openkylin
/
libvirt
mirror of https://gitee.com/openkylin/libvirt.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

util: netdevbridge: fall back to ioctl from sysfs 

There are certain cases e.g. containers where the sysfs path might
exists, but might fail. Unfortunately the exact restrictions are only
known to libvirt when trying to write to it so we need to try it.

But in case it fails there is no need to fully abort, in those cases try
to fall back to the older ioctl interface which can still work.

That makes setting up a bridge in unprivileged LXD containers work.

Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1802906

Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Laine Stump <laine@laine.org>
Reported-by: Brian Candler <b.candler@pobox.com>
This commit is contained in:
Christian Ehrhardt 2018-11-20 08:55:49 +01:00
parent fd54e4fdc8
commit 6aa75b9462
No known key found for this signature in database
GPG Key ID: BA3E29338280B242
1 changed files with 26 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
src/util/virnetdevbridge.c
View File

@ -28,6 +28,7 @@
#include "virutil.h"
#include "virfile.h"
#include "viralloc.h"
#include "virlog.h"
#include "intprops.h"
#include "virstring.h"
@ -74,6 +75,7 @@
#define VIR_FROM_THIS VIR_FROM_NONE
VIR_LOG_INIT("util.netdevbridge");
#if defined(HAVE_BSD_BRIDGE_MGMT)
static int virNetDevBridgeCmd(const char *brname,
@ -113,6 +115,8 @@ static int virNetDevBridgeCmd(const char *brname,
* or by ioctl on older kernels. Perhaps we could just use
* ioctl for every kernel, but its not clear what the long
* term lifespan of the ioctl interface is...
* Fall back to ioctl if sysfs interface is not available or
* failing (e.g. due to container isolation).
*/
static int virNetDevBridgeSet(const char *brname,
const char *paramname, /* sysfs param name */
@ -128,29 +132,29 @@ static int virNetDevBridgeSet(const char *brname,
if (virFileExists(path)) {
char valuestr[INT_BUFSIZE_BOUND(value)];
snprintf(valuestr, sizeof(valuestr), "%lu", value);
if (virFileWriteStr(path, valuestr, 0) < 0) {
virReportSystemError(errno,
_("Unable to set bridge %s %s"), brname, paramname);
return -1;
}
if (virFileWriteStr(path, valuestr, 0) >= 0)
return 0;
VIR_DEBUG("Unable to set bridge %s %s via sysfs", brname, paramname);
}
unsigned long paramid;
if (STREQ(paramname, "stp_state")) {
paramid = BRCTL_SET_BRIDGE_STP_STATE;
} else if (STREQ(paramname, "forward_delay")) {
paramid = BRCTL_SET_BRIDGE_FORWARD_DELAY;
} else {
unsigned long paramid;
if (STREQ(paramname, "stp_state")) {
paramid = BRCTL_SET_BRIDGE_STP_STATE;
} else if (STREQ(paramname, "forward_delay")) {
paramid = BRCTL_SET_BRIDGE_FORWARD_DELAY;
} else {
virReportSystemError(EINVAL,
_("Unable to set bridge %s %s"), brname, paramname);
return -1;
}
unsigned long args[] = { paramid, value, 0, 0 };
ifr->ifr_data = (char*)&args;
if (ioctl(fd, SIOCDEVPRIVATE, ifr) < 0) {
virReportSystemError(errno,
_("Unable to set bridge %s %s"), brname, paramname);
return -1;
}
virReportSystemError(EINVAL,
_("Unable to set bridge %s %s via ioctl"),
brname, paramname);
return -1;
}
unsigned long args[] = { paramid, value, 0, 0 };
ifr->ifr_data = (char*)&args;
if (ioctl(fd, SIOCDEVPRIVATE, ifr) < 0) {
virReportSystemError(errno,
_("Failed to set bridge %s %s via ioctl"),
brname, paramname);
return -1;
}
return 0;