Merge pull request #4879 from poettering/systemd

9 files changed, 220 insertions, 87 deletions

diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index dc13025115..d2d18f13f0 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -2361,6 +2361,7 @@ int cg_enable_everywhere(CGroupMask supported, CGroupMask mask, const char *p) {
 bool cg_is_unified_wanted(void) {
         static thread_local int wanted = -1;
         int r, unified;
+        bool b;
 
         /* If the hierarchy is already mounted, then follow whatever
          * was chosen for it. */
@@ -2374,20 +2375,11 @@ bool cg_is_unified_wanted(void) {
         if (wanted >= 0)
                 return wanted;
 
-        r = get_proc_cmdline_key("systemd.unified_cgroup_hierarchy", NULL);
-        if (r > 0)
-                return (wanted = true);
-        else {
-                _cleanup_free_ char *value = NULL;
-
-                r = get_proc_cmdline_key("systemd.unified_cgroup_hierarchy=", &value);
-                if (r < 0)
-                        return false;
-                if (r == 0)
-                        return (wanted = false);
+        r = proc_cmdline_get_bool("systemd.unified_cgroup_hierarchy", &b);
+        if (r < 0)
+                return false;
 
-                return (wanted = parse_boolean(value) > 0);
-        }
+        return (wanted = r > 0 ? b : false);
 }
 
 bool cg_is_legacy_wanted(void) {
@@ -2397,6 +2389,7 @@ bool cg_is_legacy_wanted(void) {
 bool cg_is_unified_systemd_controller_wanted(void) {
         static thread_local int wanted = -1;
         int r, unified;
+        bool b;
 
         /* If the unified hierarchy is requested in full, no need to
          * bother with this. */
@@ -2415,23 +2408,11 @@ bool cg_is_unified_systemd_controller_wanted(void) {
         if (wanted >= 0)
                 return wanted;
 
-        r = get_proc_cmdline_key("systemd.legacy_systemd_cgroup_controller", NULL);
-        if (r > 0)
-                wanted = false;
-        else {
-                _cleanup_free_ char *value = NULL;
-
-                r = get_proc_cmdline_key("systemd.legacy_systemd_cgroup_controller=", &value);
-                if (r < 0)
-                        return false;
-
-                if (r == 0)
-                        wanted = false;
-                else
-                        wanted = parse_boolean(value) <= 0;
-        }
+        r = proc_cmdline_get_bool("systemd.legacy_systemd_cgroup_controller", &b);
+        if (r < 0)
+                return false;
 
-        return wanted;
+        return (wanted = r > 0 ? b : false);
 }
 
 bool cg_is_legacy_systemd_controller_wanted(void) {
diff --git a/src/basic/fs-util.c b/src/basic/fs-util.c
index 5b23269109..e31fa2711a 100644
--- a/src/basic/fs-util.c
+++ b/src/basic/fs-util.c
@@ -799,8 +799,10 @@ int chase_symlinks(const char *path, const char *original_root, unsigned flags,
                         return -ENOMEM;
         }
 
-        *ret = done;
-        done = NULL;
+        if (ret) {
+                *ret = done;
+                done = NULL;
+        }
 
         return exists;
 }
diff --git a/src/basic/hexdecoct.c b/src/basic/hexdecoct.c
index c5bda6c4d6..6843aedd0a 100644
--- a/src/basic/hexdecoct.c
+++ b/src/basic/hexdecoct.c
@@ -97,6 +97,9 @@ int unhexmem(const char *p, size_t l, void **mem, size_t *len) {
         assert(len);
         assert(p);
 
+        if (l % 2 != 0)
+                return -EINVAL;
+
         z = r = malloc((l + 1) / 2 + 1);
         if (!r)
                 return -ENOMEM;
@@ -107,12 +110,10 @@ int unhexmem(const char *p, size_t l, void **mem, size_t *len) {
                 a = unhexchar(x[0]);
                 if (a < 0)
                         return a;
-                else if (x+1 < p + l) {
-                        b = unhexchar(x[1]);
-                        if (b < 0)
-                                return b;
-                } else
-                        b = 0;
+
+                b = unhexchar(x[1]);
+                if (b < 0)
+                        return b;
 
                 *(z++) = (uint8_t) a << 4 | (uint8_t) b;
         }
diff --git a/src/basic/log.c b/src/basic/log.c
index 557212c022..1362b1c086 100644
--- a/src/basic/log.c
+++ b/src/basic/log.c
@@ -981,24 +981,30 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
         if (streq(key, "debug") && !value)
                 log_set_max_level(LOG_DEBUG);
 
-        else if (streq(key, "systemd.log_target") && value) {
+        else if (proc_cmdline_key_streq(key, "systemd.log_target")) {
+
+                if (proc_cmdline_value_missing(key, value))
+                        return 0;
 
                 if (log_set_target_from_string(value) < 0)
                         log_warning("Failed to parse log target '%s'. Ignoring.", value);
 
