Bug 1283374
| Summary: | CVE-2016-2782 Local RedHat Enterprise Linux DoS – RHEL 7.1 Kernel crashes on invalid USB device descriptors (visor driver) [local-DoS] | ||||||||||
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| Product: | Red Hat Enterprise Linux 7 | Reporter: | Ralf Spenneberg <ralf> | ||||||||
| Component: | kernel | Assignee: | Don Zickus <dzickus> | ||||||||
| kernel sub component: | USB | QA Contact: | Mike Gahagan <mgahagan> | ||||||||
| Status: | CLOSED WONTFIX | Docs Contact: | |||||||||
| Severity: | high | ||||||||||
| Priority: | unspecified | CC: | sergej, vdronov | ||||||||
| Version: | 7.1 | Keywords: | Security, SecurityTracking | ||||||||
| Target Milestone: | rc | ||||||||||
| Target Release: | 7.3 | ||||||||||
| Hardware: | Unspecified | ||||||||||
| OS: | Unspecified | ||||||||||
| Whiteboard: | |||||||||||
| Fixed In Version: | Doc Type: | Release Note | |||||||||
| Doc Text: | Story Points: | --- | |||||||||
| Clone Of: | Environment: | ||||||||||
| Last Closed: | 2016-03-11 13:53:28 UTC | Type: | Bug | ||||||||
| Regression: | --- | Mount Type: | --- | ||||||||
| Documentation: | --- | CRM: | |||||||||
| Verified Versions: | Category: | --- | |||||||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||||||
| Embargoed: | |||||||||||
| Bug Depends On: | |||||||||||
| Bug Blocks: | 1312670 | ||||||||||
| Attachments: |
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Created attachment 1096281 [details]
vUSBf Payload
Created attachment 1096282 [details]
Stacktrace
Created attachment 1096284 [details]
Arduino firmware demonstrating the bug
this was fixed by Johan Hovold <johan> in the upstream commit cac9b50b0d75a1d50d6c056ff65c005f3224c8e0 by adding endpoints number check required: [ http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=cac9b50b0d75a1d50d6c056ff65c005f3224c8e0 ] + if (serial->num_bulk_in < 2 || serial->num_interrupt_in < 2) { + dev_err(&serial->interface->dev, "missing endpoints\n"); + return -ENODEV; + } Thank you for reporting this flaw. The Product Security has rated this flaw as having low security impact (bz#1312670), so the patch currently is not planned to be added to the RHEL source trees. The upstream and Fedora patches are completed (at least, I hope so), so the patch may get to the RHEL trees at the next USB subsystem code rebase. Public via: http://seclists.org/bugtraq/2016/Mar/86 |
Description of problem: Local RedHat Enterprise Linux DoS – RHEL 7.1 Kernel crashes on invalid USB device descriptors (visor driver) [local-DoS] Version-Release number of selected component (if applicable): Kernel-Version: 3.10.0-229.20.1.el7.x86_64 How reproducible: always OpenSource Security Ralf Spenneberg Am Bahnhof 3-5 48565 Steinfurt info Date: November 12th, 2015 Authors: Sergej Schumilo, Hendrik Schwartke, Ralf Spenneberg CVE: not yet assigned CVSS: 4.9 (AV:L/AC:L/Au:N/C:N/I:N/A:C) Title: Local RedHat Enterprise Linux DoS – RHEL 7.1 Kernel crashes on invalid USB device descriptors (visor driver) [local-DoS] Severity: Critical. The Kernel panics. A reboot is required. Ease of Exploitation: Trivial Vulnerability type: Wrong input validation Products: RHEL 7.1 including all updates Kernel-Version: 3.10.0-229.20.1.el7.x86_64 (for debugging-purposes we used the CentOS Kernel kernel-debuginfo-3.10.0-229.14.1.el7) Abstract The Kernel 3.10.0-229.20.1.el7.x86_64 crashes when presented a buggy USB device which requires the visor driver. Detailed product description We confirmed the bug on the following system: RHEL 7.1 Kernel = 3.10.0-229.20.1.el7.x86_64 Further products or kernel versions have not been tested. How reproducible: Always Actual results: Kernel crashes Description: The bug was found using the USB-fuzzing framework vUSBf from Sergej Schumilo (github.com/schumilo) using the following device descriptor: ######### PAYLOAD 1 ######### [*] Device-Descriptor bLength: 0x12 bDescriptorType: 