I got the double free report:
BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390
CPU: 0 PID: 359 Comm: xrun Tainted: G W 5.15.0-rc3-00109-g4dfd49fafc4d-dirty #474 523b7f3c65c42247635e2ac04a95f61f9f36678d
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
dump_stack_lvl+0xe2/0x152
print_address_description.constprop.7+0x21/0x150
kasan_report_invalid_free+0x6f/0xa0
__kasan_slab_free+0x125/0x140
slab_free_freelist_hook+0x10d/0x240
kfree+0xce/0x390
iio_device_unregister_sysfs+0x108/0x13b [industrialio]
iio_dev_release+0x9e/0x10e [industrialio]
device_release+0xa5/0x240
kobject_put+0x1e5/0x540
put_device+0x20/0x30
devm_iio_device_release+0x21/0x30 [industrialio]
release_nodes+0xc3/0x3b0
devres_release_group+0x1da/0x2c0
i2c_device_probe+0x628/0xbb0
really_probe+0x285/0xc30
If __iio_device_register() fails, iio_dev_opaque->groups will be freed
in error path in iio_device_unregister_sysfs(), then iio_dev_release()
will call iio_device_unregister_sysfs() again, it causes double free.
Set iio_dev_opaque->groups to NULL when it's freed to fix this double free.
Fixes: 32f171724e5c ("iio: core: rework iio device group creation")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Reviewed-by: Alexandru Ardelean <ardeleanalex@xxxxxxxxx>
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
---
drivers/iio/industrialio-core.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 2dbb37e09b8c..2dc837db50f7 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1600,6 +1600,7 @@ static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
kfree(iio_dev_opaque->chan_attr_group.attrs);
iio_dev_opaque->chan_attr_group.attrs = NULL;
kfree(iio_dev_opaque->groups);
+ iio_dev_opaque->groups = NULL;
}
static void iio_dev_release(struct device *device)
--
2.25.1
