Merge tag 'mac80211-for-davem-2018-05-09' of git://git.kernel.org/pub/scm/linux/kerne...

[sfrench/cifs-2.6.git] / drivers / amba / bus.c

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 594c228d2f02112345ebc2ad345cd02a7e563a52..4a3ac31c07d0ee49615a00af001e49ff8e30f005 100644 (file)
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -69,11 +69,12 @@ static ssize_t driver_override_show(struct device *_dev,
                                    struct device_attribute *attr, char *buf)
 {
        struct amba_device *dev = to_amba_device(_dev);
+       ssize_t len;
 
-       if (!dev->driver_override)
-               return 0;
-
-       return sprintf(buf, "%s\n", dev->driver_override);
+       device_lock(_dev);
+       len = sprintf(buf, "%s\n", dev->driver_override);
+       device_unlock(_dev);
+       return len;
 }
 
 static ssize_t driver_override_store(struct device *_dev,
@@ -81,9 +82,10 @@ static ssize_t driver_override_store(struct device *_dev,
                                     const char *buf, size_t count)
 {
        struct amba_device *dev = to_amba_device(_dev);
-       char *driver_override, *old = dev->driver_override, *cp;
+       char *driver_override, *old, *cp;
 
-       if (count > PATH_MAX)
+       /* We need to keep extra room for a newline */
+       if (count >= (PAGE_SIZE - 1))
                return -EINVAL;
 
        driver_override = kstrndup(buf, count, GFP_KERNEL);
@@ -94,12 +96,15 @@ static ssize_t driver_override_store(struct device *_dev,
        if (cp)
                *cp = '\0';
 
+       device_lock(_dev);
+       old = dev->driver_override;
        if (strlen(driver_override)) {
                dev->driver_override = driver_override;
        } else {
               kfree(driver_override);
               dev->driver_override = NULL;
        }
+       device_unlock(_dev);
 
        kfree(old);