0x1 bcdUSB: 0x200 bDeviceClass: 0x3 bDeviceSubClass: 0x0 bDeviceProtocol: 0x0 bMaxPacketSize: 0x40 idVendor: 0x82d idProduct: 0x200 bcdDevice: 0x100 iManufacturer: 0x1 iProduct: 0x2 iSerialNumbers: 0x3 bNumConfigurations: 0x1 The treo_attach function does not use the num_ports (struct usb_serial) value for any kind of sanity checks during the initialization process. Due to an incomplete sanity check, the driver could try to dereference a null-pointer if a malformed device-descriptor is presented (zero-value for bNumEndpoints or no required endpoint-descriptors is provided). This results in a crash of the system. **** $ nm visor.ko.debug | grep treo_attach 00000000000005f0 t treo_attach $ addr2line -e visor.ko.debug 0x651 /usr/src/debug/kernel-3.10.0-229.14.1.el7/linux-3.10.0-229.14.1.el7.x86_64/drivers/usb/serial/visor.c:577 **** **** CentOS-Kernel linux-3.10.0-229.14.1.el7 (drivers/usb/serial/visor.c) ... 554 #define COPY_PORT(dest, src) \ 555 do { \ 556 int i; \ 557 \ 558 for (i = 0; i < ARRAY_SIZE(src->read_urbs); ++i) { \ 559 dest->read_urbs[i] = src->read_urbs[i]; \ /* Possible Nullpointer-Dereference */ 560 dest->read_urbs[i]->context = dest; \ 561 dest->bulk_in_buffers[i] = src->bulk_in_buffers[i]; \ 562 } \ 563 dest->read_urb = src->read_urb; \ 564 dest->bulk_in_endpointAddress = src->bulk_in_endpointAddress;\ 565 dest->bulk_in_buffer = src->bulk_in_buffer; \ 566 dest->bulk_in_size = src->bulk_in_size; \ 567 dest->interrupt_in_urb = src->interrupt_in_urb; \ 568 dest->interrupt_in_urb->context = dest; \ 569 dest->interrupt_in_endpointAddress = \ 570 src->interrupt_in_endpointAddress;\ 571 dest->interrupt_in_buffer = src->interrupt_in_buffer; \ 572 } while (0); 573 574 swap_port = kmalloc(sizeof(*swap_port), GFP_KERNEL); 575 if (!swap_port) 576 return -ENOMEM; 577 COPY_PORT(swap_port, serial->port[0]); /* no sanity-check! */ 578 COPY_PORT(serial->port[0], serial->port[1]); /* no sanity-check! */ 579 COPY_PORT(serial->port[1], swap_port); /* no sanity-check! */ ... **** [*] Configuration-Descriptor bLength: 0x9 bDescriptorType: 0x2 wTotalLength: 0x27 bNumInterfaces: 0x1 bConfigurationValue: 0x1 iConfiguration: 0x0 bmAttributes: 0x0 bMaxPower: 0x31 [*] Interface-Descriptor bLength: 0x9 bDescriptorType: 0x4 bInterfaceNumber: 0x0 bAlternateSetting: 0x0 bNumEndpoints: 0x3 bInterfaceClass: 0x0 bInterfaceSubClass: 0x0 bInterfaceProtocol: 0x0 [*] Endpoint-Descriptor bLength: 0x7 bDescriptorType: 0x5 bEndpointAddress: 0x81 bmAttribut: 0x3 wMaxPacketSize: 0x404 bInterval: 0xc [*] Endpoint-Descriptor bLength: 0x7 bDescriptorType: 0x5 bEndpointAddress: 0x1 bmAttribut: 0x2 wMaxPacketSize: 0x4 bInterval: 0xc [*] Endpoint-Descriptor bLength: 0x7 bDescriptorType: 0x5 bEndpointAddress: 0x82 bmAttribut: 0x1 wMaxPacketSize: 0x4 bInterval: 0xc Proof of Concept: 1) The bug can be reproduced using USB-fuzzing framework vUSBf from Sergej Schumilo (github.com/schumilo). The attached vUSBf-obj file contains the payload. Please let us know if you would like to use the Facedancer board. In such case, we could also provide a patched version of vUSBf which allows to reproduce vUSBf-Payloads using the Facedancer board. 2) For a proof of concept we are providing also an Arduino firmware file. Just flash it on Arduino Leonardo and plug it into any RHEL machine. The Arduino will emulate the defective USB device. avrdude -v -p ATMEGA32u4 -c avr109 -P /dev/ttyACM0 -b 57600 -U flash:w:binary.hex The file binary.hex has been attached to this bug report. To prevent automated sending of payloads, use a jumper to connect port D3 and 5V! Severity and Ease of Exploitation The security weakness can be easily exploited. Using our Arduino firmware only physical access to the system is required. Additional info: Stacktrace, vUSBf-Payload, Arduino-Firmware attached. Please assign a CVE for this issue since this is a local DoS of the targeted system. CVSS 4.9 (AV:L/AC:L/Au:N/C:N/I:N/A:C)