Merge pull request #19793 from keszybz/tmpfiles-autofs-and-globs

tmpfiles: better handling of autofs and globs

TODO

@@ -711,9 +711,6 @@ Features:
 * add proper dbus APIs for the various sd_notify() commands, such as MAINPID=1
   and so on, which would mean we could report errors and such.
 
-* teach tmpfiles.d q/Q logic something sensible in the context of XFS/ext4
-  project quota
-
 * introduce DefaultSlice= or so in system.conf that allows changing where we
   place our units by default, i.e. change system.slice to something
   else. Similar, ManagerSlice= should exist so that PID1's own scope unit could
@@ -1335,6 +1332,8 @@ Features:
     should not follow symlinks. None of the other adjustment or creation
     calls follow symlinks.
   - add --test mode
+  - teach tmpfiles.d q/Q logic something sensible in the context of XFS/ext4
+    project quota
 
 * make sure systemd-ask-password-wall does not shutdown systemd-ask-password-console too early
 

src/basic/glob-util.c

@@ -71,3 +71,22 @@ int glob_extend(char ***strv, const char *path, int flags) {
 
         return strv_extend_strv(strv, g.gl_pathv, false);
 }
+
+int glob_non_glob_prefix(const char *path, char **ret) {
+        /* Return the path of the path that has no glob characters. */
+
+        size_t n = strcspn(path, GLOB_CHARS);
+
+        if (path[n] != '\0')
+                while (n > 0 && path[n-1] != '/')
+                        n--;
+
+        if (n == 0)
+                return -ENOENT;
+
+        char *ans = strndup(path, n);
+        if (!ans)
+                return -ENOMEM;
+        *ret = ans;
+        return 0;
+}

src/basic/glob-util.h

@@ -13,6 +13,8 @@ int safe_glob(const char *path, int flags, glob_t *pglob);
 int glob_exists(const char *path);
 int glob_extend(char ***strv, const char *path, int flags);
 
+int glob_non_glob_prefix(const char *path, char **ret);
+
 #define _cleanup_globfree_ _cleanup_(globfree)
 
 _pure_ static inline bool string_is_glob(const char *p) {

src/test/test-glob-util.c

@@ -13,6 +13,8 @@
 #include "tmpfile-util.h"
 
 static void test_glob_exists(void) {
+        log_info("/* %s */", __func__);
+
         char name[] = "/tmp/test-glob_exists.XXXXXX";
         int fd = -1;
         int r;
@@ -48,6 +50,8 @@ static void test_glob_no_dot(void) {
 
         int r;
 
+        log_info("/* %s */", __func__);
+
         assert_se(mkdtemp(template));
 
         fn = strjoina(template, "/*");
@@ -68,6 +72,8 @@ static void test_safe_glob(void) {
         _cleanup_globfree_ glob_t g = {};
         int r;
 
+        log_info("/* %s */", __func__);
+
         assert_se(mkdtemp(template));
 
         fn = strjoina(template, "/*");
@@ -93,10 +99,32 @@ static void test_safe_glob(void) {
         (void) rm_rf(template, REMOVE_ROOT|REMOVE_PHYSICAL);
 }
 
+static void test_glob_non_glob_prefix_one(const char *path, const char *expected) {
+        _cleanup_free_ char *t;
+
+        assert_se(glob_non_glob_prefix(path, &t) == 0);
+        assert_se(streq(t, expected));
+}
+
+static void test_glob_non_glob(void) {
+        log_info("/* %s */", __func__);
+
+        test_glob_non_glob_prefix_one("/tmp/.X11-*", "/tmp/");
+        test_glob_non_glob_prefix_one("/tmp/*", "/tmp/");
+        test_glob_non_glob_prefix_one("/tmp*", "/");
+        test_glob_non_glob_prefix_one("/tmp/*/whatever", "/tmp/");
+        test_glob_non_glob_prefix_one("/tmp/*/whatever?", "/tmp/");
+        test_glob_non_glob_prefix_one("/?", "/");
+
+        char *x;
+        assert_se(glob_non_glob_prefix("?", &x) == -ENOENT);
+}
+
 int main(void) {
         test_glob_exists();
         test_glob_no_dot();
         test_safe_glob();
+        test_glob_non_glob();
 
         return 0;
 }

src/tmpfiles/tmpfiles.c

@@ -2344,6 +2344,8 @@ static int clean_item(Item *i) {
 
 static int process_item(Item *i, OperationMask operation) {
         OperationMask todo;
+        _cleanup_free_ char *_path = NULL;
+        const char *path;
         int r, q, p;
 
         assert(i);
@@ -2354,9 +2356,21 @@ static int process_item(Item *i, OperationMask operation) {
 
         i->done |= operation;
 
-        r = chase_symlinks(i->path, arg_root, CHASE_NO_AUTOFS|CHASE_WARN, NULL, NULL);
+        path = i->path;
+        if (string_is_glob(path)) {
+                /* We can't easily check whether a glob matches any autofs path, so let's do the check only
+                 * for the non-glob part. */
+
+                r = glob_non_glob_prefix(path, &_path);
+                if (r < 0 && r != -ENOENT)
+                        return log_debug_errno(r, "Failed to deglob path: %m");
+                if (r >= 0)
+                        path = _path;
+        }
+
+        r = chase_symlinks(path, arg_root, CHASE_NO_AUTOFS|CHASE_NONEXISTENT|CHASE_WARN, NULL, NULL);
         if (r == -EREMOTE) {
-                log_notice_errno(r, "Skipping %s", i->path);
+                log_notice_errno(r, "Skipping %s", i->path); /* We log the configured path, to not confuse the user. */
                 return 0;
         }
         if (r < 0)