| Message ID | 1542818142-27800-1-git-send-email-hofrat@osadl.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | gpio: mt7621: handle failure of devm_kasprintf() | expand |
śr., 21 lis 2018 o 17:39 Nicholas Mc Guire <hofrat@osadl.org> napisał(a): > > kasprintf() may return NULL on failure of internal allocation thus the > assigned label is not safe if not explicitly checked. On error > mediatek_gpio_bank_probe() returns negative values so -ENOMEM in the > (unlikely) failure case should be fine here. > > Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> > Fixes: 4ba9c3afda41 ("gpio: mt7621: Add a driver for MT7621") > --- > > Problem located with experimental coccinelle script > > Patch was compile tested with: omega2p_defconfig, SOC_MT7621=y, > GPIOLIB=y, GPIO_MT7621=y > > Patch is against 4.20-rc3 (localversion-next is next-20181121) > > drivers/gpio/gpio-mt7621.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpio/gpio-mt7621.c b/drivers/gpio/gpio-mt7621.c > index d72af6f..42f0c67 100644 > --- a/drivers/gpio/gpio-mt7621.c > +++ b/drivers/gpio/gpio-mt7621.c > @@ -244,6 +244,10 @@ mediatek_gpio_bank_probe(struct device *dev, > rg->chip.of_xlate = mediatek_gpio_xlate; > rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d", > dev_name(dev), bank); > + if (!rg->chip.label) { > + dev_err(dev, "Could not allocate label\n"); No need for an error message here, an -ENOMEM says enough. Bart > + return -ENOMEM; > + } > > ret = devm_gpiochip_add_data(dev, &rg->chip, mtk); > if (ret < 0) { > -- > 2.1.4 >
On Wed, Nov 21, 2018 at 05:43:43PM +0100, Bartosz Golaszewski wrote: > ??r., 21 lis 2018 o 17:39 Nicholas Mc Guire <hofrat@osadl.org> napisa??(a): > > > > kasprintf() may return NULL on failure of internal allocation thus the > > assigned label is not safe if not explicitly checked. On error > > mediatek_gpio_bank_probe() returns negative values so -ENOMEM in the > > (unlikely) failure case should be fine here. > > > > Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> > > Fixes: 4ba9c3afda41 ("gpio: mt7621: Add a driver for MT7621") > > --- > > > > Problem located with experimental coccinelle script > > > > Patch was compile tested with: omega2p_defconfig, SOC_MT7621=y, > > GPIOLIB=y, GPIO_MT7621=y > > > > Patch is against 4.20-rc3 (localversion-next is next-20181121) > > > > drivers/gpio/gpio-mt7621.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/gpio/gpio-mt7621.c b/drivers/gpio/gpio-mt7621.c > > index d72af6f..42f0c67 100644 > > --- a/drivers/gpio/gpio-mt7621.c > > +++ b/drivers/gpio/gpio-mt7621.c > > @@ -244,6 +244,10 @@ mediatek_gpio_bank_probe(struct device *dev, > > rg->chip.of_xlate = mediatek_gpio_xlate; > > rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d", > > dev_name(dev), bank); > > + if (!rg->chip.label) { > > + dev_err(dev, "Could not allocate label\n"); > > No need for an error message here, an -ENOMEM says enough. > I just thought its more consistent with the rest of the code - and as it is a highly unlikely event it would probably be hard to pinpoint as some of the other functions can return -ENOMEM (but with a message). ....and the call site of mediatek_gpio_bank_probe() actually currently ignores the return value so the -ENOMEM would go unnoticed which is a bug as well - patch for that a bit later. anyway fine with me - I´ll send a V2 and drop the dev_err() here. thx! hofrat > Bart > > > + return -ENOMEM; > > + } > > > > ret = devm_gpiochip_add_data(dev, &rg->chip, mtk); > > if (ret < 0) { > > -- > > 2.1.4 > >
diff --git a/drivers/gpio/gpio-mt7621.c b/drivers/gpio/gpio-mt7621.c index d72af6f..42f0c67 100644 --- a/drivers/gpio/gpio-mt7621.c +++ b/drivers/gpio/gpio-mt7621.c @@ -244,6 +244,10 @@ mediatek_gpio_bank_probe(struct device *dev, rg->chip.of_xlate = mediatek_gpio_xlate; rg->chip.label = devm_kasprintf(dev, GFP_KERNEL, "%s-bank%d", dev_name(dev), bank); + if (!rg->chip.label) { + dev_err(dev, "Could not allocate label\n"); + return -ENOMEM; + } ret = devm_gpiochip_add_data(dev, &rg->chip, mtk); if (ret < 0) {
kasprintf() may return NULL on failure of internal allocation thus the assigned label is not safe if not explicitly checked. On error mediatek_gpio_bank_probe() returns negative values so -ENOMEM in the (unlikely) failure case should be fine here. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Fixes: 4ba9c3afda41 ("gpio: mt7621: Add a driver for MT7621") --- Problem located with experimental coccinelle script Patch was compile tested with: omega2p_defconfig, SOC_MT7621=y, GPIOLIB=y, GPIO_MT7621=y Patch is against 4.20-rc3 (localversion-next is next-20181121) drivers/gpio/gpio-mt7621.c | 4 ++++ 1 file changed, 4 insertions(+)