9:59 a.m.
Separate the guest created QEMU monitor socket location
from the libvirtd create XML / PID data files, to improve
security separation when running QEMU non-root
* libvirt.spec.in: Leave /var/run/libvirt/qemu as root:root
* src/qemu_conf.h: Add libDir and cacheDir directory paths
* src/qemu_driver.c: Move QEMU monitor socket from
stateDir to libDir to avoid making security critical directory
accessible to QEMU guests.
* src/util.c: Delay running hook till after damonizing to
ensure pidfile is still written before changing UID/GID
---
libvirt.spec.in | 2 +-
src/qemu_conf.h | 6 ++++++
src/qemu_driver.c | 39 ++++++++++++++++++++++++++++++++++-----
src/util.c | 8 ++++----
4 files changed, 45 insertions(+), 10 deletions(-)
diff --git a/libvirt.spec.in b/libvirt.spec.in
index 067b835..71d2896 100644
--- a/libvirt.spec.in
+++ b/libvirt.spec.in
@@ -503,7 +503,7 @@ fi
%dir %attr(0700, root, root) %{_localstatedir}/cache/libvirt/
%if %{with_qemu}
-%dir %attr(0700, %{qemu_user}, %{qemu_group}) %{_localstatedir}/run/libvirt/qemu/
+%dir %attr(0700, root, root) %{_localstatedir}/run/libvirt/qemu/
%dir %attr(0700, %{qemu_user}, %{qemu_group}) %{_localstatedir}/lib/libvirt/qemu/
%dir %attr(0700, %{qemu_user}, %{qemu_group}) %{_localstatedir}/cache/libvirt/qemu/
%endif
diff --git a/src/qemu_conf.h b/src/qemu_conf.h
index a126dac..35529cc 100644
--- a/src/qemu_conf.h
+++ b/src/qemu_conf.h
@@ -88,10 +88,16 @@ struct qemud_driver {
virDomainObjList domains;
brControl *brctl;
+ /* These four directories are ones libvirtd uses (so must be root:root
+ * to avoid security risk from QEMU processes */
char *configDir;
char *autostartDir;
char *logDir;
char *stateDir;
+ /* These two directories are ones QEMU processes use (so must match
+ * the QEMU user/group */
+ char *libDir;
+ char *cacheDir;
unsigned int vncTLS : 1;
unsigned int vncTLSx509verify : 1;
unsigned int vncSASL : 1;
diff --git a/src/qemu_driver.c b/src/qemu_driver.c
index eb22940..c561c06 100644
--- a/src/qemu_driver.c
+++ b/src/qemu_driver.c
@@ -71,9 +71,6 @@
#define VIR_FROM_THIS VIR_FROM_QEMU
-/* For storing short-lived temporary files. */
-#define TEMPDIR LOCAL_STATE_DIR "/cache/libvirt/qemu"
-
#define QEMU_CMD_PROMPT "\n(qemu) "
#define QEMU_PASSWD_PROMPT "Password: "
@@ -477,6 +474,14 @@ qemudStartup(int privileged) {
if (virAsprintf(&qemu_driver->stateDir,
"%s/run/libvirt/qemu", LOCAL_STATE_DIR) == -1)
goto out_of_memory;
+
+ if (virAsprintf(&qemu_driver->libDir,
+ "%s/lib/libvirt/qemu", LOCAL_STATE_DIR) == -1)
+ goto out_of_memory;
+
+ if (virAsprintf(&qemu_driver->cacheDir,
+ "%s/cache/libvirt/qemu", LOCAL_STATE_DIR) == -1)
+ goto out_of_memory;
} else {
uid_t uid = geteuid();
char *userdir = virGetUserDirectory(NULL, uid);
@@ -497,6 +502,10 @@ qemudStartup(int privileged) {
if (virAsprintf(&qemu_driver->stateDir, "%s/qemu/run", base) ==
-1)
goto out_of_memory;
+ if (virAsprintf(&qemu_driver->libDir, "%s/qemu/lib", base) ==
-1)
+ goto out_of_memory;
+ if (virAsprintf(&qemu_driver->cacheDir, "%s/qemu/cache", base)
== -1)
+ goto out_of_memory;
}
if (virFileMakePath(qemu_driver->stateDir) < 0) {
@@ -505,6 +514,18 @@ qemudStartup(int privileged) {
qemu_driver->stateDir, virStrerror(errno, ebuf, sizeof ebuf));
goto error;
}
+ if (virFileMakePath(qemu_driver->libDir) < 0) {
+ char ebuf[1024];
+ VIR_ERROR(_("Failed to create lib dir '%s': %s\n"),
+ qemu_driver->libDir, virStrerror(errno, ebuf, sizeof ebuf));
+ goto error;
+ }
+ if (virFileMakePath(qemu_driver->cacheDir) < 0) {
+ char ebuf[1024];
+ VIR_ERROR(_("Failed to create cache dir '%s': %s\n"),
+ qemu_driver->cacheDir, virStrerror(errno, ebuf, sizeof ebuf));
+ goto error;
+ }
/* Configuration paths are either ~/.libvirt/qemu/... (session) or
* /etc/libvirt/qemu/... (system).
