From: Yanfei Xu <yanfei.xu@xxxxxxxxxxxxx>
When using systemcall to read the rawdescriptors, make sure we won't
access to the rawdescriptors never allocated, which are number
exceed the USB_MAXCONFIG.
Reported-by: syzbot+256e56ddde8b8957eabd@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Yanfei Xu <yanfei.xu@xxxxxxxxxxxxx>
---
drivers/usb/core/sysfs.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index a2ca38e25e0c..1a7a625e5f55 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -895,7 +895,8 @@ read_descriptors(struct file *filp, struct kobject *kobj,
* configurations (config plus subsidiary descriptors).
*/
for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
- nleft > 0; ++cfgno) {
+ nleft > 0 &&
+ cfgno < USB_MAXCONFIG; ++cfgno) {
if (cfgno < 0) {
src = &udev->descriptor;
srclen = sizeof(struct usb_device_descriptor);
--
2.18.2
