdog: Convert to devm_ioremap_resource()
Use the newly introduced devm_ioremap_resource() instead of
devm_request_and_ioremap() which provides more consistent error handling.
devm_ioremap_resource() provides its own error messages; so all explicit
error messages can be removed from the failure code paths.
Signed-off-by: Sachin Kamat <sachin.kamat@xxxxxxxxxx>
Reviewed-by: Thierry Reding <thierry.reding@xxxxxxxxxxxxxxxxx>
Cc: Gabor Juhos <juhosg@xxxxxxxxxxx>
Cc: Paul Mundt <lethal@xxxxxxxxxxxx>
Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxx>
For completeness, I added the overal diff below.
Greetings,
Wim.
================================================================================
diff --git a/drivers/watchdog/ath79_wdt.c b/drivers/watchdog/ath79_wdt.c
index 8987990..d184c48 100644
--- a/drivers/watchdog/ath79_wdt.c
+++ b/drivers/watchdog/ath79_wdt.c
@@ -253,11 +253,9 @@ static int ath79_wdt_probe(struct platform_device *pdev)
return -EINVAL;
}
- wdt_base = devm_request_and_ioremap(&pdev->dev, res);
- if (!wdt_base) {
- dev_err(&pdev->dev, "unable to remap memory region\n");
- return -ENOMEM;
- }
+ wdt_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(wdt_base))
+ return PTR_ERR(wdt_base);
wdt_clk = devm_clk_get(&pdev->dev, "wdt");
if (IS_ERR(wdt_clk))
diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c
index 7df1fdc..100d4fb 100644
--- a/drivers/watchdog/davinci_wdt.c
+++ b/drivers/watchdog/davinci_wdt.c
@@ -27,6 +27,7 @@
#include <linux/device.h>
#include <linux/clk.h>
#include <linux/slab.h>
+#include <linux/err.h>
#define MODULE_NAME "DAVINCI-WDT: "
@@ -221,11 +222,9 @@ static int davinci_wdt_probe(struct platform_device *pdev)
return -ENOENT;
}
- wdt_base = devm_request_and_ioremap(dev, wdt_mem);
- if (!wdt_base) {
- dev_err(dev, "ioremap failed\n");
- return -EADDRNOTAVAIL;
- }
+ wdt_base = devm_ioremap_resource(dev, wdt_mem);
+ if (IS_ERR(wdt_base))
+ return PTR_ERR(wdt_base);
ret = misc_register(&davinci_wdt_miscdev);
if (ret < 0) {
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index c1a221c..ee03135 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -330,10 +330,9 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
}
/* get the memory region for the watchdog timer */
- wdt_base = devm_request_and_ioremap(dev, wdt_mem);
- if (wdt_base == NULL) {
- dev_err(dev, "failed to devm_request_and_ioremap() region\n");
- ret = -ENOMEM;
+ wdt_base = devm_ioremap_resource(dev, wdt_mem);
+ if (IS_ERR(wdt_base)) {
+ ret = PTR_ERR(wdt_base);
goto err;
}
diff --git a/drivers/watchdog/shwdt.c b/drivers/watchdog/shwdt.c
index 6a89e40..6185af2 100644
--- a/drivers/watchdog/shwdt.c
+++ b/drivers/watchdog/shwdt.c
@@ -34,6 +34,7 @@
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/clk.h>
+#include <linux/err.h>
#include <asm/watchdog.h>
#define DRV_NAME "sh-wdt"
@@ -249,9 +250,9 @@ static int sh_wdt_probe(struct platform_device *pdev)
wdt->clk = NULL;
}
- wdt->base = devm_request_and_ioremap(wdt->dev, res);
- if (unlikely(!wdt->base)) {
- rc = -EADDRNOTAVAIL;
+ wdt->base = devm_ioremap_resource(wdt->dev, res);
+ if (IS_ERR(wdt->base)) {
+ rc = PTR_ERR(wdt->base);
goto err;
}
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 08b48bb..faf4e18 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -523,6 +523,7 @@ int watchdog_dev_register(struct watchdog_device *watchdog)
int err, devno;
if (watchdog->id == 0) {
+ old_wdd = watchdog;
watchdog_miscdev.parent = watchdog->parent;
err = misc_register(&watchdog_miscdev);
if (err != 0) {
@@ -531,9 +532,9 @@ int watchdog_dev_register(struct watchdog_device *watchdog)
if (err == -EBUSY)
pr_err("%s: a legacy watchdog module is probably present.\n",
watchdog->info->identity);
+ old_wdd = NULL;
return err;
}
- old_wdd = watchdog;
}
/* Fill in the data structures */
--
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