Adding upstream version 256.upstream/256

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 43 insertions, 18 deletions

diff --git a/src/shared/machine-id-setup.c b/src/shared/machine-id-setup.c
index 3efba03..1a63794 100644
--- a/src/shared/machine-id-setup.c
+++ b/src/shared/machine-id-setup.c
@@ -5,6 +5,7 @@
 #include <sys/mount.h>
 #include <unistd.h>
 
+#include "sd-daemon.h"
 #include "sd-id128.h"
 
 #include "alloc-util.h"
@@ -12,6 +13,7 @@
 #include "creds-util.h"
 #include "fd-util.h"
 #include "id128-util.h"
+#include "initrd-util.h"
 #include "io-util.h"
 #include "log.h"
 #include "machine-id-setup.h"
@@ -46,13 +48,22 @@ static int acquire_machine_id_from_credential(sd_id128_t *ret) {
         return 0;
 }
 
-static int generate_machine_id(const char *root, sd_id128_t *ret) {
+static int acquire_machine_id(const char *root, sd_id128_t *ret) {
         _cleanup_close_ int fd = -EBADF;
         int r;
 
         assert(ret);
 
-        /* First, try reading the D-Bus machine id, unless it is a symlink */
+        /* First, try reading the machine ID from /run/machine-id, which may not be mounted on
+         * /etc/machine-id yet. This is important on switching root especially on soft-reboot, Otherwise,
+         * machine ID may be changed after the transition. */
+        if (isempty(root) && running_in_chroot() <= 0 &&
+            id128_read("/run/machine-id", ID128_FORMAT_PLAIN, ret) >= 0) {
+                log_info("Reusing machine ID stored in /run/machine-id.");
+                return 1; /* Indicate that the machine ID is reused. */
+        }
+
+        /* Then, try reading the D-Bus machine id, unless it is a symlink */
         fd = chase_and_open("/var/lib/dbus/machine-id", root, CHASE_PREFIX_ROOT | CHASE_NOFOLLOW, O_RDONLY|O_CLOEXEC|O_NOCTTY, NULL);
         if (fd >= 0 && id128_read_fd(fd, ID128_FORMAT_PLAIN | ID128_REFUSE_NULL, ret) >= 0) {
                 log_info("Initializing machine ID from D-Bus machine ID.");
@@ -61,9 +72,8 @@ static int generate_machine_id(const char *root, sd_id128_t *ret) {
 
         if (isempty(root) && running_in_chroot() <= 0) {
                 /* Let's use a system credential for the machine ID if we can */
-                r = acquire_machine_id_from_credential(ret);
-                if (r >= 0)
-                        return r;
+                if (acquire_machine_id_from_credential(ret) >= 0)
+                        return 0;
 
                 /* If that didn't work, see if we are running in a container,
                  * and a machine ID was passed in via $container_uuid the way
@@ -103,7 +113,7 @@ static int generate_machine_id(const char *root, sd_id128_t *ret) {
 int machine_id_setup(const char *root, bool force_transient, sd_id128_t machine_id, sd_id128_t *ret) {
         const char *etc_machine_id, *run_machine_id;
         _cleanup_close_ int fd = -EBADF;
-        bool writable;
+        bool writable, write_run_machine_id = true;
         int r;
 
         etc_machine_id = prefix_roota(root, "/etc/machine-id");
@@ -141,13 +151,14 @@ int machine_id_setup(const char *root, bool force_transient, sd_id128_t machine_
         if (sd_id128_is_null(machine_id)) {
 
                 /* Try to read any existing machine ID */
-                if (id128_read_fd(fd, ID128_FORMAT_PLAIN, ret) >= 0)
-                        return 0;
+                if (id128_read_fd(fd, ID128_FORMAT_PLAIN, &machine_id) >= 0)
+                        goto finish;
 
-                /* Hmm, so, the id currently stored is not useful, then let's generate one */
-                r = generate_machine_id(root, &machine_id);
+                /* Hmm, so, the id currently stored is not useful, then let's acquire one. */
+                r = acquire_machine_id(root, &machine_id);
                 if (r < 0)
                         return r;
+                write_run_machine_id = !r;
         }
 
         if (writable) {
@@ -185,11 +196,13 @@ int machine_id_setup(const char *root, bool force_transient, sd_id128_t machine_
 
         run_machine_id = prefix_roota(root, "/run/machine-id");
 
-        WITH_UMASK(0022)
-                r = id128_write(run_machine_id, ID128_FORMAT_PLAIN, machine_id);
-        if (r < 0) {
-                (void) unlink(run_machine_id);
-                return log_error_errno(r, "Cannot write %s: %m", run_machine_id);
+        if (write_run_machine_id) {
+                WITH_UMASK(0022)
+                        r = id128_write(run_machine_id, ID128_FORMAT_PLAIN, machine_id);
+                if (r < 0) {
+                        (void) unlink(run_machine_id);
+                        return log_error_errno(r, "Cannot write %s: %m", run_machine_id);
+                }
         }
 
         /* And now, let's mount it over */
@@ -207,6 +220,9 @@ int machine_id_setup(const char *root, bool force_transient, sd_id128_t machine_
                 return r;
 
 finish:
+        if (!in_initrd())
+                (void) sd_notifyf(/* unset_environment= */ false, "X_SYSTEMD_MACHINE_ID=" SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL(machine_id));
+
         if (ret)
                 *ret = machine_id;
 
@@ -237,7 +253,7 @@ int machine_id_commit(const char *root) {
 
         etc_machine_id = prefix_roota(root, "/etc/machine-id");
 
-        r = path_is_mount_point(etc_machine_id, NULL, 0);
+        r = path_is_mount_point(etc_machine_id);
         if (r < 0)
                 return log_error_errno(r, "Failed to determine whether %s is a mount point: %m", etc_machine_id);
         if (r == 0) {
@@ -265,7 +281,12 @@ int machine_id_commit(const char *root) {
         fd = safe_close(fd);
 
         /* Store current mount namespace */
-        r = namespace_open(0, NULL, &initial_mntns_fd, NULL, NULL, NULL);
+        r = namespace_open(0,
+                           /* ret_pidns_fd = */ NULL,
+                           &initial_mntns_fd,
+                           /* ret_netns_fd = */ NULL,
+                           /* ret_userns_fd = */ NULL,
+                           /* ret_root_fd = */ NULL);
         if (r < 0)
                 return log_error_errno(r, "Can't fetch current mount namespace: %m");
 
@@ -284,7 +305,11 @@ int machine_id_commit(const char *root) {
                 return log_error_errno(r, "Cannot write %s. This is mandatory to get a persistent machine ID: %m", etc_machine_id);
 
         /* Return to initial namespace and proceed a lazy tmpfs unmount */
-        r = namespace_enter(-1, initial_mntns_fd, -1, -1, -1);
+        r = namespace_enter(/* pidns_fd = */ -EBADF,
+                            initial_mntns_fd,
+                            /* netns_fd = */ -EBADF,
+                            /* userns_fd = */ -EBADF,
+                            /* root_fd = */ -EBADF);
         if (r < 0)
                 return log_warning_errno(r, "Failed to switch back to initial mount namespace: %m.\nWe'll keep transient %s file until next reboot.", etc_machine_id);