From 4c767ce48cf858971545164c4c53d028e6241c07 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Tue, 30 Jun 2020 15:55:58 +0100 Subject: [PATCH] thunderbolt: Ensure left shift of 512 does not overflow a 32 bit int 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 Signed-off-by: Mika Westerberg --- 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 966f334..2b8355e 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, -- 2.7.4