From 4dab0fd40323f55c94c2377cf29aaac1b4408176 Mon Sep 17 00:00:00 2001 From: Peter Chen Date: Thu, 22 Oct 2020 08:55:03 +0800 Subject: usb: cdns3: gadget: suspicious implicit sign extension [ Upstream commit 5fca3f062879f8e5214c56f3e3e2be6727900f5d ] The code: trb->length = cpu_to_le32(TRB_BURST_LEN(priv_ep->trb_burst_size) | TRB_LEN(length)); TRB_BURST_LEN(priv_ep->trb_burst_size) may be overflow for int 32 if priv_ep->trb_burst_size is equal or larger than 0x80; Below is the Coverity warning: sign_extension: Suspicious implicit sign extension: priv_ep->trb_burst_size with type u8 (8 bits, unsigned) is promoted in priv_ep->trb_burst_size << 24 to type int (32 bits, signed), then sign-extended to type unsigned long (64 bits, unsigned). If priv_ep->trb_burst_size << 24 is greater than 0x7FFFFFFF, the upper bits of the result will all be 1. To fix it, it needs to add an explicit cast to unsigned int type for ((p) << 24). Reviewed-by: Jun Li Signed-off-by: Peter Chen Signed-off-by: Sasha Levin --- drivers/usb/cdns3/gadget.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/cdns3/gadget.h b/drivers/usb/cdns3/gadget.h index bc4024041ef2..ec5c05454531 100644 --- a/drivers/usb/cdns3/gadget.h +++ b/drivers/usb/cdns3/gadget.h @@ -1057,7 +1057,7 @@ struct cdns3_trb { #define TRB_TDL_SS_SIZE_GET(p) (((p) & GENMASK(23, 17)) >> 17) /* transfer_len bitmasks - bits 31:24 */ -#define TRB_BURST_LEN(p) (((p) << 24) & GENMASK(31, 24)) +#define TRB_BURST_LEN(p) ((unsigned int)((p) << 24) & GENMASK(31, 24)) #define TRB_BURST_LEN_GET(p) (((p) & GENMASK(31, 24)) >> 24) /* Data buffer pointer bitmasks*/ -- cgit v1.2.3