From: Johan Hovold <johan@kernel.org>
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
Johan Hovold <johan@kernel.org>
Subject: [PATCH v2] Input: usbtouchscreen - add driver_info sanity check
Date: Thu, 23 Jun 2022 08:24:46 +0200 [thread overview]
Message-ID: <20220623062446.16944-1-johan@kernel.org> (raw)
Add a sanity check on the device id-table driver_info field to make sure
we never access a type structure (and function pointers) outside of the
device info array (e.g. if someone fails to ifdef a device-id entry).
Note that this also suppresses a compiler warning with -Warray-bounds
(gcc-11.3.0) when compile-testing the driver without enabling any of
the device type Kconfig options:
drivers/input/touchscreen/usbtouchscreen.c: In function 'usbtouch_probe':
drivers/input/touchscreen/usbtouchscreen.c:1668:16:warning: array subscript <unknown> is outside array bounds of 'struct usbtouch_device_info[0]' [-Warray-bounds]
1668 | type = &usbtouch_dev_info[id->driver_info];
Signed-off-by: Johan Hovold <johan@kernel.org>
---
Changes in v2
- use ARRAY_SIZE() for the sanity check (Dmitry)
- drop the dummy entry and combine the two patches as the sanity check
itself is enough to suppress the compiler warning (Dmitry)
- use -ENODEV instead of -EINVAL even if this means no error will be
logged in the unlikely event of a future driver bug
drivers/input/touchscreen/usbtouchscreen.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c
index 43c521f50c85..b01d026588c8 100644
--- a/drivers/input/touchscreen/usbtouchscreen.c
+++ b/drivers/input/touchscreen/usbtouchscreen.c
@@ -1654,6 +1654,9 @@ static int usbtouch_probe(struct usb_interface *intf,
if (id->driver_info == DEVTYPE_IGNORE)
return -ENODEV;
+ if (id->driver_info >= ARRAY_SIZE(usbtouch_dev_info))
+ return -ENODEV;
+
endpoint = usbtouch_get_input_endpoint(intf->cur_altsetting);
if (!endpoint)
return -ENXIO;
--
2.35.1
next reply other threads:[~2022-06-23 6:25 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-23 6:24 Johan Hovold [this message]
2022-06-23 15:59 ` [PATCH v2] Input: usbtouchscreen - add driver_info sanity check Dmitry Torokhov
2022-06-27 7:46 ` Johan Hovold
2022-06-27 22:13 ` Dmitry Torokhov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220623062446.16944-1-johan@kernel.org \
--to=johan@kernel.org \
--cc=dmitry.torokhov@gmail.com \
--cc=linux-input@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.