| Message ID | 20230128005358.never.313-kees@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e314e15a0b58f9d051c00b25951073bcdae61953 |
| Headers | show |
| Series | regulator: s5m8767: Bounds check id indexing into arrays | expand |
On 28/01/2023 01:53, Kees Cook wrote: > The compiler has no way to know if "id" is within the array bounds of It has. For the CONFIG_OF (the only way parent device - sec-core.c - can match now), the id is assigned in s5m8767_pmic_dt_parse_pdata() and kept within limits <0,ARRAY_SIZE(regulators)-1>. The device cannot match via old non-OF way, so there is no real bug to fix. You are silencing compiler warning, which is fine, but it's not a real case. The code is not easy to follow, so I am fine with such checks (WARN_ON_ONCE). The BUILD_BUG_ON is indeed meaningful. Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Best regards, Krzysztof
On Fri, 27 Jan 2023 16:53:58 -0800, Kees Cook wrote: > The compiler has no way to know if "id" is within the array bounds of > the regulators array. Add a check for this and a build-time check that > the regulators and reg_voltage_map arrays are sized the same. Seen with > GCC 13: > > ../drivers/regulator/s5m8767.c: In function 's5m8767_pmic_probe': > ../drivers/regulator/s5m8767.c:936:35: warning: array subscript [0, 36] is outside array bounds of 'struct regulator_desc[37]' [-Warray-bounds=] > 936 | regulators[id].vsel_reg = > | ~~~~~~~~~~^~~~ > > [...] Applied to broonie/regulator.git for-next Thanks! [1/1] regulator: s5m8767: Bounds check id indexing into arrays commit: e314e15a0b58f9d051c00b25951073bcdae61953 All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark
diff --git a/drivers/regulator/s5m8767.c b/drivers/regulator/s5m8767.c index 35269f998210..754c6fcc6e64 100644 --- a/drivers/regulator/s5m8767.c +++ b/drivers/regulator/s5m8767.c @@ -923,10 +923,14 @@ static int s5m8767_pmic_probe(struct platform_device *pdev) for (i = 0; i < pdata->num_regulators; i++) { const struct sec_voltage_desc *desc; - int id = pdata->regulators[i].id; + unsigned int id = pdata->regulators[i].id; int enable_reg, enable_val; struct regulator_dev *rdev; + BUILD_BUG_ON(ARRAY_SIZE(regulators) != ARRAY_SIZE(reg_voltage_map)); + if (WARN_ON_ONCE(id >= ARRAY_SIZE(regulators))) + continue; + desc = reg_voltage_map[id]; if (desc) { regulators[id].n_voltages =
The compiler has no way to know if "id" is within the array bounds of the regulators array. Add a check for this and a build-time check that the regulators and reg_voltage_map arrays are sized the same. Seen with GCC 13: ../drivers/regulator/s5m8767.c: In function 's5m8767_pmic_probe': ../drivers/regulator/s5m8767.c:936:35: warning: array subscript [0, 36] is outside array bounds of 'struct regulator_desc[37]' [-Warray-bounds=] 936 | regulators[id].vsel_reg = | ~~~~~~~~~~^~~~ Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: linux-samsung-soc@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/regulator/s5m8767.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)