[PATCH v3 1/6] regulator: core: validate selector against linear_min_sel

[Claudiu Beznea]

There are regulators who's min selector is not zero. Selectors loops
(looping b/w zero and regulator::desc::n_voltages) might throw errors
because invalid selectors are used (lower than
regulator::desc::linear_min_sel). For this situations validate selectors
against regulator::desc::linear_min_sel.

Fixes: 3a40cfc36bb3d ("regulator: core: create unlocked version of 
regulator_list_voltage")
Fixes: 04eca28cde52c ("regulator: Add helpers for low-level register access")
Fixes: 88cd222b259d6 ("regulator: provide consumer interface for fall/rise 
time")
Fixes: d295f7670127e ("regulator: core: Move 
list_voltage_{linear,linear_range,table} to helpers.c")
Signed-off-by: Claudiu Beznea <claudiu.bez...@microchip.com>
---
 drivers/regulator/core.c    | 9 +++++++--
 drivers/regulator/helpers.c | 3 ++-
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 2e1ea18221ef..1d0d35f14f37 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2958,7 +2958,8 @@ static int _regulator_list_voltage(struct regulator_dev 
*rdev,
                return rdev->desc->fixed_uV;
 
        if (ops->list_voltage) {
-               if (selector >= rdev->desc->n_voltages)
+               if (selector >= rdev->desc->n_voltages ||
+                   selector < rdev->desc->linear_min_sel)
                        return -EINVAL;
                if (lock)
                        regulator_lock(rdev);
@@ -3109,7 +3110,8 @@ int regulator_list_hardware_vsel(struct regulator 
*regulator,
        struct regulator_dev *rdev = regulator->rdev;
        const struct regulator_ops *ops = rdev->desc->ops;
 
-       if (selector >= rdev->desc->n_voltages)
+       if (selector >= rdev->desc->n_voltages ||
+           selector < rdev->desc->linear_min_sel)
                return -EINVAL;
        if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
                return -EOPNOTSUPP;
@@ -4032,6 +4034,9 @@ int regulator_set_voltage_time(struct regulator 
*regulator,
 
        for (i = 0; i < rdev->desc->n_voltages; i++) {
                /* We only look for exact voltage matches here */
+               if (i < rdev->desc->linear_min_sel)
+                       continue;
+
                voltage = regulator_list_voltage(regulator, i);
                if (voltage < 0)
                        return -EINVAL;
diff --git a/drivers/regulator/helpers.c b/drivers/regulator/helpers.c
index e4bb09bbd3fa..974f1a63993d 100644
--- a/drivers/regulator/helpers.c
+++ b/drivers/regulator/helpers.c
@@ -647,7 +647,8 @@ int regulator_list_voltage_table(struct regulator_dev *rdev,
                return -EINVAL;
        }
 
-       if (selector >= rdev->desc->n_voltages)
+       if (selector >= rdev->desc->n_voltages ||
+           selector < rdev->desc->linear_min_sel)
                return -EINVAL;
 
        return rdev->desc->volt_table[selector];
-- 
2.7.4