linux-stable/drivers/usb/usbip/usbip_common.h
Malte Leip c409ca3be3 usb: usbip: fix isoc packet num validation in get_pipe
Change the validation of number_of_packets in get_pipe to compare the
number of packets to a fixed maximum number of packets allowed, set to
be 1024. This number was chosen due to it being used by other drivers as
well, for example drivers/usb/host/uhci-q.c

Background/reason:
The get_pipe function in stub_rx.c validates the number of packets in
isochronous mode and aborts with an error if that number is too large,
in order to prevent malicious input from possibly triggering large
memory allocations. This was previously done by checking whether
pdu->u.cmd_submit.number_of_packets is bigger than the number of packets
that would be needed for pdu->u.cmd_submit.transfer_buffer_length bytes
if all except possibly the last packet had maximum length, given by
usb_endpoint_maxp(epd) *  usb_endpoint_maxp_mult(epd). This leads to an
error if URBs with packets shorter than the maximum possible length are
submitted, which is allowed according to
Documentation/driver-api/usb/URB.rst and occurs for example with the
snd-usb-audio driver.

Fixes: c6688ef9f2 ("usbip: fix stub_rx: harden CMD_SUBMIT path to handle malicious input")
Signed-off-by: Malte Leip <malte@leip.net>
Cc: stable <stable@vger.kernel.org>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:11:41 +02:00

340 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2003-2008 Takahiro Hirofuchi
* Copyright (C) 2015-2016 Samsung Electronics
* Krzysztof Opasiak <k.opasiak@samsung.com>
*/
#ifndef __USBIP_COMMON_H
#define __USBIP_COMMON_H
#include <linux/compiler.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/net.h>
#include <linux/printk.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/usb.h>
#include <linux/wait.h>
#include <linux/sched/task.h>
#include <uapi/linux/usbip.h>
#undef pr_fmt
#ifdef DEBUG
#define pr_fmt(fmt) KBUILD_MODNAME ": %s:%d: " fmt, __func__, __LINE__
#else
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#endif
enum {
usbip_debug_xmit = (1 << 0),
usbip_debug_sysfs = (1 << 1),
usbip_debug_urb = (1 << 2),
usbip_debug_eh = (1 << 3),
usbip_debug_stub_cmp = (1 << 8),
usbip_debug_stub_dev = (1 << 9),
usbip_debug_stub_rx = (1 << 10),
usbip_debug_stub_tx = (1 << 11),
usbip_debug_vhci_rh = (1 << 8),
usbip_debug_vhci_hc = (1 << 9),
usbip_debug_vhci_rx = (1 << 10),
usbip_debug_vhci_tx = (1 << 11),
usbip_debug_vhci_sysfs = (1 << 12)
};
#define usbip_dbg_flag_xmit (usbip_debug_flag & usbip_debug_xmit)
#define usbip_dbg_flag_vhci_rh (usbip_debug_flag & usbip_debug_vhci_rh)
#define usbip_dbg_flag_vhci_hc (usbip_debug_flag & usbip_debug_vhci_hc)
#define usbip_dbg_flag_vhci_rx (usbip_debug_flag & usbip_debug_vhci_rx)
#define usbip_dbg_flag_vhci_tx (usbip_debug_flag & usbip_debug_vhci_tx)
#define usbip_dbg_flag_stub_rx (usbip_debug_flag & usbip_debug_stub_rx)
#define usbip_dbg_flag_stub_tx (usbip_debug_flag & usbip_debug_stub_tx)
#define usbip_dbg_flag_vhci_sysfs (usbip_debug_flag & usbip_debug_vhci_sysfs)
extern unsigned long usbip_debug_flag;
extern struct device_attribute dev_attr_usbip_debug;
#define usbip_dbg_with_flag(flag, fmt, args...) \
do { \
if (flag & usbip_debug_flag) \
pr_debug(fmt, ##args); \
} while (0)
#define usbip_dbg_sysfs(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_sysfs, fmt , ##args)
#define usbip_dbg_xmit(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_xmit, fmt , ##args)
#define usbip_dbg_urb(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_urb, fmt , ##args)
#define usbip_dbg_eh(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_eh, fmt , ##args)
#define usbip_dbg_vhci_rh(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_vhci_rh, fmt , ##args)
#define usbip_dbg_vhci_hc(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_vhci_hc, fmt , ##args)
#define usbip_dbg_vhci_rx(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_vhci_rx, fmt , ##args)
