From: Maud Spierings maudspierings@gocontroll.com

Throughout the various probe functions &indio_dev->dev is used before it is initialized. This caused a kernel panic in st_sensors_power_enable() when the call to devm_regulator_bulk_get_enable() fails and then calls dev_err_probe() with the uninitialized device.

This seems to only cause a panic with dev_err_probe(), dev_err(), dev_warn() and dev_info() don't seem to cause a panic, but are fixed as well.

The issue is reported and traced here: [1]

[1]: https://lore.kernel.org/all/AM7P189MB100986A83D2F28AF3FFAF976E39EA@AM7P189MB...

Cc: stable@vger.kernel.org Signed-off-by: Maud Spierings maudspierings@gocontroll.com --- When I search for general &indio_dev->dev usage, I see quite a lot more hits, but I am not sure if there are issues with those too.

This issue has existed for a long time it seems and therefore it is nearly impossible to find a proper fixes tag. I would love to see it at least backported to 6.12 as that is where I encountered it, and I believe the patch should apply without conflicts. --- Changes in v3: - Added the stable cc to the commit message - Move the link to the original issue to the commit message - Fix function notation in the commit message - Move some more of the dev_*() calls to one line - Link to v2: https://lore.kernel.org/r/20250522-st_iio_fix-v2-1-07a32655a996@gocontroll.c...

Changes in v2: - Added SoB in commit message - Link to v1: https://lore.kernel.org/r/20250522-st_iio_fix-v1-1-d689b35f1612@gocontroll.c... --- drivers/iio/accel/st_accel_core.c | 10 +++--- drivers/iio/common/st_sensors/st_sensors_core.c | 36 ++++++++++------------ drivers/iio/common/st_sensors/st_sensors_trigger.c | 20 ++++++------ 3 files changed, 31 insertions(+), 35 deletions(-)

diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c index 99cb661fabb2d9cc1943fa8d0a6f3becb71126e6..a7961c610ed203d039bbf298c8883031a578fb0b 100644 --- a/drivers/iio/accel/st_accel_core.c +++ b/drivers/iio/accel/st_accel_core.c @@ -1353,6 +1353,7 @@ static int apply_acpi_orientation(struct iio_dev *indio_dev) union acpi_object *ont; union acpi_object *elements; acpi_status status; + struct device *parent = indio_dev->dev.parent; int ret = -EINVAL; unsigned int val; int i, j; @@ -1371,7 +1372,7 @@ static int apply_acpi_orientation(struct iio_dev *indio_dev) };

- adev = ACPI_COMPANION(indio_dev->dev.parent); + adev = ACPI_COMPANION(parent); if (!adev) return -ENXIO;

@@ -1380,8 +1381,7 @@ static int apply_acpi_orientation(struct iio_dev *indio_dev) if (status == AE_NOT_FOUND) { return -ENXIO; } else if (ACPI_FAILURE(status)) { - dev_warn(&indio_dev->dev, "failed to execute _ONT: %d\n", - status); + dev_warn(parent, "failed to execute _ONT: %d\n", status); return status; }

@@ -1457,12 +1457,12 @@ static int apply_acpi_orientation(struct iio_dev *indio_dev) }

ret = 0; - dev_info(&indio_dev->dev, "computed mount matrix from ACPI\n"); + dev_info(parent, "computed mount matrix from ACPI\n");

out: kfree(buffer.pointer); if (ret) - dev_dbg(&indio_dev->dev, + dev_dbg(parent, "failed to apply ACPI orientation data: %d\n", ret);

return ret; diff --git a/drivers/iio/common/st_sensors/st_sensors_core.c b/drivers/iio/common/st_sensors/st_sensors_core.c index 8ce1dccfea4f5aaff45d3d40f6542323dd1f0b09..dac593be56958fd0be92e13f628350fcfd0f040d 100644 --- a/drivers/iio/common/st_sensors/st_sensors_core.c +++ b/drivers/iio/common/st_sensors/st_sensors_core.c @@ -154,7 +154,7 @@ static int st_sensors_set_fullscale(struct iio_dev *indio_dev, unsigned int fs) return err;

st_accel_set_fullscale_error: - dev_err(&indio_dev->dev, "failed to set new fullscale.\n"); + dev_err(indio_dev->dev.parent, "failed to set new fullscale.\n"); return err; }

