staging: logger: hold mutex while removing reader

The readers list is traversed under the log->mutex lock
(for example from fix_up_readers()), but the deletion of
elements from this list is not being done under this lock.

Cc: Brian Swetland <swetland@google.com>
Cc: Dima Zavin <dima@android.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index 0d2367f2c15f5eb30bfedc64deaaf7ad6eebc228..ea69b6a77dac9da1ac667506fa52efe7d694fe74 100644 (file)
--- a/drivers/staging/android/logger.c
+++ b/drivers/staging/android/logger.c
@@ -459,7 +459,12 @@ static int logger_release(struct inode *ignored, struct file *file)
 {
        if (file->f_mode & FMODE_READ) {
                struct logger_reader *reader = file->private_data;
+               struct logger_log *log = reader->log;
+
+               mutex_lock(&log->mutex);
                list_del(&reader->list);
+               mutex_unlock(&log->mutex);
+
                kfree(reader);
        }