From: Yves-Alexis Perez <cor...@debian.org>

wait_for_completion_interruptible_timeout() return value is either
-ERESTARTSYS (in case it was interrupted), 0 (in case the timeout expired)
or the number of jiffies left until timeout. The return value is stored in
a long, but in _request_firmware_load() it's silently casted to an int,
which can overflow and give a negative value, indicating an error.

Fix this by re-using the timeout variable and only set retval when it's
safe.

Signed-off-by: Yves-Alexis Perez <cor...@corsac.net>
Cc: Ming Lei <ming....@canonical.com>
Cc: "Luis R. Rodriguez" <mcg...@kernel.org>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: sta...@vger.kernel.org

---
 drivers/base/firmware_class.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 22d1760..a95e1e5 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -955,13 +955,14 @@ static int _request_firmware_load(struct firmware_priv 
*fw_priv,
                timeout = MAX_JIFFY_OFFSET;
        }
 
-       retval = wait_for_completion_interruptible_timeout(&buf->completion,
+       timeout = wait_for_completion_interruptible_timeout(&buf->completion,
                        timeout);
-       if (retval == -ERESTARTSYS || !retval) {
+       if (timeout == -ERESTARTSYS || !timeout) {
+               retval = timeout;
                mutex_lock(&fw_lock);
                fw_load_abort(fw_priv);
                mutex_unlock(&fw_lock);
-       } else if (retval > 0) {
+       } else if (timeout > 0) {
                retval = 0;
        }
 
-- 
2.10.1

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