[S] Change in flashrom[master]: ps25f.c: Fix UB on shift

[Evan Benn (Code Review)]

Attention is currently required from: Nikolai Artemiev.

Hello Nikolai Artemiev,

I'd like you to do a code review.
Please visit

https://review.coreboot.org/c/flashrom/+/68127

to review the following change.

Change subject: ps25f.c: Fix UB on shift
......................................................................

ps25f.c: Fix UB on shift

dev_id, a u8, was shifted left 24. After promotion to int, this results
in shifting into the sign bit, which is undefined behaviour. Cast to
uint32 to prevent the promotion to signed int.

BUG=None
BRANCH=None
TEST=None

Change-Id: I88188ef2ba2af919eeae9ba08916374d31d8b989
Signed-off-by: Evan Benn 
---
M s25f.c
1 file changed, 22 insertions(+), 4 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/27/68127/1

diff --git a/s25f.c b/s25f.c
index 67715ed..1133ef8 100644
--- a/s25f.c
+++ b/s25f.c
@@ -380,10 +380,10 @@
     */

uint32_t model_id =
-		dev_id[1] << 24 |
-		dev_id[2] << 16 |
-		dev_id[4] << 8  |
-		dev_id[5] << 0;
+		(uint32_t)dev_id[1] << 24 |
+		(uint32_t)dev_id[2] << 16 |
+		(uint32_t)dev_id[4] << 8  |
+		(uint32_t)dev_id[5] << 0;

if (dev_id[0] == flash->chip->manufacture_id && model_id == flash->chip->model_id)
    	return 1;