2019-03-30 01:25:58

by Xiaoming Ni

[permalink] [raw]
Subject: [PATCH v2] clk:mmp: clk-mix.c fix divide-by-zero

The _get_div function has a branch with a return value of 0
Add a check on the return value of _get_div to avoid divide-by-zero

Signed-off-by: nixiaoming <[email protected]>
Reviewed-by: Mukesh Ojha <[email protected]>
---
drivers/clk/mmp/clk-mix.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/clk/mmp/clk-mix.c b/drivers/clk/mmp/clk-mix.c
index 90814b2..6ed5ad7 100644
--- a/drivers/clk/mmp/clk-mix.c
+++ b/drivers/clk/mmp/clk-mix.c
@@ -245,6 +245,9 @@ static int mmp_clk_mix_determine_rate(struct clk_hw *hw,
div_val_max = _get_maxdiv(mix);
for (j = 0; j < div_val_max; j++) {
div = _get_div(mix, j);
+ /* avoid divide-by-zero */
+ if (!div)
+ continue;
mix_rate = parent_rate / div;
gap = abs(mix_rate - req->rate);
if (!parent_best || gap < gap_best) {
@@ -341,6 +344,9 @@ static unsigned long mmp_clk_mix_recalc_rate(struct clk_hw *hw,
shift = mix->reg_info.shift_div;

div = _get_div(mix, MMP_CLK_BITS_GET_VAL(mux_div, width, shift));
+ /* avoid divide-by-zero */
+ if (!div)
+ return -EINVAL;

return parent_rate / div;
}
--
1.8.5.6