freebsd-skq/sys/geom/gate/g_gate.h
Mikolaj Golub baf63f65ae In g_gate_create() there is a window between when g_gate_softc is
registered in g_gate_units array and when its sc_provider field is
filled. If during this period g_gate_units is accessed by another
thread that is checking for provider name collision the crash is
possible.

Fix this by adding sc_name field to struct g_gate_softc. In
g_gate_create() when g_gate_softc is created but sc_provider is still
not sc_name points to provider name stored in the local array.

Approved by:	pjd (mentor)
Reported by:	Freddie Cash <fjwcash@gmail.com>
MFC after:	1 week
2011-03-27 19:56:55 +00:00

162 lines
4.7 KiB
C

/*-
* Copyright (c) 2004-2009 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _G_GATE_H_
#define _G_GATE_H_
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/queue.h>
#include <geom/geom.h>
#define G_GATE_CLASS_NAME "GATE"
#define G_GATE_PROVIDER_NAME "ggate"
#define G_GATE_MOD_NAME "ggate"
#define G_GATE_CTL_NAME "ggctl"
#define G_GATE_VERSION 2
/*
* Maximum number of request that can be stored in
* the queue when there are no workers.
*/
#define G_GATE_MAX_QUEUE_SIZE 4096
#define G_GATE_FLAG_READONLY 0x0001
#define G_GATE_FLAG_WRITEONLY 0x0002
#define G_GATE_FLAG_DESTROY 0x1000
#define G_GATE_USERFLAGS (G_GATE_FLAG_READONLY | G_GATE_FLAG_WRITEONLY)
/*
* Pick unit number automatically in /dev/ggate<unit>.
*/
#define G_GATE_UNIT_AUTO (-1)
/*
* Full provider name is given, so don't use ggate<unit>.
*/
#define G_GATE_NAME_GIVEN (-2)
#define G_GATE_CMD_CREATE _IOWR('m', 0, struct g_gate_ctl_create)
#define G_GATE_CMD_DESTROY _IOWR('m', 1, struct g_gate_ctl_destroy)
#define G_GATE_CMD_CANCEL _IOWR('m', 2, struct g_gate_ctl_cancel)
#define G_GATE_CMD_START _IOWR('m', 3, struct g_gate_ctl_io)
#define G_GATE_CMD_DONE _IOWR('m', 4, struct g_gate_ctl_io)
#define G_GATE_INFOSIZE 2048
#ifdef _KERNEL
/*
* 'P:' means 'Protected by'.
*/
struct g_gate_softc {
char *sc_name; /* P: (read-only) */
int sc_unit; /* P: (read-only) */
int sc_ref; /* P: g_gate_list_mtx */
struct g_provider *sc_provider; /* P: (read-only) */
uint32_t sc_flags; /* P: sc_queue_mtx */
struct bio_queue_head sc_inqueue; /* P: sc_queue_mtx */
struct bio_queue_head sc_outqueue; /* P: sc_queue_mtx */
struct mtx sc_queue_mtx;
uint32_t sc_queue_count; /* P: sc_queue_mtx */
uint32_t sc_queue_size; /* P: (read-only) */
u_int sc_timeout; /* P: (read-only) */
struct callout sc_callout; /* P: (modified only
from callout
thread) */
uintptr_t sc_seq; /* P: (modified only
from g_down
thread) */
LIST_ENTRY(g_gate_softc) sc_next; /* P: g_gate_list_mtx */
char sc_info[G_GATE_INFOSIZE]; /* P: (read-only) */
};
#define G_GATE_DEBUG(lvl, ...) do { \
if (g_gate_debug >= (lvl)) { \
printf("GEOM_GATE"); \
if (g_gate_debug > 0) \
printf("[%u]", lvl); \
printf(": "); \
printf(__VA_ARGS__); \
printf("\n"); \
} \
} while (0)
#define G_GATE_LOGREQ(lvl, bp, ...) do { \
if (g_gate_debug >= (lvl)) { \
printf("GEOM_GATE"); \
if (g_gate_debug > 0) \
printf("[%u]", lvl); \
printf(": "); \
printf(__VA_ARGS__); \
printf(" "); \
g_print_bio(bp); \
printf("\n"); \
} \
} while (0)
#endif /* !_KERNEL */
struct g_gate_ctl_create {
u_int gctl_version;
off_t gctl_mediasize;
u_int gctl_sectorsize;
u_int gctl_flags;
u_int gctl_maxcount;
u_int gctl_timeout;
char gctl_name[NAME_MAX];
char gctl_info[G_GATE_INFOSIZE];
int gctl_unit; /* in/out */
};
struct g_gate_ctl_destroy {
u_int gctl_version;
int gctl_unit;
int gctl_force;
char gctl_name[NAME_MAX];
};
struct g_gate_ctl_cancel {
u_int gctl_version;
int gctl_unit;
uintptr_t gctl_seq;
char gctl_name[NAME_MAX];
};
struct g_gate_ctl_io {
u_int gctl_version;
int gctl_unit;
uintptr_t gctl_seq;
u_int gctl_cmd;
off_t gctl_offset;
off_t gctl_length;
void *gctl_data;
int gctl_error;
};
#endif /* !_G_GATE_H_ */