[PATCH] clk: mstar: msc313-mpll: fix off-by-one in clock array allocation

From: hanzhijian

Date: Fri Aug 21 2026 - 19:59:01 EST


The hws array of mpll->clk_data is allocated with struct_size() using
ARRAY_SIZE(output_dividers) as the element count, giving it 7 elements.
But the probe function stores the MPLL clock at hws[0] and one
fixed-factor clock for each output divider at hws[i + 1] for i in
[0, ARRAY_SIZE(output_dividers)), writing 8 elements in total. The
final write to hws[7] is past the end of the allocation.

clk_data->num is also set to NUMOUTPUTS (8), so the clock framework
reads hws[0..7], again accessing hws[7] out of bounds.

Use NUMOUTPUTS as the element count so the allocation matches the
number of clocks actually stored and exposed.

Found by smatch:
drivers/clk/mstar/clk-msc313-mpll.c:134 msc313_mpll_probe()
error: buffer overflow 'mpll->clk_data->hws' 7 <= 7

Signed-off-by: hanzhijian <hanzhijian1991@xxxxxxxxx>
---
drivers/clk/mstar/clk-msc313-mpll.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/mstar/clk-msc313-mpll.c b/drivers/clk/mstar/clk-msc313-mpll.c
index 61beb4e87..bd45aa0ae 100644
--- a/drivers/clk/mstar/clk-msc313-mpll.c
+++ b/drivers/clk/mstar/clk-msc313-mpll.c
@@ -105,7 +105,7 @@ static int msc313_mpll_probe(struct platform_device *pdev)
return PTR_ERR(mpll->loop_div_second);

mpll->clk_data = devm_kzalloc(dev, struct_size(mpll->clk_data, hws,
- ARRAY_SIZE(output_dividers)), GFP_KERNEL);
+ NUMOUTPUTS), GFP_KERNEL);
if (!mpll->clk_data)
return -ENOMEM;

--
2.43.0