patch "slimbus: Fix out-of-bounds access in slim_slicesize()" added to char-misc-linus

This is a note to let you know that I've just added the patch titled

slimbus: Fix out-of-bounds access in slim_slicesize()

to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From: Geert Uytterhoeven <[email protected]>
Date: Sun, 8 Apr 2018 11:02:34 +0200
Subject: slimbus: Fix out-of-bounds access in slim_slicesize()
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With gcc-4.1.2:

slimbus/messaging.c: In function ‘slim_slicesize’:
slimbus/messaging.c:186: warning: statement with no effect

Indeed, clamp() is a macro not operating in-place, but returning the clamped value. Hence the value is not clamped at all, which may lead to an out-of-bounds access.

Fix this by assigning the clamped value.

---
 drivers/slimbus/messaging.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 884419c37e84..457ea1f8db30 100644
@@ -183,7 +183,7 @@ static u16 slim_slicesize(int code)
 		0, 1, 2, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 7
 	};
 
-	clamp(code, 1, (int)ARRAY_SIZE(sizetocode));
+	code = clamp(code, 1, (int)ARRAY_SIZE(sizetocode));
 
 	return sizetocode[code - 1];
 }

2.17.0