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From:   Colin King <colin.king@canonical.com>
To:     Jiri Kosina <jikos@kernel.org>,
        Benjamin Tissoires <benjamin.tissoires@redhat.com>,
        Nestor Lopez Casado <nlopezcasad@logitech.com>,
        linux-input@vger.kernel.org
Cc:     kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] HID: logitech-dj: fix unintentional integer overflow on left shift
Date:   Sun,  7 Feb 2021 23:21:20 +0000
Message-Id: <20210207232120.8885-1-colin.king@canonical.com>
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From: Colin Ian King <colin.king@canonical.com>

Shifting the integer value 1 is evaluated using 32-bit rithmetic
and then used in an expression that expects a 64-bit value, so
there is potentially an integer overflow. Fix this by using th
BIT_ULL macro to perform the shift and avoid the overflow.

Addresses-Coverity: ("Uninitentional integer overflow")
Fixes: 534a7b8e10ec ("HID: Add full support for Logitech Unifying receivers")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/hid/hid-logitech-dj.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/hid-logitech-dj.c b/drivers/hid/hid-logitech-dj.c
index 45e7e0bdd382..747f41be0603 100644
--- a/drivers/hid/hid-logitech-dj.c
+++ b/drivers/hid/hid-logitech-dj.c
@@ -1035,7 +1035,7 @@ static void logi_dj_recv_forward_null_report(struct dj_receiver_dev *djrcv_dev,
 	memset(reportbuffer, 0, sizeof(reportbuffer));
 
 	for (i = 0; i < NUMBER_OF_HID_REPORTS; i++) {
-		if (djdev->reports_supported & (1 << i)) {
+		if (djdev->reports_supported & BIT_ULL(i)) {
 			reportbuffer[0] = i;
 			if (hid_input_report(djdev->hdev,
 					     HID_INPUT_REPORT,
-- 
2.29.2