| Message ID | 20250528194425.567172-2-krzysztof.kozlowski@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | leds: flash: leds-qcom-flash: Fix registry access after re-bind | expand |
On 5/29/2025 3:44 AM, Krzysztof Kozlowski wrote: > Driver in probe() updates each of 'reg_field' with 'reg_base': > > for (i = 0; i < REG_MAX_COUNT; i++) > regs[i].reg += reg_base; > > 'reg_field' array (under variable 'regs' above) is statically allocated, > this each re-bind would add another 'reg_base' leading to bogus > register addresses. Constify the local 'reg_field' array and duplicate > it in probe to solve this. > > Fixes: 96a2e242a5dc ("leds: flash: Add driver to support flash LED module in QCOM PMICs") > Cc: <stable@vger.kernel.org> > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> > > --- > > This is a nice example why constifying static memory is useful. Thanks for fixing it! > --- > drivers/leds/flash/leds-qcom-flash.c | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/drivers/leds/flash/leds-qcom-flash.c b/drivers/leds/flash/leds-qcom-flash.c > index b4c19be51c4d..b8a48c15d797 100644 > --- a/drivers/leds/flash/leds-qcom-flash.c > +++ b/drivers/leds/flash/leds-qcom-flash.c > @@ -117,7 +117,7 @@ enum { > REG_MAX_COUNT, > }; > > -static struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = { > +static const struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = { > REG_FIELD(0x08, 0, 7), /* status1 */ > REG_FIELD(0x09, 0, 7), /* status2 */ > REG_FIELD(0x0a, 0, 7), /* status3 */ > @@ -132,7 +132,7 @@ static struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = { > REG_FIELD(0x58, 0, 2), /* therm_thrsh3 */ > }; > > -static struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = { > +static const struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = { > REG_FIELD(0x06, 0, 7), /* status1 */ > REG_FIELD(0x07, 0, 6), /* status2 */ > REG_FIELD(0x09, 0, 7), /* status3 */ > @@ -854,11 +854,17 @@ static int qcom_flash_led_probe(struct platform_device *pdev) > if (val == FLASH_SUBTYPE_3CH_PM8150_VAL || val == FLASH_SUBTYPE_3CH_PMI8998_VAL) { > flash_data->hw_type = QCOM_MVFLASH_3CH; > flash_data->max_channels = 3; > - regs = mvflash_3ch_regs; > + regs = devm_kmemdup(dev, mvflash_3ch_regs, sizeof(mvflash_3ch_regs), > + GFP_KERNEL); > + if (!regs) > + return -ENOMEM; > } else if (val == FLASH_SUBTYPE_4CH_VAL) { > flash_data->hw_type = QCOM_MVFLASH_4CH; > flash_data->max_channels = 4; > - regs = mvflash_4ch_regs; > + regs = devm_kmemdup(dev, mvflash_4ch_regs, sizeof(mvflash_3ch_regs), Minor: sizeof(mvflash_4ch_regs) > + GFP_KERNEL); > + if (!regs) > + return -ENOMEM; > > rc = regmap_read(regmap, reg_base + FLASH_REVISION_REG, &val); > if (rc < 0) { > @@ -880,6 +886,7 @@ static int qcom_flash_led_probe(struct platform_device *pdev) > dev_err(dev, "Failed to allocate regmap field, rc=%d\n", rc); > return rc; > } > + devm_kfree(dev, regs); /* devm_regmap_field_bulk_alloc() makes copies */ > > platform_set_drvdata(pdev, flash_data); > mutex_init(&flash_data->lock);
