diff options
| author | Adrian Salido <salidoa@google.com> | 2017-08-31 12:22:19 +0200 |
|---|---|---|
| committer | Bertolin, PierreX <pierrex.bertolin@intel.com> | 2017-09-05 06:21:46 -0700 |
| commit | 6bba6e5d2ca57cf1d4f8029786ce76d0769d7aab (patch) | |
| tree | 100b69f2b5ca1cd7c9ce3bc40521ef7c9cfd0fbf | |
| parent | f7e5b8ec60ed56a29cdfb1df71235b2ec90bceec (diff) | |
| download | x86-6bba6e5d2ca57cf1d4f8029786ce76d0769d7aab.tar.gz | |
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.
Change-Id: I061524fce8db41d3723199b727fc93b932a12a04
Fixes: 3d713e0e382e ("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>
Tracked-On: https://jira01.devtools.intel.com/browse/AW-6921
Signed-off-by: Loic Akue <loicx.akue@intel.com>
Reviewed-on: https://android.intel.com/598752
Reviewed-by: Dubray, SimonX <simonx.dubray@intel.com>
Reviewed-by: Tasayco Loarte, VictorX <victorx.tasayco.loarte@intel.com>
Reviewed-by: Ledentec, AlexandreX <alexandrex.ledentec@intel.com>
| -rw-r--r-- | drivers/base/platform.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 176b59f5bc47..285aa2268c67 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -807,7 +807,7 @@ 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; @@ -820,12 +820,15 @@ 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); @@ -836,8 +839,12 @@ 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); |