linux-kernel - [PATCH v2] USB: serial: io_edgeport: mark expected switch fall-throughs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190501213329.GA26972@embeddedor>
Date:   Wed, 1 May 2019 16:33:29 -0500
From:   "Gustavo A. R. Silva" <gustavo@...eddedor.com>
To:     Johan Hovold <johan@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:     linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org,
        "Gustavo A. R. Silva" <gustavo@...eddedor.com>,
        Kees Cook <keescook@...omium.org>
Subject: [PATCH v2] USB: serial: io_edgeport: mark expected switch
 fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warnings:

drivers/usb/serial/io_edgeport.c: In function ‘process_rcvd_data’:
drivers/usb/serial/io_edgeport.c:1750:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
    if (bufferLength == 0) {
       ^
drivers/usb/serial/io_edgeport.c:1755:3: note: here
   case EXPECT_HDR2:
   ^~~~
drivers/usb/serial/io_edgeport.c:1810:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
     if (bufferLength == 0) {
        ^
drivers/usb/serial/io_edgeport.c:1816:3: note: here
   case EXPECT_DATA: /* Expect data */
   ^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

Notice that, in this particular case, the code comments are modified
in accordance with what GCC is expecting to find.

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@...eddedor.com>
---
Changes in v2:
 - Warning level 3 is now used: -Wimplicit-fallthrough=3
   instead of warning level 2.
 - All warnings in the switch statement are addressed now.

Notice that these are the last remaining fall-through warnings
in the USB subsystem. :)

Thanks
--
Gustavo

 drivers/usb/serial/io_edgeport.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c
index 4ca31c0e4174..7ad10328f4e2 100644
--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -1751,7 +1751,7 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial,
 				edge_serial->rxState = EXPECT_HDR2;
 				break;
 			}
-			/* otherwise, drop on through */
+			/* Fall through - otherwise, drop on through */
 		case EXPECT_HDR2:
 			edge_serial->rxHeader2 = *buffer;
 			++buffer;
@@ -1813,6 +1813,7 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial,
 				}
 				/* Else, drop through */
 			}
+			/* Fall through */
 		case EXPECT_DATA: /* Expect data */
 			if (bufferLength < edge_serial->rxBytesRemaining) {
 				rxLen = bufferLength;
-- 
2.21.0