This is a note to let you know that I've just added the patch titled iio: core: check return value when calling dev_set_name() to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-testing branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will be merged to the char-misc-next branch sometime soon, after it passes testing, and the merge window is open. If you have any questions about this process, please let me know. >From fe6f45f6ba22d625a8500cbad0237c60dd3117ee Mon Sep 17 00:00:00 2001 From: Yang Yingliang <yangyingliang@xxxxxxxxxx> Date: Tue, 12 Oct 2021 14:36:24 +0800 Subject: iio: core: check return value when calling dev_set_name() I got a null-ptr-deref report when doing fault injection test: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:strlen+0x0/0x20 Call Trace: start_creating+0x199/0x2f0 debugfs_create_dir+0x25/0x430 __iio_device_register+0x4da/0x1b40 [industrialio] __devm_iio_device_register+0x22/0x80 [industrialio] max1027_probe+0x639/0x860 [max1027] spi_probe+0x183/0x210 really_probe+0x285/0xc30 If dev_set_name() fails, the dev_name() is null, check the return value of dev_set_name() to avoid the null-ptr-deref. Reported-by: Hulk Robot <hulkci@xxxxxxxxxx> Fixes: e553f182d55b ("staging: iio: core: Introduce debugfs support...") Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx> Cc: <Stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20211012063624.3167460-1-yangyingliang@xxxxxxxxxx Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> --- drivers/iio/industrialio-core.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 2dbb37e09b8c..48fda6a79076 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -1664,7 +1664,13 @@ struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv) kfree(iio_dev_opaque); return NULL; } - dev_set_name(&indio_dev->dev, "iio:device%d", iio_dev_opaque->id); + + if (dev_set_name(&indio_dev->dev, "iio:device%d", iio_dev_opaque->id)) { + ida_simple_remove(&iio_ida, iio_dev_opaque->id); + kfree(iio_dev_opaque); + return NULL; + } + INIT_LIST_HEAD(&iio_dev_opaque->buffer_list); INIT_LIST_HEAD(&iio_dev_opaque->ioctl_handlers); -- 2.33.1