#define usbip_dbg_vhci_tx(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_vhci_tx, fmt , ##args)
#define usbip_dbg_vhci_sysfs(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_vhci_sysfs, fmt , ##args)
#define usbip_dbg_stub_cmp(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_stub_cmp, fmt , ##args)
#define usbip_dbg_stub_rx(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_stub_rx, fmt , ##args)
#define usbip_dbg_stub_tx(fmt, args...) \
usbip_dbg_with_flag(usbip_debug_stub_tx, fmt , ##args)
/*
* USB/IP request headers
*
* Each request is transferred across the network to its counterpart, which
* facilitates the normal USB communication. The values contained in the headers
* are basically the same as in a URB. Currently, four request types are
* defined:
*
* - USBIP_CMD_SUBMIT: a USB request block, corresponds to usb_submit_urb()
* (client to server)
*
* - USBIP_RET_SUBMIT: the result of USBIP_CMD_SUBMIT
* (server to client)
*
* - USBIP_CMD_UNLINK: an unlink request of a pending USBIP_CMD_SUBMIT,
* corresponds to usb_unlink_urb()
* (client to server)
*
* - USBIP_RET_UNLINK: the result of USBIP_CMD_UNLINK
* (server to client)
*
*/
#define USBIP_CMD_SUBMIT 0x0001
#define USBIP_CMD_UNLINK 0x0002
#define USBIP_RET_SUBMIT 0x0003
#define USBIP_RET_UNLINK 0x0004
#define USBIP_DIR_OUT 0x00
#define USBIP_DIR_IN 0x01
/*
* Arbitrary limit for the maximum number of isochronous packets in an URB,
* compare for example the uhci_submit_isochronous function in
* drivers/usb/host/uhci-q.c
*/
#define USBIP_MAX_ISO_PACKETS 1024
/**
* struct usbip_header_basic - data pertinent to every request
* @command: the usbip request type
* @seqnum: sequential number that identifies requests; incremented per
* connection
* @devid: specifies a remote USB device uniquely instead of busnum and devnum;
* in the stub driver, this value is ((busnum << 16) | devnum)
* @direction: direction of the transfer
* @ep: endpoint number
*/
struct usbip_header_basic {
__u32 command;
__u32 seqnum;
__u32 devid;
__u32 direction;
__u32 ep;
} __packed;
/**
* struct usbip_header_cmd_submit - USBIP_CMD_SUBMIT packet header
* @transfer_flags: URB flags
* @transfer_buffer_length: the data size for (in) or (out) transfer
* @start_frame: initial frame for isochronous or interrupt transfers
* @number_of_packets: number of isochronous packets
* @interval: maximum time for the request on the server-side host controller
* @setup: setup data for a control request
*/
struct usbip_header_cmd_submit {
__u32 transfer_flags;
__s32 transfer_buffer_length;
/* it is difficult for usbip to sync frames (reserved only?) */
__s32 start_frame;
__s32 number_of_packets;
__s32 interval;
unsigned char setup[8];
} __packed;
/**
* struct usbip_header_ret_submit - USBIP_RET_SUBMIT packet header
* @status: return status of a non-iso request
* @actual_length: number of bytes transferred
* @start_frame: initial frame for isochronous or interrupt transfers
* @number_of_packets: number of isochronous packets
* @error_count: number of errors for isochronous transfers
*/
struct usbip_header_ret_submit {
__s32 status;
__s32 actual_length;
__s32 start_frame;
__s32 number_of_packets;
__s32 error_count;
} __packed;
/**
* struct usbip_header_cmd_unlink - USBIP_CMD_UNLINK packet header
* @seqnum: the URB seqnum to unlink
*/
struct usbip_header_cmd_unlink {
__u32 seqnum;
} __packed;
/**
* struct usbip_header_ret_unlink - USBIP_RET_UNLINK packet header
* @status: return status of the request
*/
struct usbip_header_ret_unlink {
__s32 status;
} __packed;
/**
* struct usbip_header - common header for all usbip packets
* @base: the basic header
* @u: packet type dependent header
*/
struct usbip_header {
struct usbip_header_basic base;
union {
struct usbip_header_cmd_submit cmd_submit;
struct usbip_header_ret_submit ret_submit;
struct usbip_header_cmd_unlink cmd_unlink;
struct usbip_header_ret_unlink ret_unlink;
} u;
} __packed;
/*
* This is the same as usb_iso_packet_descriptor but packed for pdu.
