[PATCH] usb: core: add bos NULL pointer checking condition

[Woo-kwang Lee]

This issue occurs when connecting Galaxy S22 and abnormal SEC Dex Adapter.
When the abnormal adapter is connected, kernel panic always occurs after a
few seconds.
This occurs due to unable to get BOS descriptor, usb_release_bos_descriptor
set dev->bos = NULL.

- usb_reset_and_verify_device
  - hub_port_init
  - usb_release_bos_descriptor
    - dev->bos = NULL;

hub_port_connect_change() calls portspeed(), and portspeed() calls hub_is_s
uperspeedplus().
Finally, hub_is_superspeedplus() calls hdev->bos->ssp_cap.
It needs to check hdev->bos is NULL to prevent a kernel panic.

usb 3-1: new SuperSpeed Gen 1 USB device number 16 using xhci-hcd-exynos
usb 3-1: unable to get BOS descriptor set
usb 3-1: Product: USB3.0 Hub
Unable to handle kernel NULL pointer dereference at virtual address 0000018

Call trace:
 hub_port_connect_change+0x8c/0x538
 port_event+0x244/0x764
 hub_event+0x158/0x474
 process_one_work+0x204/0x550
 worker_thread+0x28c/0x580
 kthread+0x13c/0x178
 ret_from_fork+0x10/0x30

- hub_port_connect_change
  - portspeed
    - hub_is_superspeedplus

Fixes: 0cdd49a1d1a4 ("usb: Support USB 3.1 extended port status request")
Signed-off-by: Woo-kwang Lee <wookwang.lee@xxxxxxxxxxx>
---
 drivers/usb/core/hub.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 73f4482d833a..cc0c994e19e5 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -139,6 +139,8 @@ static inline int hub_is_superspeed(struct usb_device *hdev)
 
 static inline int hub_is_superspeedplus(struct usb_device *hdev)
 {
+	if (!hdev->bos)
+		return 0;
 	return (hdev->descriptor.bDeviceProtocol == USB_HUB_PR_SS &&
 		le16_to_cpu(hdev->descriptor.bcdUSB) >= 0x0310 &&
 		hdev->bos->ssp_cap);
-- 
2.17.1