From: Colin Ian King <colin.k...@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.k...@canonical.com>
Link: https://lore.kernel.org/r/20201105112427.40688-1-colin.k...@canonical.com
Signed-off-by: Marc Kleine-Budde <m...@pengutronix.de>
Signed-off-by: Sasha Levin <sas...@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



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