-        } else if (streq(key, "systemd.log_level") && value) {
+        } else if (proc_cmdline_key_streq(key, "systemd.log_level")) {
+
+                if (proc_cmdline_value_missing(key, value))
+                        return 0;
 
                 if (log_set_max_level_from_string(value) < 0)
                         log_warning("Failed to parse log level '%s'. Ignoring.", value);
 
-        } else if (streq(key, "systemd.log_color") && value) {
+        } else if (proc_cmdline_key_streq(key, "systemd.log_color")) {
 
-                if (log_show_color_from_string(value) < 0)
+                if (log_show_color_from_string(value ?: "1") < 0)
                         log_warning("Failed to parse log color setting '%s'. Ignoring.", value);
 
-        } else if (streq(key, "systemd.log_location") && value) {
+        } else if (proc_cmdline_key_streq(key, "systemd.log_location")) {
 
-                if (log_show_location_from_string(value) < 0)
+                if (log_show_location_from_string(value ?: "1") < 0)
                         log_warning("Failed to parse log location setting '%s'. Ignoring.", value);
         }
 
@@ -1009,10 +1015,9 @@ void log_parse_environment(void) {
         const char *e;
 
         if (get_ctty_devnr(0, NULL) < 0)
-                /* Only try to read the command line in daemons.
-                   We assume that anything that has a controlling
-                   tty is user stuff. */
-                (void) parse_proc_cmdline(parse_proc_cmdline_item, NULL, true);
+                /* Only try to read the command line in daemons.  We assume that anything that has a controlling tty is
+                   user stuff. */
+                (void) proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_STRIP_RD_PREFIX);
 
         e = secure_getenv("SYSTEMD_LOG_TARGET");
         if (e && log_set_target_from_string(e) < 0)
diff --git a/src/basic/mount-util.c b/src/basic/mount-util.c
index 840e94a553..f0bc9cac18 100644
--- a/src/basic/mount-util.c
+++ b/src/basic/mount-util.c
@@ -673,6 +673,9 @@ int mount_verbose(
         else if ((flags & MS_BIND) && !type)
                 log_debug("Bind-mounting %s on %s (%s \"%s\")...",
                           what, where, strnull(fl), strempty(options));
+        else if (flags & MS_MOVE)
+                log_debug("Moving mount %s → %s (%s \"%s\")...",
+                          what, where, strnull(fl), strempty(options));
         else
                 log_debug("Mounting %s on %s (%s \"%s\")...",
                           strna(type), where, strnull(fl), strempty(options));
diff --git a/src/basic/proc-cmdline.c b/src/basic/proc-cmdline.c
index 8297a222b7..6ecb6c3f0d 100644
--- a/src/basic/proc-cmdline.c
+++ b/src/basic/proc-cmdline.c
@@ -34,17 +34,30 @@
 #include "virt.h"
 
 int proc_cmdline(char **ret) {
+        const char *e;
         assert(ret);
 
+        /* For testing purposes it is sometimes useful to be able to override what we consider /proc/cmdline to be */
+        e = secure_getenv("SYSTEMD_PROC_CMDLINE");
+        if (e) {
+                char *m;
+
+                m = strdup(e);
+                if (!m)
+                        return -ENOMEM;
+
+                *ret = m;
+                return 0;
+        }
+
         if (detect_container() > 0)
                 return get_process_cmdline(1, 0, false, ret);
         else
                 return read_one_line_file("/proc/cmdline", ret);
 }
 
-int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, void *data),
-                       void *data,
-                       bool strip_prefix) {
+int proc_cmdline_parse(proc_cmdline_parse_t parse_item, void *data, unsigned flags) {
+
         _cleanup_free_ char *line = NULL;
         const char *p;
         int r;
@@ -58,7 +71,7 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, voi
         p = line;
         for (;;) {
                 _cleanup_free_ char *word = NULL;
-                char *value = NULL, *unprefixed;
+                char *value, *key, *q;
 
                 r = extract_first_word(&p, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
                 if (r < 0)
@@ -66,17 +79,23 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, voi
                 if (r == 0)
                         break;
 
-                /* Filter out arguments that are intended only for the
-                 * initrd */
-                unprefixed = startswith(word, "rd.");
-                if (unprefixed && !in_initrd())
-                        continue;
+                key = word;
+
+                /* Filter out arguments that are intended only for the initrd */
+                q = startswith(word, "rd.");
+                if (q) {
+                        if (!in_initrd())
+                                continue;
+
+                        if (flags & PROC_CMDLINE_STRIP_RD_PREFIX)
+                                key = q;
+                }
 
-                value = strchr(word, '=');
+                value = strchr(key, '=');
                 if (value)
                         *(value++) = 0;
 
