diff options
| author | Jiantao Zhang <water.zhangjiantao@huawei.com> | 2022-11-21 13:08:05 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-11-22 17:31:20 +0100 |
| commit | afdc12887f2b2ecf20d065a7d81ad29824155083 (patch) | |
| tree | ef67653c3fda7f9c7c586f8e33d5bacf1095164e /drivers/usb/gadget/udc/core.c | |
| parent | 581c848b610dbf3fe1ed4d85fd53d0743c61faba (diff) | |
| download | linux-afdc12887f2b2ecf20d065a7d81ad29824155083.tar.bz2 | |
USB: gadget: Fix use-after-free during usb config switch
In the process of switching USB config from rndis to other config,
if the hardware does not support the ->pullup callback, or the
hardware encounters a low probability fault, both of them may cause
the ->pullup callback to fail, which will then cause a system panic
(use after free).
The gadget drivers sometimes need to be unloaded regardless of the
hardware's behavior.
Analysis as follows:
=======================================================================
(1) write /config/usb_gadget/g1/UDC "none"
gether_disconnect+0x2c/0x1f8
rndis_disable+0x4c/0x74
composite_disconnect+0x74/0xb0
configfs_composite_disconnect+0x60/0x7c
usb_gadget_disconnect+0x70/0x124
usb_gadget_unregister_driver+0xc8/0x1d8
gadget_dev_desc_UDC_store+0xec/0x1e4
(2) rm /config/usb_gadget/g1/configs/b.1/f1
rndis_deregister+0x28/0x54
rndis_free+0x44/0x7c
usb_put_function+0x14/0x1c
config_usb_cfg_unlink+0xc4/0xe0
configfs_unlink+0x124/0x1c8
vfs_unlink+0x114/0x1dc
(3) rmdir /config/usb_gadget/g1/functions/rndis.gs4
panic+0x1fc/0x3d0
do_page_fault+0xa8/0x46c
do_mem_abort+0x3c/0xac
el1_sync_handler+0x40/0x78
0xffffff801138f880
rndis_close+0x28/0x34
eth_stop+0x74/0x110
dev_close_many+0x48/0x194
rollback_registered_many+0x118/0x814
unregister_netdev+0x20/0x30
gether_cleanup+0x1c/0x38
rndis_attr_release+0xc/0x14
kref_put+0x74/0xb8
configfs_rmdir+0x314/0x374
If gadget->ops->pullup() return an error, function rndis_close() will be
called, then it will causes a use-after-free problem.
=======================================================================
Fixes: 0a55187a1ec8 ("USB: gadget core: Issue ->disconnect() callback from usb_gadget_disconnect()")
Signed-off-by: Jiantao Zhang <water.zhangjiantao@huawei.com>
Signed-off-by: TaoXue <xuetao09@huawei.com>
Link: https://lore.kernel.org/r/20221121130805.10735-1-water.zhangjiantao@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/gadget/udc/core.c')
| -rw-r--r-- | drivers/usb/gadget/udc/core.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index c63c0c2cf649..bf9878e1a72a 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -734,13 +734,13 @@ int usb_gadget_disconnect(struct usb_gadget *gadget) } ret = gadget->ops->pullup(gadget, 0); - if (!ret) { + if (!ret) gadget->connected = 0; - mutex_lock(&udc_lock); - if (gadget->udc->driver) - gadget->udc->driver->disconnect(gadget); - mutex_unlock(&udc_lock); - } + + mutex_lock(&udc_lock); + if (gadget->udc->driver) + gadget->udc->driver->disconnect(gadget); + mutex_unlock(&udc_lock); out: trace_usb_gadget_disconnect(gadget, ret); |