@@ -668,6 +689,8 @@ qemudShutdown(void) {
VIR_FREE(qemu_driver->configDir);
VIR_FREE(qemu_driver->autostartDir);
VIR_FREE(qemu_driver->stateDir);
+ VIR_FREE(qemu_driver->libDir);
+ VIR_FREE(qemu_driver->cacheDir);
VIR_FREE(qemu_driver->vncTLSx509certdir);
VIR_FREE(qemu_driver->vncListen);
VIR_FREE(qemu_driver->vncPassword);
@@ -1942,7 +1965,7 @@ qemuPrepareMonitorChr(virConnectPtr conn,
monitor_chr->data.nix.listen = 1;
if (virAsprintf(&monitor_chr->data.nix.path, "%s/%s.monitor",
- driver->stateDir, vm) < 0) {
+ driver->libDir, vm) < 0) {
virReportOOMError(conn);
return -1;
}
@@ -6540,7 +6563,7 @@ qemudDomainMemoryPeek (virDomainPtr dom,
struct qemud_driver *driver = dom->conn->privateData;
virDomainObjPtr vm;
char cmd[256], *info = NULL;
- char tmp[] = TEMPDIR "/qemu.mem.XXXXXX";
+ char *tmp = NULL;
int fd = -1, ret = -1;
qemuDriverLock(driver);
@@ -6567,6 +6590,11 @@ qemudDomainMemoryPeek (virDomainPtr dom,
goto cleanup;
}
+ if (virAsprintf(&tmp, driver->cacheDir, "/qemu.mem.XXXXXX") < 0)
{
+ virReportOOMError(dom->conn);
+ goto cleanup;
+ }
+
/* Create a temporary filename. */
if ((fd = mkstemp (tmp)) == -1) {
virReportSystemError (dom->conn, errno,
@@ -6600,6 +6628,7 @@ qemudDomainMemoryPeek (virDomainPtr dom,
ret = 0;
cleanup:
+ VIR_FREE(tmp);
VIR_FREE(info);
if (fd >= 0) close (fd);
unlink (tmp);
diff --git a/src/util.c b/src/util.c
index 0d4f3fa..ab296d8 100644
--- a/src/util.c
+++ b/src/util.c
@@ -509,10 +509,6 @@ __virExec(virConnectPtr conn,
childerr != childout)
close(childerr);
- if (hook)
- if ((hook)(data) != 0)
- _exit(1);
-
/* Daemonize as late as possible, so the parent process can detect
* the above errors with wait* */
if (flags & VIR_EXEC_DAEMON) {
@@ -549,6 +545,10 @@ __virExec(virConnectPtr conn,
}
}
+ if (hook)
+ if ((hook)(data) != 0)
+ _exit(1);
+
/* The steps above may need todo something privileged, so
* we delay clearing capabilities until the last minute */
if ((flags & VIR_EXEC_CLEAR_CAPS) &&
--
1.6.2.5