Commit 73f88592 authored by Tavian Barnes's avatar Tavian Barnes Committed by Kent Overstreet
Browse files

bcachefs: mean_and_variance: Avoid too-large shift amounts 



Shifting a value by the width of its type or more is undefined.

Signed-off-by: default avatarTavian Barnes <tavianator@tavianator.com>
Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent a97b43fa

fs/bcachefs/mean_and_variance.h

+3 −3
Original line number Diff line number Diff line
@@ -111,11 +111,11 @@ static inline u128_u u128_shl(u128_u i, s8 shift) 
{

	u128_u r;



	r.lo = i.lo << shift;

	r.lo = i.lo << (shift & 63);

	if (shift < 64)

		r.hi = (i.hi << shift) | (i.lo >> (64 - shift));

		r.hi = (i.hi << (shift & 63)) | (i.lo >> (-shift & 63));

	else {

		r.hi = i.lo << (shift - 64);

		r.hi = i.lo << (-shift & 63);

		r.lo = 0;

	}

	return r;