| Message ID | 20211011092028.2310144-1-yangyingliang@huawei.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] iio: core: fix double free in iio_device_unregister_sysfs() | expand |
On Mon, Oct 11, 2021 at 12:12 PM Yang Yingliang <yangyingliang@huawei.com> wrote: > > 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 Please, reduce this noise to the ~4-5 important lines only!
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)
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@huawei.com> Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- drivers/iio/industrialio-core.c | 1 + 1 file changed, 1 insertion(+)