Use udev_encode_string in fstab_node_to_udev_node

Resolves a longstanding bug which caused this function to wrongly
handle (escape) valid utf8 characters.

2 files changed, 45 insertions, 11 deletions

diff --git a/src/shared/util.c b/src/shared/util.c
index f6f3b18bfc..2b76a5c885 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -73,6 +73,7 @@
 #include "hashmap.h"
 #include "env-util.h"
 #include "fileio.h"
+#include "utf8.h"
 
 int saved_argc = 0;
 char **saved_argv = NULL;
@@ -3495,26 +3496,23 @@ int signal_from_string_try_harder(const char *s) {
 }
 
 static char *tag_to_udev_node(const char *tagvalue, const char *by) {
-        char *dn, *t, *u;
-        int r;
-
-        /* FIXME: to follow udev's logic 100% we need to leave valid
-         * UTF8 chars unescaped */
+        _cleanup_free_ char *t = NULL, *u = NULL;
+        char *dn;
+        size_t enc_len;
 
         u = unquote(tagvalue, "\"\'");
         if (u == NULL)
                 return NULL;
 
-        t = xescape(u, "/ ");
-        free(u);
-
+        enc_len = strlen(u) * 4;
+        t = new(char, enc_len);
         if (t == NULL)
                 return NULL;
 
-        r = asprintf(&dn, "/dev/disk/by-%s/%s", by, t);
-        free(t);
+        if (udev_encode_string(u, t, enc_len) < 0)
+                return NULL;
 
-        if (r < 0)
+        if (asprintf(&dn, "/dev/disk/by-%s/%s", by, t) < 0)
                 return NULL;
 
         return dn;
diff --git a/src/test/test-util.c b/src/test/test-util.c
index dd7768d36c..ad13d53de3 100644
--- a/src/test/test-util.c
+++ b/src/test/test-util.c
@@ -547,6 +547,41 @@ static void test_split_pair(void) {
         assert_se(streq(b, "="));
 }
 
+static void test_fstab_node_to_udev_node(void) {
+        char *n;
+
+        n = fstab_node_to_udev_node("LABEL=applé/jack");
+        puts(n);
+        assert_se(streq(n, "/dev/disk/by-label/applé\\x2fjack"));
+        free(n);
+
+        n = fstab_node_to_udev_node("PARTLABEL=pinkié pie");
+        puts(n);
+        assert_se(streq(n, "/dev/disk/by-partlabel/pinkié\\x20pie"));
+        free(n);
+
+        n = fstab_node_to_udev_node("UUID=037b9d94-148e-4ee4-8d38-67bfe15bb535");
+        puts(n);
+        assert_se(streq(n, "/dev/disk/by-uuid/037b9d94-148e-4ee4-8d38-67bfe15bb535"));
+        free(n);
+
+        n = fstab_node_to_udev_node("PARTUUID=037b9d94-148e-4ee4-8d38-67bfe15bb535");
+        puts(n);
+        assert_se(streq(n, "/dev/disk/by-partuuid/037b9d94-148e-4ee4-8d38-67bfe15bb535"));
+        free(n);
+
+
+        n = fstab_node_to_udev_node("PONIES=awesome");
+        puts(n);
+        assert_se(streq(n, "PONIES=awesome"));
+        free(n);
+
+        n = fstab_node_to_udev_node("/dev/xda1");
+        puts(n);
+        assert_se(streq(n, "/dev/xda1"));
+        free(n);
+}
+
 int main(int argc, char *argv[]) {
         test_streq_ptr();
         test_first_word();
@@ -582,6 +617,7 @@ int main(int argc, char *argv[]) {
         test_strrep();
         test_parse_user_at_host();
         test_split_pair();
+        test_fstab_node_to_udev_node();
 
         return 0;
 }