@@ -231,8 +231,7 @@ int st_sensors_power_enable(struct iio_dev *indio_dev) ARRAY_SIZE(regulator_names), regulator_names); if (err) - return dev_err_probe(&indio_dev->dev, err, - "unable to enable supplies\n"); + return dev_err_probe(parent, err, "unable to enable supplies\n");

return 0; } @@ -241,13 +240,14 @@ EXPORT_SYMBOL_NS(st_sensors_power_enable, "IIO_ST_SENSORS"); static int st_sensors_set_drdy_int_pin(struct iio_dev *indio_dev, struct st_sensors_platform_data *pdata) { + struct device *parent = indio_dev->dev.parent; struct st_sensor_data *sdata = iio_priv(indio_dev);

/* Sensor does not support interrupts */ if (!sdata->sensor_settings->drdy_irq.int1.addr && !sdata->sensor_settings->drdy_irq.int2.addr) { if (pdata->drdy_int_pin) - dev_info(&indio_dev->dev, + dev_info(parent, "DRDY on pin INT%d specified, but sensor does not support interrupts\n", pdata->drdy_int_pin); return 0; @@ -256,29 +256,27 @@ static int st_sensors_set_drdy_int_pin(struct iio_dev *indio_dev, switch (pdata->drdy_int_pin) { case 1: if (!sdata->sensor_settings->drdy_irq.int1.mask) { - dev_err(&indio_dev->dev, - "DRDY on INT1 not available.\n"); + dev_err(parent, "DRDY on INT1 not available.\n"); return -EINVAL; } sdata->drdy_int_pin = 1; break; case 2: if (!sdata->sensor_settings->drdy_irq.int2.mask) { - dev_err(&indio_dev->dev, - "DRDY on INT2 not available.\n"); + dev_err(parent, "DRDY on INT2 not available.\n"); return -EINVAL; } sdata->drdy_int_pin = 2; break; default: - dev_err(&indio_dev->dev, "DRDY on pdata not valid.\n"); + dev_err(parent, "DRDY on pdata not valid.\n"); return -EINVAL; }

if (pdata->open_drain) { if (!sdata->sensor_settings->drdy_irq.int1.addr_od && !sdata->sensor_settings->drdy_irq.int2.addr_od) - dev_err(&indio_dev->dev, + dev_err(parent, "open drain requested but unsupported.\n"); else sdata->int_pin_open_drain = true; @@ -336,6 +334,7 @@ EXPORT_SYMBOL_NS(st_sensors_dev_name_probe, "IIO_ST_SENSORS"); int st_sensors_init_sensor(struct iio_dev *indio_dev, struct st_sensors_platform_data *pdata) { + struct device *parent = indio_dev->dev.parent; struct st_sensor_data *sdata = iio_priv(indio_dev); struct st_sensors_platform_data *of_pdata; int err = 0; @@ -343,7 +342,7 @@ int st_sensors_init_sensor(struct iio_dev *indio_dev, mutex_init(&sdata->odr_lock);

/* If OF/DT pdata exists, it will take precedence of anything else */ - of_pdata = st_sensors_dev_probe(indio_dev->dev.parent, pdata); + of_pdata = st_sensors_dev_probe(parent, pdata); if (IS_ERR(of_pdata)) return PTR_ERR(of_pdata); if (of_pdata) @@ -370,7 +369,7 @@ int st_sensors_init_sensor(struct iio_dev *indio_dev, if (err < 0) return err; } else - dev_info(&indio_dev->dev, "Full-scale not possible\n"); + dev_info(parent, "Full-scale not possible\n");

err = st_sensors_set_odr(indio_dev, sdata->odr); if (err < 0) @@ -405,7 +404,7 @@ int st_sensors_init_sensor(struct iio_dev *indio_dev, mask = sdata->sensor_settings->drdy_irq.int2.mask_od; }

