Messages in this thread | | | Date | Wed, 7 May 2014 18:50:35 +0200 | From | Maxime Coquelin <> | Subject | Re: [PATCH] clk: divider: Fix overflow in clk_divider_bestdiv |
| |
Hi Tomasz,
On 05/07/2014 06:24 PM, Tomasz Figa wrote: > Commit c686078 ("clk: divider: Add round to closest divider") introduced > a helper function to check whether given divisor is the best one instead > of direct check. However due to int type used instead of unsigned long > for passing calculated rates to this function in certain cases an > overflow could occur, for example when trying to obtain maximum possible > clock rate by calling clk_round_rate(..., UINT_MAX). > > This patch fixes this issue by changing the type of rate, now and best > arguments of the function to unsigned long, which is the type that > should be used for clock rates. Good catch.
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
Thanks, Maxime > > Signed-off-by: Tomasz Figa <t.figa@samsung.com> > --- > drivers/clk/clk-divider.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c > index c572945..e0b360a 100644 > --- a/drivers/clk/clk-divider.c > +++ b/drivers/clk/clk-divider.c > @@ -232,7 +232,7 @@ static int _div_round(struct clk_divider *divider, unsigned long parent_rate, > } > > static bool _is_best_div(struct clk_divider *divider, > - int rate, int now, int best) > + unsigned long rate, unsigned long now, unsigned long best) > { > if (divider->flags & CLK_DIVIDER_ROUND_CLOSEST) > return abs(rate - now) < abs(rate - best); >
| |