linux-kernel - [PATCH 3.12 008/175] HID: i2c-hid: Limit reads to wMaxInputLength bytes for input events

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

Date:	Tue, 17 Mar 2015 09:39:46 +0100
From:	Jiri Slaby <jslaby@...e.cz>
To:	stable@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org,
	Seth Forshee <seth.forshee@...onical.com>,
	Jiri Kosina <jkosina@...e.cz>, Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 3.12 008/175] HID: i2c-hid: Limit reads to wMaxInputLength bytes for input events

From: Seth Forshee <seth.forshee@...onical.com>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit 6d00f37e49d95e640a3937a4a1ae07dbe92a10cb upstream.

d1c7e29e8d27 (HID: i2c-hid: prevent buffer overflow in early IRQ)
changed hid_get_input() to read ihid->bufsize bytes, which can be
more than wMaxInputLength. This is the case with the Dell XPS 13
9343, and it is causing events to be missed. In some cases the
missed events are releases, which can cause the cursor to jump or
freeze, among other problems. Limit the number of bytes read to
min(wMaxInputLength, ihid->bufsize) to prevent such problems.

Fixes: d1c7e29e8d27 "HID: i2c-hid: prevent buffer overflow in early IRQ"
Signed-off-by: Seth Forshee <seth.forshee@...onical.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@...hat.com>
Signed-off-by: Jiri Kosina <jkosina@...e.cz>
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
 drivers/hid/i2c-hid/i2c-hid.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index e29d8a0feb5f..f62c65ec117e 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -356,7 +356,10 @@ static int i2c_hid_hwreset(struct i2c_client *client)
 static void i2c_hid_get_input(struct i2c_hid *ihid)
 {
 	int ret, ret_size;
-	int size = ihid->bufsize;
+	int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
+
+	if (size > ihid->bufsize)
+		size = ihid->bufsize;
 
 	ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
 	if (ret != size) {
-- 
2.3.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/