Merge pull request #10912 from poettering/gpt-root-rw

make sure to propagate GPT root partition r/w flag into mount r/w flag

1 files changed, 51 insertions, 7 deletions

diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index e9f3d7dab2..d9e29c47f3 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -39,7 +39,7 @@
 static const char *arg_dest = NULL;
 static bool arg_enabled = true;
 static bool arg_root_enabled = true;
-static bool arg_root_rw = false;
+static int arg_root_rw = -1;
 
 static int add_cryptsetup(const char *id, const char *what, bool rw, bool require, char **device) {
         _cleanup_free_ char *e = NULL, *n = NULL, *d = NULL, *id_escaped = NULL, *what_escaped = NULL;
@@ -446,6 +446,43 @@ static int add_esp(DissectedPartition *p) {
 }
 #endif
 
+static int add_root_rw(DissectedPartition *p) {
+        const char *path;
+        int r;
+
+        assert(p);
+
+        if (in_initrd()) {
+                log_debug("In initrd, not generating drop-in for systemd-remount-fs.service.");
+                return 0;
+        }
+
+        if (arg_root_rw >= 0) {
+                log_debug("Parameter ro/rw specified on kernel command line, not generating drop-in for systemd-remount-fs.service.");
+                return 0;
+        }
+
+        if (!p->rw) {
+                log_debug("Root partition marked read-only in GPT partition table, not generating drop-in for systemd-remount-fs.service.");
+                return 0;
+        }
+
+        path = strjoina(arg_dest, "/systemd-remount-fs.service.d/50-remount-rw.conf");
+        (void) mkdir_parents(path, 0755);
+
+        r = write_string_file(path,
+                              "# Automatically generated by systemd-gpt-generator\n\n"
+                              "[Unit]\n"
+                              "ConditionPathExists=\n\n" /* We need to turn off the ConditionPathExist= in the main unit file */
+                              "[Service]\n"
+                              "Environment=SYSTEMD_REMOUNT_ROOT_RW=1\n",
+                              WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_NOFOLLOW);
+        if (r < 0)
+                return log_error_errno(r, "Failed to write drop-in file %s: %m", path);
+
+        return 0;
+}
+
 static int open_parent(dev_t devnum, int *ret) {
         _cleanup_(sd_device_unrefp) sd_device *d = NULL;
         const char *name, *devtype, *node;
@@ -550,6 +587,12 @@ static int enumerate_partitions(dev_t devnum) {
                         r = k;
         }
 
+        if (m->partitions[PARTITION_ROOT].found) {
+                k = add_root_rw(m->partitions + PARTITION_ROOT);
+                if (k < 0)
+                        r = k;
+        }
+
         return r;
 }
 
@@ -558,7 +601,8 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
 
         assert(key);
 
-        if (STR_IN_SET(key, "systemd.gpt_auto", "rd.systemd.gpt_auto")) {
+        if (proc_cmdline_key_streq(key, "systemd.gpt_auto") ||
+            proc_cmdline_key_streq(key, "rd.systemd.gpt_auto")) {
 
                 r = value ? parse_boolean(value) : 1;
                 if (r < 0)
@@ -566,7 +610,7 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
                 else
                         arg_enabled = r;
 
-        } else if (streq(key, "root")) {
+        } else if (proc_cmdline_key_streq(key, "root")) {
 
                 if (proc_cmdline_value_missing(key, value))
                         return 0;
@@ -576,7 +620,7 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
 
                 arg_root_enabled = streq(value, "gpt-auto");
 
-        } else if (streq(key, "roothash")) {
+        } else if (proc_cmdline_key_streq(key, "roothash")) {
 
                 if (proc_cmdline_value_missing(key, value))
                         return 0;
@@ -585,9 +629,9 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
 
                 arg_root_enabled = false;
 
-        } else if (streq(key, "rw") && !value)
+        } else if (proc_cmdline_key_streq(key, "rw") && !value)
                 arg_root_rw = true;
-        else if (streq(key, "ro") && !value)
+        else if (proc_cmdline_key_streq(key, "ro") && !value)
                 arg_root_rw = false;
 
         return 0;
@@ -639,7 +683,7 @@ static int add_root_mount(void) {
                         "/dev/gpt-auto-root",
                         in_initrd() ? "/sysroot" : "/",
                         NULL,
-                        arg_root_rw,
+                        arg_root_rw > 0,
                         NULL,
                         "Root Partition",
                         in_initrd() ? SPECIAL_INITRD_ROOT_FS_TARGET : SPECIAL_LOCAL_FS_TARGET);