libvirt/src/xenconfig/xen_xm.c
John Ferlan cfbbeb36cf xen_xm: Resolve Coverity USE_AFTER_FREE
If virDomainDiskDefFree(disk) is called in 'skipdisk:', then it's possible
to either return to skipdisk without reallocating a new disk (via the if
condition just prior) or to end the loop having deleted the disk. Since
virDomainDiskDefFree() does not pass by reference, disk isn't changed in
this context, thus the possible issue.
2014-08-27 12:52:27 -04:00

428 lines
13 KiB
C

/*
* xen_xm.c: Xen XM parsing functions
*
* Copyright (C) 2006-2007, 2009-2014 Red Hat, Inc.
* Copyright (C) 2011 Univention GmbH
* Copyright (C) 2006 Daniel P. Berrange
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*
* Author: Daniel P. Berrange <berrange@redhat.com>
* Author: Markus Groß <gross@univention.de>
*/
#include <config.h>
#include "internal.h"
#include "virerror.h"
#include "virconf.h"
#include "viralloc.h"
#include "verify.h"
#include "xenxs_private.h"
#include "xen_xm.h"
#include "domain_conf.h"
#include "virstring.h"
#include "xen_common.h"
static int
xenParseXMDisk(virConfPtr conf, virDomainDefPtr def, int xendConfigVersion)
{
const char *str = NULL;
virDomainDiskDefPtr disk = NULL;
int hvm = STREQ(def->os.type, "hvm");
virConfValuePtr list = virConfGetValue(conf, "disk");
if (list && list->type == VIR_CONF_LIST) {
list = list->list;
while (list) {
char *head;
char *offset;
char *tmp;
const char *src;
if ((list->type != VIR_CONF_STRING) || (list->str == NULL))
goto skipdisk;
head = list->str;
if (!(disk = virDomainDiskDefNew()))
return -1;
/*
* Disks have 3 components, SOURCE,DEST-DEVICE,MODE
* eg, phy:/dev/HostVG/XenGuest1,xvda,w
* The SOURCE is usually prefixed with a driver type,
* and optionally driver sub-type
* The DEST-DEVICE is optionally post-fixed with disk type
*/
/* Extract the source file path*/
if (!(offset = strchr(head, ',')))
goto skipdisk;
if (offset == head) {
/* No source file given, eg CDROM with no media */
ignore_value(virDomainDiskSetSource(disk, NULL));
} else {
if (VIR_STRNDUP(tmp, head, offset - head) < 0)
goto cleanup;
if (virDomainDiskSetSource(disk, tmp) < 0) {
VIR_FREE(tmp);
goto cleanup;
}
VIR_FREE(tmp);
}
head = offset + 1;
/* Remove legacy ioemu: junk */
if (STRPREFIX(head, "ioemu:"))
head = head + 6;
/* Extract the dest device name */
if (!(offset = strchr(head, ',')))
goto skipdisk;
if (VIR_ALLOC_N(disk->dst, (offset - head) + 1) < 0)
goto cleanup;
if (virStrncpy(disk->dst, head, offset - head,
(offset - head) + 1) == NULL) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Dest file %s too big for destination"), head);
goto cleanup;
}
head = offset + 1;
/* Extract source driver type */
src = virDomainDiskGetSource(disk);
if (src) {
size_t len;
/* The main type phy:, file:, tap: ... */
if ((tmp = strchr(src, ':')) != NULL) {
len = tmp - src;
if (VIR_STRNDUP(tmp, src, len) < 0)
goto cleanup;
if (virDomainDiskSetDriver(disk, tmp) < 0) {
VIR_FREE(tmp);
goto cleanup;
}
VIR_FREE(tmp);
/* Strip the prefix we found off the source file name */
if (virDomainDiskSetSource(disk, src + len + 1) < 0)
goto cleanup;
src = virDomainDiskGetSource(disk);
}
/* And the sub-type for tap:XXX: type */
if (STREQ_NULLABLE(virDomainDiskGetDriver(disk), "tap")) {
char *driverType;
if (!(tmp = strchr(src, ':')))
goto skipdisk;
len = tmp - src;
if (VIR_STRNDUP(driverType, src, len) < 0)
goto cleanup;
if (STREQ(driverType, "aio"))
virDomainDiskSetFormat(disk, VIR_STORAGE_FILE_RAW);
else
virDomainDiskSetFormat(disk,
virStorageFileFormatTypeFromString(driverType));
VIR_FREE(driverType);
if (virDomainDiskGetFormat(disk) <= 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Unknown driver type %s"),
src);
goto cleanup;
}
/* Strip the prefix we found off the source file name */
if (virDomainDiskSetSource(disk, src + len + 1) < 0)
goto cleanup;
src = virDomainDiskGetSource(disk);
}
}
/* No source, or driver name, so fix to phy: */
if (!virDomainDiskGetDriver(disk) &&
virDomainDiskSetDriver(disk, "phy") < 0)
goto cleanup;
/* phy: type indicates a block device */
virDomainDiskSetType(disk,
STREQ(virDomainDiskGetDriver(disk), "phy") ?