On 29/05/2025 05:11, Fenglin Wu wrote: >> -static struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = { >> +static const struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = { >> REG_FIELD(0x06, 0, 7), /* status1 */ >> REG_FIELD(0x07, 0, 6), /* status2 */ >> REG_FIELD(0x09, 0, 7), /* status3 */ >> @@ -854,11 +854,17 @@ static int qcom_flash_led_probe(struct platform_device *pdev) >> if (val == FLASH_SUBTYPE_3CH_PM8150_VAL || val == FLASH_SUBTYPE_3CH_PMI8998_VAL) { >> flash_data->hw_type = QCOM_MVFLASH_3CH; >> flash_data->max_channels = 3; >> - regs = mvflash_3ch_regs; >> + regs = devm_kmemdup(dev, mvflash_3ch_regs, sizeof(mvflash_3ch_regs), >> + GFP_KERNEL); >> + if (!regs) >> + return -ENOMEM; >> } else if (val == FLASH_SUBTYPE_4CH_VAL) { >> flash_data->hw_type = QCOM_MVFLASH_4CH; >> flash_data->max_channels = 4; >> - regs = mvflash_4ch_regs; >> + regs = devm_kmemdup(dev, mvflash_4ch_regs, sizeof(mvflash_3ch_regs), > > Minor: sizeof(mvflash_4ch_regs) Copy paste, thanks. > Best regards, Krzysztof
diff --git a/drivers/leds/flash/leds-qcom-flash.c b/drivers/leds/flash/leds-qcom-flash.c index b4c19be51c4d..b8a48c15d797 100644 --- a/drivers/leds/flash/leds-qcom-flash.c +++ b/drivers/leds/flash/leds-qcom-flash.c @@ -117,7 +117,7 @@ enum { REG_MAX_COUNT, }; -static struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = { +static const struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = { REG_FIELD(0x08, 0, 7), /* status1 */ REG_FIELD(0x09, 0, 7), /* status2 */ REG_FIELD(0x0a, 0, 7), /* status3 */ @@ -132,7 +132,7 @@ static struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = { REG_FIELD(0x58, 0, 2), /* therm_thrsh3 */ }; -static struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = { +static const struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = { REG_FIELD(0x06, 0, 7), /* status1 */ REG_FIELD(0x07, 0, 6), /* status2 */ REG_FIELD(0x09, 0, 7), /* status3 */ @@ -854,11 +854,17 @@ static int qcom_flash_led_probe(struct platform_device *pdev) if (val == FLASH_SUBTYPE_3CH_PM8150_VAL || val == FLASH_SUBTYPE_3CH_PMI8998_VAL) { flash_data->hw_type = QCOM_MVFLASH_3CH; flash_data->max_channels = 3; - regs = mvflash_3ch_regs; + regs = devm_kmemdup(dev, mvflash_3ch_regs, sizeof(mvflash_3ch_regs), + GFP_KERNEL); + if (!regs) + return -ENOMEM; } else if (val == FLASH_SUBTYPE_4CH_VAL) { flash_data->hw_type = QCOM_MVFLASH_4CH; flash_data->max_channels = 4; - regs = mvflash_4ch_regs; + regs = devm_kmemdup(dev, mvflash_4ch_regs, sizeof(mvflash_3ch_regs), + GFP_KERNEL); + if (!regs) + return -ENOMEM; rc = regmap_read(regmap, reg_base + FLASH_REVISION_REG, &val); if (rc < 0) { @@ -880,6 +886,7 @@ static int qcom_flash_led_probe(struct platform_device *pdev) dev_err(dev, "Failed to allocate regmap field, rc=%d\n", rc); return rc; } + devm_kfree(dev, regs); /* devm_regmap_field_bulk_alloc() makes copies */ platform_set_drvdata(pdev, flash_data); mutex_init(&flash_data->lock);
Driver in probe() updates each of 'reg_field' with 'reg_base': for (i = 0; i < REG_MAX_COUNT; i++) regs[i].reg += reg_base; 'reg_field' array (under variable 'regs' above) is statically allocated, this each re-bind would add another 'reg_base' leading to bogus register addresses. Constify the local 'reg_field' array and duplicate it in probe to solve this. Fixes: 96a2e242a5dc ("leds: flash: Add driver to support flash LED module in QCOM PMICs") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> --- This is a nice example why constifying static memory is useful. --- drivers/leds/flash/leds-qcom-flash.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)