From: Colin Ian King <colin.king@canonical.com>
Date: Tue, 30 Jun 2020 15:55:58 +0100
Subject: thunderbolt: Ensure left shift of 512 does not overflow a 32 bit int
Git-commit: 4c767ce48cf858971545164c4c53d028e6241c07
Patch-mainline: v5.9-rc1
References: jsc#SLE-14130
The 32 bit int value 512 is being left shifted and then used in a context
that expects the expression to be a larger unsigned long. There may be
a potential integer overflow, so make 512 a UL before shift to avoid
any such issues.
Addresses-Coverity: ("Uninintentional integer overflow")
Fixes: 3b1d8d577ca8 ("thunderbolt: Implement USB3 bandwidth negotiation routines")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---
drivers/thunderbolt/usb4.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 966f334b4010..2b8355e6b65f 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -1368,7 +1368,7 @@ static unsigned int usb3_bw_to_mbps(u32 bw, u8 scale)
{
unsigned long uframes;
- uframes = bw * 512 << scale;
+ uframes = bw * 512UL << scale;
return DIV_ROUND_CLOSEST(uframes * 8000, 1000 * 1000);
}
@@ -1378,7 +1378,7 @@ static u32 mbps_to_usb3_bw(unsigned int mbps, u8 scale)
/* 1 uframe is 1/8 ms (125 us) -> 1 / 8000 s */
uframes = ((unsigned long)mbps * 1000 * 1000) / 8000;
- return DIV_ROUND_UP(uframes, 512 << scale);
+ return DIV_ROUND_UP(uframes, 512UL << scale);
}
static int usb4_usb3_port_read_allocated_bandwidth(struct tb_port *port,