| From 337dd9f6e316658684e2f58a3144599bf29c6ce1 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 5 Nov 2020 11:24:27 +0000 |
| Subject: can: peak_usb: fix potential integer overflow on shift of a int |
| |
| From: Colin Ian King <colin.king@canonical.com> |
| |
| [ Upstream commit 8a68cc0d690c9e5730d676b764c6f059343b842c ] |
| |
| The left shift of int 32 bit integer constant 1 is evaluated using 32 bit |
| arithmetic and then assigned to a signed 64 bit variable. In the case where |
| time_ref->adapter->ts_used_bits is 32 or more this can lead to an oveflow. |
| Avoid this by shifting using the BIT_ULL macro instead. |
| |
| Fixes: bb4785551f64 ("can: usb: PEAK-System Technik USB adapters driver core") |
| Signed-off-by: Colin Ian King <colin.king@canonical.com> |
| Link: https://lore.kernel.org/r/20201105112427.40688-1-colin.king@canonical.com |
| Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/net/can/usb/peak_usb/pcan_usb_core.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_core.c b/drivers/net/can/usb/peak_usb/pcan_usb_core.c |
| index db156a11e6db5..f7d653d48a1e4 100644 |
| --- a/drivers/net/can/usb/peak_usb/pcan_usb_core.c |
| +++ b/drivers/net/can/usb/peak_usb/pcan_usb_core.c |
| @@ -164,7 +164,7 @@ void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time) |
| if (time_ref->ts_dev_1 < time_ref->ts_dev_2) { |
| /* case when event time (tsw) wraps */ |
| if (ts < time_ref->ts_dev_1) |
| - delta_ts = 1 << time_ref->adapter->ts_used_bits; |
| + delta_ts = BIT_ULL(time_ref->adapter->ts_used_bits); |
| |
| /* Otherwise, sync time counter (ts_dev_2) has wrapped: |
| * handle case when event time (tsn) hasn't. |
| @@ -176,7 +176,7 @@ void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time) |
| * tsn ts |
| */ |
| } else if (time_ref->ts_dev_1 < ts) { |
| - delta_ts = -(1 << time_ref->adapter->ts_used_bits); |
| + delta_ts = -BIT_ULL(time_ref->adapter->ts_used_bits); |
| } |
| |
| /* add delay between last sync and event timestamps */ |
| -- |
| 2.27.0 |
| |