VIR_STORAGE_TYPE_BLOCK :
VIR_STORAGE_TYPE_FILE);
/* Check for a :cdrom/:disk postfix */
disk->device = VIR_DOMAIN_DISK_DEVICE_DISK;
if ((tmp = strchr(disk->dst, ':')) != NULL) {
if (STREQ(tmp, ":cdrom"))
disk->device = VIR_DOMAIN_DISK_DEVICE_CDROM;
tmp[0] = '\0';
}
if (STRPREFIX(disk->dst, "xvd") || !hvm) {
disk->bus = VIR_DOMAIN_DISK_BUS_XEN;
} else if (STRPREFIX(disk->dst, "sd")) {
disk->bus = VIR_DOMAIN_DISK_BUS_SCSI;
} else {
disk->bus = VIR_DOMAIN_DISK_BUS_IDE;
}
if (STREQ(head, "r") ||
STREQ(head, "ro"))
disk->src->readonly = true;
else if ((STREQ(head, "w!")) ||
(STREQ(head, "!")))
disk->src->shared = true;
/* Maintain list in sorted order according to target device name */
if (VIR_APPEND_ELEMENT(def->disks, def->ndisks, disk) < 0)
goto cleanup;
skipdisk:
list = list->next;
virDomainDiskDefFree(disk);
disk = NULL;
}
}
if (hvm && xendConfigVersion == XEND_CONFIG_VERSION_3_0_2) {
if (xenConfigGetString(conf, "cdrom", &str, NULL) < 0)
goto cleanup;
if (str) {
if (!(disk = virDomainDiskDefNew()))
goto cleanup;
virDomainDiskSetType(disk, VIR_STORAGE_TYPE_FILE);
disk->device = VIR_DOMAIN_DISK_DEVICE_CDROM;
if (virDomainDiskSetDriver(disk, "file") < 0)
goto cleanup;
if (virDomainDiskSetSource(disk, str) < 0)
goto cleanup;
if (VIR_STRDUP(disk->dst, "hdc") < 0)
goto cleanup;
disk->bus = VIR_DOMAIN_DISK_BUS_IDE;
disk->src->readonly = true;
if (VIR_APPEND_ELEMENT(def->disks, def->ndisks, disk) < 0)
goto cleanup;
}
}
return 0;
cleanup:
virDomainDiskDefFree(disk);
return -1;
}
static int
xenFormatXMDisk(virConfValuePtr list,
virDomainDiskDefPtr disk,
int hvm,
int xendConfigVersion)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
virConfValuePtr val, tmp;
const char *src = virDomainDiskGetSource(disk);
int format = virDomainDiskGetFormat(disk);
const char *driver = virDomainDiskGetDriver(disk);
if (src) {
if (format) {
const char *type;
if (format == VIR_STORAGE_FILE_RAW)
type = "aio";
else
type = virStorageFileFormatTypeToString(format);
virBufferAsprintf(&buf, "%s:", driver);
if (STREQ(driver, "tap"))
virBufferAsprintf(&buf, "%s:", type);
} else {
switch (virDomainDiskGetType(disk)) {
case VIR_STORAGE_TYPE_FILE:
virBufferAddLit(&buf, "file:");
break;
case VIR_STORAGE_TYPE_BLOCK:
virBufferAddLit(&buf, "phy:");
break;
default:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unsupported disk type %s"),
virStorageTypeToString(virDomainDiskGetType(disk)));
goto cleanup;
}
}
virBufferAdd(&buf, src, -1);
}
virBufferAddLit(&buf, ",");
if (hvm && xendConfigVersion == XEND_CONFIG_VERSION_3_0_2)
virBufferAddLit(&buf, "ioemu:");
virBufferAdd(&buf, disk->dst, -1);
