mirror of
https://github.com/torvalds/linux.git
synced 2024-11-23 04:31:50 +00:00
driver core: platform: fix race condition with driver_override
The driver_override implementation is susceptible to race condition when
different threads are reading vs storing a different driver override.
Add locking to avoid race condition.
Fixes: 3d713e0e38
("driver core: platform: add device binding path 'driver_override'")
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Salido <salidoa@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
08332893e3
commit
6265539776
@ -866,7 +866,7 @@ static ssize_t driver_override_store(struct device *dev,
|
||||
const char *buf, size_t count)
|
||||
{
|
||||
struct platform_device *pdev = to_platform_device(dev);
|
||||
char *driver_override, *old = pdev->driver_override, *cp;
|
||||
char *driver_override, *old, *cp;
|
||||
|
||||
if (count > PATH_MAX)
|
||||
return -EINVAL;
|
||||
@ -879,12 +879,15 @@ static ssize_t driver_override_store(struct device *dev,
|
||||
if (cp)
|
||||
*cp = '\0';
|
||||
|
||||
device_lock(dev);
|
||||
old = pdev->driver_override;
|
||||
if (strlen(driver_override)) {
|
||||
pdev->driver_override = driver_override;
|
||||
} else {
|
||||
kfree(driver_override);
|
||||
pdev->driver_override = NULL;
|
||||
}
|
||||
device_unlock(dev);
|
||||
|
||||
kfree(old);
|
||||
|
||||
@ -895,8 +898,12 @@ static ssize_t driver_override_show(struct device *dev,
|
||||
struct device_attribute *attr, char *buf)
|
||||
{
|
||||
struct platform_device *pdev = to_platform_device(dev);
|
||||
ssize_t len;
|
||||
|
||||
return sprintf(buf, "%s\n", pdev->driver_override);
|
||||
device_lock(dev);
|
||||
len = sprintf(buf, "%s\n", pdev->driver_override);
|
||||
device_unlock(dev);
|
||||
return len;
|
||||
}
|
||||
static DEVICE_ATTR_RW(driver_override);
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user