On Sun, Nov 17, 2024 at 03:33:28PM +0800, Markus Rechberger wrote: > Hi, > > > the issue was first reported at vdr-portal.de > https://www-vdr--portal-de.translate.goog/forum/index.php?thread/136541-empfehlung-dvb-s2-tuner-oder-satip/&postID=1376196&_x_tr_sl=de&_x_tr_tl=en&_x_tr_hl=de&_x_tr_pto=wapp#post1376196 > > we've got around a highly critical bug in the xhci driver. > > https://sundtek.de/support/uxvd32.txt > > In xhci.c > > The bug is still active in Mainline: > https://github.com/torvalds/linux/blob/master/drivers/usb/host/xhci.c#L2382 > > static int xhci_check_bw_table(struct xhci_hcd *xhci, > struct xhci_virt_device *virt_dev, > int old_active_eps) > > bw_table can end up with a NULL pointer. > > This problem will lead to a complete kernel crash, rendering the entire > system unusable without any access to the actual linux system. > > How to trigger the problem? > Short D+/D- or pull them to ground on a USB device while connecting the > device. > > The problem can happen due to following cases: > * a device is getting suddenly disconnected during enumeration > * a faulty cable > * a faulty device > * a malicious device triggers this issue on purpose > * if there are electrical issues during connecting a device. Bad hardware is always a problem, can you send a patch to resolve this as you seem to be able to reproduce it? thanks, greg k-h
