[PATCH v2] usb: storage: initialize variable

From: trix@redhat.com
To: stern@rowland.harvard.edu, gregkh@linuxfoundation.org
Cc: linux-usb@vger.kernel.org, usb-storage@lists.one-eyed-alien.net,
	linux-kernel@vger.kernel.org, Tom Rix <trix@redhat.com>
Subject: [PATCH v2] usb: storage: initialize variable
Date: Mon, 24 Aug 2020 14:10:27 -0700	[thread overview]
Message-ID: <20200824211027.11543-1-trix@redhat.com> (raw)

From: Tom Rix <trix@redhat.com>

clang static analysis reports this representative problem

transport.c:495:15: warning: Assigned value is garbage or
  undefined
        length_left -= partial;
                   ^  ~~~~~~~
partial is set only when usb_stor_bulk_transfer_sglist()
is successful.

So set partial on entry to 0.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Tom Rix <trix@redhat.com>
---
 drivers/usb/storage/transport.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
index 238a8088e17f..044429717dcc 100644
--- a/drivers/usb/storage/transport.c
+++ b/drivers/usb/storage/transport.c
@@ -414,6 +414,9 @@ static int usb_stor_bulk_transfer_sglist(struct us_data *us, unsigned int pipe,
 {
 	int result;
 
+	if (act_len)
+		*act_len = 0;
+
 	/* don't submit s-g requests during abort processing */
 	if (test_bit(US_FLIDX_ABORTING, &us->dflags))
 		return USB_STOR_XFER_ERROR;
-- 
2.18.1

