[PATCH] clk: s2mps11: initialise clk_hw_onecell_data::num before accessing ::hws[] in probe()
From: André Draszik
Date: Wed Mar 26 2025 - 08:08:21 EST
With UBSAN enabled, we're getting the following trace:
UBSAN: array-index-out-of-bounds in .../drivers/clk/clk-s2mps11.c:186:3
index 0 is out of range for type 'struct clk_hw *[] __counted_by(num)' (aka 'struct clk_hw *[]')
This is because commit f316cdff8d67 ("clk: Annotate struct
clk_hw_onecell_data with __counted_by") annotated the hws member of
that struct with __counted_by, which informs the bounds sanitizer about
the number of elements in hws, so that it can warn when hws is accessed
out of bounds.
As noted in that change, the __counted_by member must be initialised
with the number of elements before the first array access happens,
otherwise there will be a warning from each access prior to the
initialisation because the number of elements is zero. This occurs in
s2mps11_clk_probe() due to ::num being assigned after ::hws access.
Move the assignment to satisfy the requirement of assign-before-access.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by")
Signed-off-by: André Draszik <andre.draszik@xxxxxxxxxx>
---
drivers/clk/clk-s2mps11.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/clk-s2mps11.c b/drivers/clk/clk-s2mps11.c
index 014db6386624071e173b5b940466301d2596400a..8ddf3a9a53dfd5bb52a05a3e02788a357ea77ad3 100644
--- a/drivers/clk/clk-s2mps11.c
+++ b/drivers/clk/clk-s2mps11.c
@@ -137,6 +137,8 @@ static int s2mps11_clk_probe(struct platform_device *pdev)
if (!clk_data)
return -ENOMEM;
+ clk_data->num = S2MPS11_CLKS_NUM;
+
switch (hwid) {
case S2MPS11X:
s2mps11_reg = S2MPS11_REG_RTC_CTRL;
@@ -186,7 +188,6 @@ static int s2mps11_clk_probe(struct platform_device *pdev)
clk_data->hws[i] = &s2mps11_clks[i].hw;
}
- clk_data->num = S2MPS11_CLKS_NUM;
of_clk_add_hw_provider(s2mps11_clks->clk_np, of_clk_hw_onecell_get,
clk_data);
---
base-commit: 9388ec571cb1adba59d1cded2300eeb11827679c
change-id: 20250326-s2mps11-ubsan-c90978e7bc04
Best regards,
--
André Draszik <andre.draszik@xxxxxxxxxx>