*/
struct usbip_iso_packet_descriptor {
__u32 offset;
__u32 length; /* expected length */
__u32 actual_length;
__u32 status;
} __packed;
enum usbip_side {
USBIP_VHCI,
USBIP_STUB,
USBIP_VUDC,
};
/* event handler */
#define USBIP_EH_SHUTDOWN (1 << 0)
#define USBIP_EH_BYE (1 << 1)
#define USBIP_EH_RESET (1 << 2)
#define USBIP_EH_UNUSABLE (1 << 3)
#define SDEV_EVENT_REMOVED (USBIP_EH_SHUTDOWN | USBIP_EH_BYE)
#define SDEV_EVENT_DOWN (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
#define SDEV_EVENT_ERROR_TCP (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
#define SDEV_EVENT_ERROR_SUBMIT (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
#define SDEV_EVENT_ERROR_MALLOC (USBIP_EH_SHUTDOWN | USBIP_EH_UNUSABLE)
#define VUDC_EVENT_REMOVED (USBIP_EH_SHUTDOWN | USBIP_EH_RESET | USBIP_EH_BYE)
#define VUDC_EVENT_DOWN (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
#define VUDC_EVENT_ERROR_TCP (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
/* catastrophic emulated usb error */
#define VUDC_EVENT_ERROR_USB (USBIP_EH_SHUTDOWN | USBIP_EH_UNUSABLE)
#define VUDC_EVENT_ERROR_MALLOC (USBIP_EH_SHUTDOWN | USBIP_EH_UNUSABLE)
#define VDEV_EVENT_REMOVED (USBIP_EH_SHUTDOWN | USBIP_EH_RESET | USBIP_EH_BYE)
#define VDEV_EVENT_DOWN (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
#define VDEV_EVENT_ERROR_TCP (USBIP_EH_SHUTDOWN | USBIP_EH_RESET)
#define VDEV_EVENT_ERROR_MALLOC (USBIP_EH_SHUTDOWN | USBIP_EH_UNUSABLE)
/* a common structure for stub_device and vhci_device */
struct usbip_device {
enum usbip_side side;
enum usbip_device_status status;
/* lock for status */
spinlock_t lock;
int sockfd;
struct socket *tcp_socket;
struct task_struct *tcp_rx;
struct task_struct *tcp_tx;
unsigned long event;
wait_queue_head_t eh_waitq;
struct eh_ops {
void (*shutdown)(struct usbip_device *);
void (*reset)(struct usbip_device *);
void (*unusable)(struct usbip_device *);
} eh_ops;
};
#define kthread_get_run(threadfn, data, namefmt, ...) \
({ \
struct task_struct *__k \
= kthread_create(threadfn, data, namefmt, ## __VA_ARGS__); \
if (!IS_ERR(__k)) { \
get_task_struct(__k); \
wake_up_process(__k); \
} \
__k; \
})
#define kthread_stop_put(k) \
do { \
kthread_stop(k); \
put_task_struct(k); \
} while (0)
/* usbip_common.c */
void usbip_dump_urb(struct urb *purb);
void usbip_dump_header(struct usbip_header *pdu);
int usbip_recv(struct socket *sock, void *buf, int size);
void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
int pack);
void usbip_header_correct_endian(struct usbip_header *pdu, int send);
struct usbip_iso_packet_descriptor*
usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen);
/* some members of urb must be substituted before. */
int usbip_recv_iso(struct usbip_device *ud, struct urb *urb);
void usbip_pad_iso(struct usbip_device *ud, struct urb *urb);
int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb);
/* usbip_event.c */
int usbip_init_eh(void);
void usbip_finish_eh(void);
int usbip_start_eh(struct usbip_device *ud);
void usbip_stop_eh(struct usbip_device *ud);
void usbip_event_add(struct usbip_device *ud, unsigned long event);
int usbip_event_happened(struct usbip_device *ud);
int usbip_in_eh(struct task_struct *task);
static inline int interface_to_busnum(struct usb_interface *interface)
{
struct usb_device *udev = interface_to_usbdev(interface);
return udev->bus->busnum;
}
static inline int interface_to_devnum(struct usb_interface *interface)
{
struct usb_device *udev = interface_to_usbdev(interface);
return udev->devnum;
}
#endif /* __USBIP_COMMON_H */