Merge pull request #5203 from poettering/dotdot

trivial unification of checking for "." and ".." when iterating through directories...

TODO

@@ -24,6 +24,13 @@ Janitorial Clean-ups:
 
 Features:
 
+* journald: when we recv a log datagram via the native or syslog transports,
+  search for the PID in the active stream connections, and let's make sure to
+  always process the datagrams before the streams. Then, cache client metadata
+  per stream in the stream object. This way we can somewhat fix the race with
+  quickly exiting processes which log as long as they had their own stream
+  connection...
+
 * Maybe add a small tool invoked early at boot, that adds in or resizes
   partitions automatically, to be used when the media used is actually larger
   than the image written onto it is.

src/basic/cgroup-util.c

@@ -182,8 +182,7 @@ int cg_read_subgroup(DIR *d, char **fn) {
                 if (de->d_type != DT_DIR)
                         continue;
 
-                if (streq(de->d_name, ".") ||
-                    streq(de->d_name, ".."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 b = strdup(de->d_name);

src/basic/copy.c

@@ -331,7 +331,7 @@ static int fd_copy_directory(
                 struct stat buf;
                 int q;
 
-                if (STR_IN_SET(de->d_name, ".", ".."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 if (fstatat(dirfd(d), de->d_name, &buf, AT_SYMLINK_NOFOLLOW) < 0) {

src/basic/hexdecoct.c

@@ -72,10 +72,10 @@ int unhexchar(char c) {
 }
 
 char *hexmem(const void *p, size_t l) {
-        char *r, *z;
         const uint8_t *x;
+        char *r, *z;
 
-        z = r = malloc(l * 2 + 1);
+        z = r = new(char, l * 2 + 1);
         if (!r)
                 return NULL;
 

src/basic/path-util.c

@@ -699,10 +699,7 @@ bool filename_is_valid(const char *p) {
         if (isempty(p))
                 return false;
 
-        if (streq(p, "."))
-                return false;
-
-        if (streq(p, ".."))
+        if (dot_or_dot_dot(p))
                 return false;
 
         e = strchrnul(p, '/');
@@ -720,14 +717,17 @@ bool path_is_safe(const char *p) {
         if (isempty(p))
                 return false;
 
-        if (streq(p, "..") || startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
+        if (dot_or_dot_dot(p))
+                return false;
+
+        if (startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
                 return false;
 
         if (strlen(p)+1 > PATH_MAX)
                 return false;
 
         /* The following two checks are not really dangerous, but hey, they still are confusing */
-        if (streq(p, ".") || startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
+        if (startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
                 return false;
 
         if (strstr(p, "//"))
@@ -892,3 +892,16 @@ int systemd_installation_has_version(const char *root, unsigned minimal_version)
 
         return false;
 }
+
+bool dot_or_dot_dot(const char *path) {
+        if (!path)
+                return false;
+        if (path[0] != '.')
+                return false;
+        if (path[1] == 0)
+                return true;
+        if (path[1] != '.')
+                return false;
+
+        return path[2] == 0;
+}

src/basic/path-util.h

@@ -141,3 +141,5 @@ bool is_device_path(const char *path);
 bool is_deviceallow_pattern(const char *path);
 
 int systemd_installation_has_version(const char *root, unsigned minimal_version);
+
+bool dot_or_dot_dot(const char *path);

src/basic/rm-rf.c

@@ -83,7 +83,7 @@ int rm_rf_children(int fd, RemoveFlags flags, struct stat *root_dev) {
                 bool is_dir;
                 struct stat st;
 
-                if (streq(de->d_name, ".") || streq(de->d_name, ".."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 if (de->d_type == DT_UNKNOWN ||

src/basic/socket-util.c

@@ -877,7 +877,7 @@ bool ifname_valid(const char *p) {
         if (strlen(p) >= IFNAMSIZ)
                 return false;
 