if (disk->device == VIR_DOMAIN_DISK_DEVICE_CDROM)
virBufferAddLit(&buf, ":cdrom");
if (disk->src->readonly)
virBufferAddLit(&buf, ",r");
else if (disk->src->shared)
virBufferAddLit(&buf, ",!");
else
virBufferAddLit(&buf, ",w");
if (disk->transient) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("transient disks not supported yet"));
return -1;
}
if (virBufferCheckError(&buf) < 0)
goto cleanup;
if (VIR_ALLOC(val) < 0)
goto cleanup;
val->type = VIR_CONF_STRING;
val->str = virBufferContentAndReset(&buf);
tmp = list->list;
while (tmp && tmp->next)
tmp = tmp->next;
if (tmp)
tmp->next = val;
else
list->list = val;
return 0;
cleanup:
virBufferFreeAndReset(&buf);
return -1;
}
static int
xenFormatXMDisks(virConfPtr conf, virDomainDefPtr def, int xendConfigVersion)
{
virConfValuePtr diskVal = NULL;
size_t i = 0;
int hvm = STREQ(def->os.type, "hvm");
if (VIR_ALLOC(diskVal) < 0)
goto cleanup;
diskVal->type = VIR_CONF_LIST;
diskVal->list = NULL;
for (i = 0; i < def->ndisks; i++) {
if (xendConfigVersion == XEND_CONFIG_VERSION_3_0_2 &&
def->disks[i]->device == VIR_DOMAIN_DISK_DEVICE_CDROM &&
def->disks[i]->dst &&
STREQ(def->disks[i]->dst, "hdc")) {
continue;
}
if (def->disks[i]->device == VIR_DOMAIN_DISK_DEVICE_FLOPPY)
continue;
if (xenFormatXMDisk(diskVal, def->disks[i],
hvm, xendConfigVersion) < 0)
goto cleanup;
}
if (diskVal->list != NULL) {
int ret = virConfSetValue(conf, "disk", diskVal);
diskVal = NULL;
if (ret < 0)
goto cleanup;
}
VIR_FREE(diskVal);
return 0;
cleanup:
virConfFreeValue(diskVal);
return -1;
}
/*
* Convert an XM config record into a virDomainDef object.
*/
virDomainDefPtr
xenParseXM(virConfPtr conf,
int xendConfigVersion,
virCapsPtr caps)
{
virDomainDefPtr def = NULL;
if (VIR_ALLOC(def) < 0)
return NULL;
def->virtType = VIR_DOMAIN_VIRT_XEN;
def->id = -1;
if (xenParseConfigCommon(conf, def, caps, xendConfigVersion) < 0)
goto cleanup;
if (xenParseXMDisk(conf, def, xendConfigVersion) < 0)
goto cleanup;
return def;
cleanup:
virDomainDefFree(def);
return NULL;
}
/* Computing the vcpu_avail bitmask works because MAX_VIRT_CPUS is
either 32, or 64 on a platform where long is big enough. */
verify(MAX_VIRT_CPUS <= sizeof(1UL) * CHAR_BIT);
/*
* Convert a virDomainDef object inot an XM config record.
*/
virConfPtr
xenFormatXM(virConnectPtr conn,
virDomainDefPtr def,
int xendConfigVersion)
{
virConfPtr conf = NULL;
if (!(conf = virConfNew()))
goto cleanup;
if (xenFormatConfigCommon(conf, def, conn, xendConfigVersion) < 0)
goto cleanup;
if (xenFormatXMDisks(conf, def, xendConfigVersion) < 0)
goto cleanup;
return conf;
cleanup:
if (conf)
virConfFree(conf);
return NULL;
}