-                r = parse_item(strip_prefix && unprefixed ? unprefixed : word, value, data);
+                r = parse_item(key, value, data);
                 if (r < 0)
                         return r;
         }
@@ -84,13 +103,64 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, voi
         return 0;
 }
 
-int get_proc_cmdline_key(const char *key, char **value) {
+static bool relaxed_equal_char(char a, char b) {
+
+        return a == b ||
+                (a == '_' && b == '-') ||
+                (a == '-' && b == '_');
+}
+
+char *proc_cmdline_key_startswith(const char *s, const char *prefix) {
+
+        assert(s);
+        assert(prefix);
+
+        /* Much like startswith(), but considers "-" and "_" the same */
+
+        for (; *prefix != 0; s++, prefix++)
+                if (!relaxed_equal_char(*s, *prefix))
+                        return NULL;
+
+        return (char*) s;
+}
+
+bool proc_cmdline_key_streq(const char *x, const char *y) {
+        assert(x);
+        assert(y);
+
+        /* Much like streq(), but considers "-" and "_" the same */
+
+        for (; *x != 0 || *y != 0; x++, y++)
+                if (!relaxed_equal_char(*x, *y))
+                        return false;
+
+        return true;
+}
+
+int proc_cmdline_get_key(const char *key, unsigned flags, char **value) {
         _cleanup_free_ char *line = NULL, *ret = NULL;
         bool found = false;
         const char *p;
         int r;
 
-        assert(key);
+        /* Looks for a specific key on the kernel command line. Supports two modes:
+         *
+         * a) The "value" parameter is used. In this case a parameter beginning with the "key" string followed by "="
+         *    is searched, and the value following this is returned in "value".
+         *
+         * b) as above, but the PROC_CMDLINE_VALUE_OPTIONAL flag is set. In this case if the the key is found as a
+         *    separate word (i.e. not followed by "=" but instead by whitespace or the end of the command line), then
+         *    this is also accepted, and "value" is returned as NULL.
+         *
+         * c) The "value" parameter is NULL. In this case a search for the exact "key" parameter is performed.
+         *
+         * In all three cases, > 0 is returned if the key is found, 0 if not.*/
+
+        if (isempty(key))
+                return -EINVAL;
+
+        if ((flags & PROC_CMDLINE_VALUE_OPTIONAL) && !value)
+                return -EINVAL;
 
         r = proc_cmdline(&line);
         if (r < 0)
@@ -107,21 +177,26 @@ int get_proc_cmdline_key(const char *key, char **value) {
                 if (r == 0)
                         break;
 
-                /* Filter out arguments that are intended only for the
-                 * initrd */
+                /* Automatically filter out arguments that are intended only for the initrd, if we are not in the
+                 * initrd. */
                 if (!in_initrd() && startswith(word, "rd."))
                         continue;
 
                 if (value) {
-                        e = startswith(word, key);
+                        e = proc_cmdline_key_startswith(word, key);
                         if (!e)
                                 continue;
 
-                        r = free_and_strdup(&ret, e);
-                        if (r < 0)
-                                return r;
+                        if (*e == '=') {
+                                r = free_and_strdup(&ret, e+1);
+                                if (r < 0)
+                                        return r;
+
+                                found = true;
+
+                        } else if (*e == 0 && (flags & PROC_CMDLINE_VALUE_OPTIONAL))
+                                found = true;
 
-                        found = true;
                 } else {
                         if (streq(word, key))
                                 found = true;
@@ -134,20 +209,42 @@ int get_proc_cmdline_key(const char *key, char **value) {
         }
 
         return found;
+}
+
+int proc_cmdline_get_bool(const char *key, bool *ret) {
+        _cleanup_free_ char *v = NULL;
+        int r;
+
+        assert(ret);
+
+        r = proc_cmdline_get_key(key, PROC_CMDLINE_VALUE_OPTIONAL, &v);
+        if (r < 0)
+                return r;
+        if (r == 0) {
+                *ret = false;
+                return 0;
+        }
+
+        if (v) { /* parameter passed */
+                r = parse_boolean(v);
+                if (r < 0)
+                        return r;
+                *ret = r;
+        } else /* no parameter passed */
+                *ret = true;
 
+        return 1;
 }
 
 int shall_restore_state(void) {
-        _cleanup_free_ char *value = NULL;
+        bool ret;
         int r;
 
-        r = get_proc_cmdline_key("systemd.restore_state=", &value);
+        r = proc_cmdline_get_bool("systemd.restore_state", &ret);
         if (r < 0)
                 return r;
-        if (r == 0)
-                return true;
 
