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@huawei.com 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@huawei.com Fixes: e553f182d55b ("staging: iio: core: Introduce debugfs support...") Signed-off-by: Yang Yingliang yangyingliang@huawei.com Cc: Stable@vger.kernel.org Link: https://lore.kernel.org/r/20211012063624.3167460-1-yangyingliang@huawei.com Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- 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);