This commit fixes the following oops: [10238.622067] scsi host3: uas_eh_bus_reset_handler start [10240.766164] usb 3-4: reset SuperSpeed USB device number 3 using xhci_hcd [10245.779365] usb 3-4: device descriptor read/8, error -110 [10245.883331] usb 3-4: reset SuperSpeed USB device number 3 using xhci_hcd [10250.897603] usb 3-4: device descriptor read/8, error -110 [10251.058200] BUG: unable to handle kernel NULL pointer dereference at 0000000000000040 [10251.058244] IP: [<ffffffff815ac6e1>] xhci_check_streams_endpoint+0x91/0x140 <snip> [10251.059473] Call Trace: [10251.059487] [<ffffffff815aca6c>] xhci_calculate_streams_and_bitmask+0xbc/0x130 [10251.059520] [<ffffffff815aeb5f>] xhci_alloc_streams+0x10f/0x5a0 [10251.059548] [<ffffffff810a4685>] ? check_preempt_curr+0x75/0xa0 [10251.059575] [<ffffffff810a46dc>] ? ttwu_do_wakeup+0x2c/0x100 [10251.059601] [<ffffffff810a49e6>] ? ttwu_do_activate.constprop.111+0x66/0x70 [10251.059635] [<ffffffff815779ab>] usb_alloc_streams+0xab/0xf0 [10251.059662] [<ffffffffc0616b48>] uas_configure_endpoints+0x128/0x150 [uas] [10251.059694] [<ffffffffc0616bac>] uas_post_reset+0x3c/0xb0 [uas] [10251.059722] [<ffffffff815727d9>] usb_reset_device+0x1b9/0x2a0 [10251.059749] [<ffffffffc0616f42>] uas_eh_bus_reset_handler+0xb2/0x190 [uas] [10251.059781] [<ffffffff81514293>] scsi_try_bus_reset+0x53/0x110 [10251.059808] [<ffffffff815163b7>] scsi_eh_bus_reset+0xf7/0x270 <snip> The problem is the following call sequence (simplified): 1) usb_reset_device 2) usb_reset_and_verify_device 2) hub_port_init 3) hub_port_finish_reset 3) xhci_discover_or_reset_device This frees xhci->devs[slot_id]->eps[ep_index].ring for all eps but 0 4) usb_get_device_descriptor This fails 5) hub_port_init fails 6) usb_reset_and_verify_device fails, does not restore device config 7) uas_post_reset 8) xhci_alloc_streams NULL deref on the free-ed ring This commit fixes this by not allowing usb_alloc_streams to continue if the device is not configured. Note that we do allow usb_free_streams to continue after a (logical) disconnect, as it is necessary to explicitly free the streams at the xhci controller level. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/usb/core/hcd.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 487abcf..258e6fe 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2057,6 +2057,8 @@ int usb_alloc_streams(struct usb_interface *interface, return -EINVAL; if (dev->speed != USB_SPEED_SUPER) return -EINVAL; + if (dev->state < USB_STATE_CONFIGURED) + return -ENODEV; for (i = 0; i < num_eps; i++) { /* Streams only apply to bulk endpoints. */ -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html