-        return parse_boolean(value);
+        return r > 0 ? ret : true;
 }
 
 static const char * const rlmap[] = {
diff --git a/src/basic/proc-cmdline.h b/src/basic/proc-cmdline.h
index 6d6ee95c11..ebfed355e9 100644
--- a/src/basic/proc-cmdline.h
+++ b/src/basic/proc-cmdline.h
@@ -19,11 +19,36 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include <stdbool.h>
+
+#include "log.h"
+
+enum {
+        PROC_CMDLINE_STRIP_RD_PREFIX = 1,
+        PROC_CMDLINE_VALUE_OPTIONAL = 2,
+};
+
+typedef int (*proc_cmdline_parse_t)(const char *key, const char *value, void *data);
+
 int proc_cmdline(char **ret);
-int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value, void *data),
-                       void *data,
-                       bool strip_prefix);
-int get_proc_cmdline_key(const char *parameter, char **value);
+
+int proc_cmdline_parse(const proc_cmdline_parse_t parse, void *userdata, unsigned flags);
+
+int proc_cmdline_get_key(const char *parameter, unsigned flags, char **value);
+int proc_cmdline_get_bool(const char *key, bool *ret);
+
+char *proc_cmdline_key_startswith(const char *s, const char *prefix);
+bool proc_cmdline_key_streq(const char *x, const char *y);
 
 int shall_restore_state(void);
 const char* runlevel_to_target(const char *rl);
+
+/* A little helper call, to be used in proc_cmdline_parse_t callbacks */
+static inline bool proc_cmdline_value_missing(const char *key, const char *value) {
+        if (!value) {
+                log_warning("Missing argument for %s= kernel command line switch, ignoring.", key);
+                return true;
+        }
+
+        return false;
+}
diff --git a/src/basic/stat-util.c b/src/basic/stat-util.c
index 309e84b93d..7e1914aa14 100644
--- a/src/basic/stat-util.c
+++ b/src/basic/stat-util.c
@@ -28,6 +28,7 @@
 
 #include "dirent-util.h"
 #include "fd-util.h"
+#include "fs-util.h"
 #include "macro.h"
 #include "missing.h"
 #include "stat-util.h"
@@ -143,22 +144,29 @@ int path_is_read_only_fs(const char *path) {
 }
 
 int path_is_os_tree(const char *path) {
-        char *p;
         int r;
 
         assert(path);
 
-        /* We use /usr/lib/os-release as flag file if something is an OS */
-        p = strjoina(path, "/usr/lib/os-release");
-        r = access(p, F_OK);
-        if (r >= 0)
-                return 1;
+        /* Does the path exist at all? If not, generate an error immediately. This is useful so that a missing root dir
+         * always results in -ENOENT, and we can properly distuingish the case where the whole root doesn't exist from
+         * the case where just the os-release file is missing. */
+        if (laccess(path, F_OK) < 0)
+                return -errno;
 
-        /* Also check for the old location in /etc, just in case. */
-        p = strjoina(path, "/etc/os-release");
-        r = access(p, F_OK);
+        /* We use /usr/lib/os-release as flag file if something is an OS */
+        r = chase_symlinks("/usr/lib/os-release", path, CHASE_PREFIX_ROOT, NULL);
+        if (r == -ENOENT) {
+
+                /* Also check for the old location in /etc, just in case. */
+                r = chase_symlinks("/etc/os-release", path, CHASE_PREFIX_ROOT, NULL);
+                if (r == -ENOENT)
+                        return 0; /* We got nothing */
+        }
+        if (r < 0)
+                return r;
 
-        return r >= 0;
+        return 1;
 }
 
 int files_same(const char *filea, const char *fileb) {
@@ -196,7 +204,7 @@ int fd_check_fstype(int fd, statfs_f_type_t magic_value) {
 int path_check_fstype(const char *path, statfs_f_type_t magic_value) {
         _cleanup_close_ int fd = -1;
 
-        fd = open(path, O_RDONLY);
+        fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_PATH);
         if (fd < 0)
                 return -errno;
 
@@ -216,3 +224,13 @@ int fd_is_temporary_fs(int fd) {
 
         return is_temporary_fs(&s);
 }
+
+int path_is_temporary_fs(const char *path) {
+        _cleanup_close_ int fd = -1;
+
+        fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_PATH);
+        if (fd < 0)
+                return -errno;
+
+        return fd_is_temporary_fs(fd);
+}
diff --git a/src/basic/stat-util.h b/src/basic/stat-util.h
index 56d28f791e..5d571efe18 100644
--- a/src/basic/stat-util.h
+++ b/src/basic/stat-util.h
@@ -61,6 +61,7 @@ int path_check_fstype(const char *path, statfs_f_type_t magic_value);
 
 bool is_temporary_fs(const struct statfs *s) _pure_;
 int fd_is_temporary_fs(int fd);
+int path_is_temporary_fs(const char *path);
 
 /* Because statfs.t_type can be int on some architectures, we have to cast
  * the const magic to the type, otherwise the compiler warns about