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authorAlan Stern <stern@rowland.harvard.edu>2025-01-22 14:26:17 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2025-02-03 16:41:48 +0100
commit2240fed37afbcdb5e8b627bc7ad986891100e05d (patch)
tree125006d91eeb824e7c3838c6256906a9a201bf87 /drivers/usb/core
parent335a1fc1193481f8027f176649c72868172f6f8b (diff)
USB: hub: Ignore non-compliant devices with too many configs or interfaces
Robert Morris created a test program which can cause usb_hub_to_struct_hub() to dereference a NULL or inappropriate pointer: Oops: general protection fault, probably for non-canonical address 0xcccccccccccccccc: 0000 [#1] SMP DEBUG_PAGEALLOC PTI CPU: 7 UID: 0 PID: 117 Comm: kworker/7:1 Not tainted 6.13.0-rc3-00017-gf44d154d6e3d #14 Hardware name: FreeBSD BHYVE/BHYVE, BIOS 14.0 10/17/2021 Workqueue: usb_hub_wq hub_event RIP: 0010:usb_hub_adjust_deviceremovable+0x78/0x110 ... Call Trace: <TASK> ? die_addr+0x31/0x80 ? exc_general_protection+0x1b4/0x3c0 ? asm_exc_general_protection+0x26/0x30 ? usb_hub_adjust_deviceremovable+0x78/0x110 hub_probe+0x7c7/0xab0 usb_probe_interface+0x14b/0x350 really_probe+0xd0/0x2d0 ? __pfx___device_attach_driver+0x10/0x10 __driver_probe_device+0x6e/0x110 driver_probe_device+0x1a/0x90 __device_attach_driver+0x7e/0xc0 bus_for_each_drv+0x7f/0xd0 __device_attach+0xaa/0x1a0 bus_probe_device+0x8b/0xa0 device_add+0x62e/0x810 usb_set_configuration+0x65d/0x990 usb_generic_driver_probe+0x4b/0x70 usb_probe_device+0x36/0xd0 The cause of this error is that the device has two interfaces, and the hub driver binds to interface 1 instead of interface 0, which is where usb_hub_to_struct_hub() looks. We can prevent the problem from occurring by refusing to accept hub devices that violate the USB spec by having more than one configuration or interface. Reported-and-tested-by: Robert Morris <rtm@csail.mit.edu> Cc: stable <stable@kernel.org> Closes: https://lore.kernel.org/linux-usb/95564.1737394039@localhost/ Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Link: https://lore.kernel.org/r/c27f3bf4-63d8-4fb5-ac82-09e3cd19f61c@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/core')
-rw-r--r--drivers/usb/core/hub.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index c3f839637cb5..0cd44f1fd56d 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1849,6 +1849,17 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
hdev = interface_to_usbdev(intf);
/*
+ * The USB 2.0 spec prohibits hubs from having more than one
+ * configuration or interface, and we rely on this prohibition.
+ * Refuse to accept a device that violates it.
+ */
+ if (hdev->descriptor.bNumConfigurations > 1 ||
+ hdev->actconfig->desc.bNumInterfaces > 1) {
+ dev_err(&intf->dev, "Invalid hub with more than one config or interface\n");
+ return -EINVAL;
+ }
+
+ /*
* Set default autosuspend delay as 0 to speedup bus suspend,
* based on the below considerations:
*