-        if (STR_IN_SET(p, ".", ".."))
+        if (dot_or_dot_dot(p))
                 return false;
 
         while (*p) {

src/gpt-auto-generator/gpt-auto-generator.c

@@ -658,7 +658,7 @@ static int get_block_device_harder(const char *path, dev_t *dev) {
 
         FOREACH_DIRENT_ALL(de, d, return -errno) {
 
-                if (STR_IN_SET(de->d_name, ".", ".."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 if (!IN_SET(de->d_type, DT_LNK, DT_UNKNOWN))

src/nspawn/nspawn-patch-uid.c

@@ -375,7 +375,7 @@ static int recurse_fd(int fd, bool donate_fd, const struct stat *st, uid_t shift
                 FOREACH_DIRENT_ALL(de, d, r = -errno; goto finish) {
                         struct stat fst;
 
-                        if (STR_IN_SET(de->d_name, ".", ".."))
+                        if (dot_or_dot_dot(de->d_name))
                                 continue;
 
                         if (fstatat(dirfd(d), de->d_name, &fst, AT_SYMLINK_NOFOLLOW) < 0) {

src/resolve/resolved-manager.c

@@ -1349,7 +1349,7 @@ void manager_cleanup_saved_user(Manager *m) {
                 if (!IN_SET(de->d_type, DT_UNKNOWN, DT_REG))
                         continue;
 
-                if (STR_IN_SET(de->d_name, ".", ".."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 r = parse_ifindex(de->d_name, &ifindex);

src/shared/clean-ipc.c

@@ -225,7 +225,7 @@ static int clean_posix_shm_internal(DIR *dir, uid_t uid, gid_t gid) {
         FOREACH_DIRENT_ALL(de, dir, goto fail) {
                 struct stat st;
 
-                if (STR_IN_SET(de->d_name, "..", "."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 if (fstatat(dirfd(dir), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {
@@ -310,7 +310,7 @@ static int clean_posix_mq(uid_t uid, gid_t gid) {
                 struct stat st;
                 char fn[1+strlen(de->d_name)+1];
 
-                if (STR_IN_SET(de->d_name, "..", "."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 if (fstatat(dirfd(dir), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {

src/test/test-fs-util.c

@@ -305,12 +305,23 @@ static void test_var_tmp(void) {
         }
 }
 
+static void test_dot_or_dot_dot(void) {
+        assert_se(!dot_or_dot_dot(NULL));
+        assert_se(!dot_or_dot_dot(""));
+        assert_se(!dot_or_dot_dot("xxx"));
+        assert_se(dot_or_dot_dot("."));
+        assert_se(dot_or_dot_dot(".."));
+        assert_se(!dot_or_dot_dot(".foo"));
+        assert_se(!dot_or_dot_dot("..foo"));
+}
+
 int main(int argc, char *argv[]) {
         test_unlink_noerrno();
         test_readlink_and_make_absolute();
         test_get_files_in_directory();
         test_var_tmp();
         test_chase_symlinks();
+        test_dot_or_dot_dot();
 
         return 0;
 }

src/tmpfiles/tmpfiles.c

@@ -385,7 +385,7 @@ static int dir_cleanup(
                 usec_t age;
                 _cleanup_free_ char *sub_path = NULL;
 
-                if (STR_IN_SET(dent->d_name, ".", ".."))
+                if (dot_or_dot_dot(dent->d_name))
                         continue;
 
                 if (fstatat(dirfd(d), dent->d_name, &s, AT_SYMLINK_NOFOLLOW) < 0) {
@@ -1070,9 +1070,7 @@ static int item_do_children(Item *i, const char *path, action_t action) {
                 _cleanup_free_ char *p = NULL;
                 int q;
 
-                errno = 0;
-
-                if (STR_IN_SET(de->d_name, ".", ".."))
+                if (dot_or_dot_dot(de->d_name))
                         continue;
 
                 p = strjoin(path, "/", de->d_name);