- dev_info(&indio_dev->dev, + dev_info(parent, "set interrupt line to open drain mode on pin %d\n", sdata->drdy_int_pin); err = st_sensors_write_data_with_mask(indio_dev, addr, @@ -593,21 +592,20 @@ EXPORT_SYMBOL_NS(st_sensors_get_settings_index, "IIO_ST_SENSORS"); int st_sensors_verify_id(struct iio_dev *indio_dev) { struct st_sensor_data *sdata = iio_priv(indio_dev); + struct device *parent = indio_dev->dev.parent; int wai, err;

if (sdata->sensor_settings->wai_addr) { err = regmap_read(sdata->regmap, sdata->sensor_settings->wai_addr, &wai); if (err < 0) { - dev_err(&indio_dev->dev, - "failed to read Who-Am-I register.\n"); - return err; + return dev_err_probe(parent, err, + "failed to read Who-Am-I register.\n"); }

if (sdata->sensor_settings->wai != wai) { - dev_warn(&indio_dev->dev, - "%s: WhoAmI mismatch (0x%x).\n", - indio_dev->name, wai); + dev_warn(parent, "%s: WhoAmI mismatch (0x%x).\n", + indio_dev->name, wai); } }

diff --git a/drivers/iio/common/st_sensors/st_sensors_trigger.c b/drivers/iio/common/st_sensors/st_sensors_trigger.c index 9d4bf822a15dfcdd6c2835f6b9d7698cd3cb0b08..8a8ab688d7980f6dd43c660f90a0eba32c38388b 100644 --- a/drivers/iio/common/st_sensors/st_sensors_trigger.c +++ b/drivers/iio/common/st_sensors/st_sensors_trigger.c @@ -127,7 +127,7 @@ int st_sensors_allocate_trigger(struct iio_dev *indio_dev, sdata->trig = devm_iio_trigger_alloc(parent, "%s-trigger", indio_dev->name); if (sdata->trig == NULL) { - dev_err(&indio_dev->dev, "failed to allocate iio trigger.\n"); + dev_err(parent, "failed to allocate iio trigger.\n"); return -ENOMEM; }

@@ -143,7 +143,7 @@ int st_sensors_allocate_trigger(struct iio_dev *indio_dev, case IRQF_TRIGGER_FALLING: case IRQF_TRIGGER_LOW: if (!sdata->sensor_settings->drdy_irq.addr_ihl) { - dev_err(&indio_dev->dev, + dev_err(parent, "falling/low specified for IRQ but hardware supports only rising/high: will request rising/high\n"); if (irq_trig == IRQF_TRIGGER_FALLING) irq_trig = IRQF_TRIGGER_RISING; @@ -156,21 +156,19 @@ int st_sensors_allocate_trigger(struct iio_dev *indio_dev, sdata->sensor_settings->drdy_irq.mask_ihl, 1); if (err < 0) return err; - dev_info(&indio_dev->dev, + dev_info(parent, "interrupts on the falling edge or active low level\n"); } break; case IRQF_TRIGGER_RISING: - dev_info(&indio_dev->dev, - "interrupts on the rising edge\n"); + dev_info(parent, "interrupts on the rising edge\n"); break; case IRQF_TRIGGER_HIGH: - dev_info(&indio_dev->dev, - "interrupts active high level\n"); + dev_info(parent, "interrupts active high level\n"); break; default: /* This is the most preferred mode, if possible */ - dev_err(&indio_dev->dev, + dev_err(parent, "unsupported IRQ trigger specified (%lx), enforce rising edge\n", irq_trig); irq_trig = IRQF_TRIGGER_RISING; } @@ -179,7 +177,7 @@ int st_sensors_allocate_trigger(struct iio_dev *indio_dev, if (irq_trig == IRQF_TRIGGER_FALLING || irq_trig == IRQF_TRIGGER_RISING) { if (!sdata->sensor_settings->drdy_irq.stat_drdy.addr) { - dev_err(&indio_dev->dev, + dev_err(parent, "edge IRQ not supported w/o stat register.\n"); return -EOPNOTSUPP; } @@ -214,13 +212,13 @@ int st_sensors_allocate_trigger(struct iio_dev *indio_dev, sdata->trig->name, sdata->trig); if (err) { - dev_err(&indio_dev->dev, "failed to request trigger IRQ.\n"); + dev_err(parent, "failed to request trigger IRQ.\n"); return err; }

err = devm_iio_trigger_register(parent, sdata->trig); if (err < 0) { - dev_err(&indio_dev->dev, "failed to register iio trigger.\n"); + dev_err(parent, "failed to register iio trigger.\n"); return err; } indio_dev->trig = iio_trigger_get(sdata->trig);

--- base-commit: 7bac2c97af4078d7a627500c9bcdd5b033f97718 change-id: 20250522-st_iio_fix-1c58fdd4d420

Best regards,