| Message ID | 20250326-s2mps11-ubsan-v1-1-fcc6fce5c8a9@linaro.org (mailing list archive) |
|---|---|
| State | Under Review |
| Headers | show |
| Series | clk: s2mps11: initialise clk_hw_onecell_data::num before accessing ::hws[] in probe() | expand |
On 26/03/2025 13:08, André Draszik wrote: > 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. > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Best regards, Krzysztof
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);
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@vger.kernel.org Fixes: f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by") Signed-off-by: André Draszik <andre.draszik@linaro.org> --- drivers/clk/clk-s2mps11.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- base-commit: 9388ec571cb1adba59d1cded2300eeb11827679c change-id: 20250326-s2mps11-ubsan-c90978e7bc04 Best regards,