1:26 a.m.
This patch introduces new helper function
virLXCControllerSetupUserns, in this function,
we set the files uid_map and gid_map of process
libvirt_lxc.
lxcContainerSetUserns is used for creating cred for
tasks running in container. Since after setuid/setgid,
we may be a new user. This patch calls lxcContainerSetUserns
at first to make sure the new created files belong to
right user.
Signed-off-by: Gao feng <gaofeng(a)cn.fujitsu.com>
---
src/lxc/lxc_container.c | 55 ++++++++++++++++++++++++++++++----------
src/lxc/lxc_controller.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 107 insertions(+), 14 deletions(-)
diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c
index 1d7bc1e..5c66ae3 100644
--- a/src/lxc/lxc_container.c
+++ b/src/lxc/lxc_container.c
@@ -329,6 +329,29 @@ int lxcContainerWaitForContinue(int control)
/**
+ * lxcContainerSetUserns:
+ *
+ * This function calls setuid and setgid to create proper
+ * cred for tasks running in container.
+ *
+ * Returns 0 on success or -1 in case of error
+ */
+static int lxcContainerSetUserns(virDomainDefPtr def)
+{
+ if (def->os.userns != VIR_DOMAIN_USER_NS_ENABLED)
+ return 0;
+
+ if (virSetUIDGID(def->os.uidmap.first,
+ def->os.gidmap.first) < 0) {
+ virReportSystemError(errno, "%s",
+ _("setuid or setgid failed"));
+ return -1;
+ }
+
+ return 0;
+}
+
+/**
* lxcContainerRenameAndEnableInterfaces:
* @nveths: number of interfaces
* @veths: interface names
@@ -2221,6 +2244,24 @@ static int lxcContainerChild(void *data)
}
}
+ if (!virFileExists(vmDef->os.init)) {
+ virReportSystemError(errno,
+ _("cannot find init path '%s' relative to container
root"),
+ vmDef->os.init);
+ goto cleanup;
+ }
+
+ /* Wait for interface devices to show up */
+ if (lxcContainerWaitForContinue(argv->monitor) < 0) {
+ virReportSystemError(errno, "%s",
+ _("Failed to read the container continue
message"));
+ goto cleanup;
+ }
+ VIR_DEBUG("Received container continue message");
+
+ if (lxcContainerSetUserns(vmDef) < 0)
+ goto cleanup;
+
VIR_DEBUG("Container TTY path: %s", ttyPath);
ttyfd = open(ttyPath, O_RDWR|O_NOCTTY);
@@ -2236,20 +2277,6 @@ static int lxcContainerChild(void *data)
argv->securityDriver) < 0)
goto cleanup;
- if (!virFileExists(vmDef->os.init)) {
- virReportSystemError(errno,
- _("cannot find init path '%s' relative to container
root"),
- vmDef->os.init);
- goto cleanup;
- }
-
- /* Wait for interface devices to show up */
- if (lxcContainerWaitForContinue(argv->monitor) < 0) {
- virReportSystemError(errno, "%s",
- _("Failed to read the container continue
message"));
- goto cleanup;
- }
- VIR_DEBUG("Received container continue message");
/* rename and enable interfaces */
if (lxcContainerRenameAndEnableInterfaces(!!(vmDef->features &
diff --git a/src/lxc/lxc_controller.c b/src/lxc/lxc_controller.c
index 15aa334..f17142f 100644
--- a/src/lxc/lxc_controller.c
+++ b/src/lxc/lxc_controller.c
@@ -1028,6 +1028,69 @@ cleanup2:
}
+/**
+ * virLXCControllerSetupUserns
+ *
+ * Set proc files for user namespace
+ *
+ * Returns 0 on success or -1 in case of error
+ */
+static int virLXCControllerSetupUserns(virLXCControllerPtr ctrl)
+{
+ char *uid_map = NULL;
+ char *gid_map = NULL;
+ char *uidmap_value = NULL;
+ char *gidmap_value = NULL;
+ int ret = -1;
+
+ if (ctrl->def->os.userns != VIR_DOMAIN_USER_NS_ENABLED)
+ return 0;
+
+ if (virAsprintf(&uid_map, "/proc/%d/uid_map", ctrl->initpid) <
0)
+ goto cleanup;
+
+ if (virAsprintf(&gid_map, "/proc/%d/gid_map", ctrl->initpid) <
0)
+ goto cleanup;
+
+ if (virAsprintf(&uidmap_value, "%u %u %u",
+ ctrl->def->os.uidmap.first,
+ ctrl->def->os.uidmap.low_first,
+ ctrl->def->os.uidmap.count) < 0)
+ goto cleanup;
+
+ if (virAsprintf(&gidmap_value, "%u %u %u",
+ ctrl->def->os.gidmap.first,
+ ctrl->def->os.gidmap.low_first,
+ ctrl->def->os.gidmap.count) < 0)
+ goto cleanup;
+
+ if (virFileWriteStr(uid_map, uidmap_value, 0) < 0) {
+ if (errno == -ENOENT)
+ virReportSystemError(errno,
+ _("%s doesn't exist, please disable
userns"),
+ uid_map);
+ virReportSystemError(errno, _("unable write to %s"), uid_map);
+ goto cleanup;
+ }
+
+ if (virFileWriteStr(gid_map, gidmap_value, 0) < 0) {
+ if (errno == -ENOENT)
+ virReportSystemError(errno,
+ _("%s doesn't exist, please disable
userns"),
+ gid_map);
+ virReportSystemError(errno, _("unable write to %s"), gid_map);
+ goto cleanup;
+ }
+
+ ret = 0;
+cleanup:
+ VIR_FREE(uidmap_value);
+ VIR_FREE(gidmap_value);
+ VIR_FREE(uid_map);
+ VIR_FREE(gid_map);
+ return ret;
+}
+
/**
* virLXCControllerMoveInterfaces
@@ -1454,6 +1517,9 @@ virLXCControllerRun(virLXCControllerPtr ctrl)
VIR_FORCE_CLOSE(control[1]);
VIR_FORCE_CLOSE(containerhandshake[1]);
+ if (virLXCControllerSetupUserns(ctrl) < 0)
+ goto cleanup;
+
if (virLXCControllerMoveInterfaces(ctrl) < 0)
goto cleanup;
--
1.7.11.7